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-rw-r--r--profiles/use.desc401
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diff --git a/profiles/use.desc b/profiles/use.desc
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+# Copyright 1999-2018 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+# Keep them sorted
+
+3dfx - Enable support for Voodoo chipsets, also called as 3DFX and TDFX
+X - Add support for X11
+Xaw3d - Add support for the 3d athena widget set
+a52 - Enable support for decoding ATSC A/52 streams used in DVD
+aac - Enable support for MPEG-4 AAC Audio
+aalib - Add support for media-libs/aalib (ASCII-Graphics Library)
+accessibility - Add support for accessibility (eg 'at-spi' library)
+acl - Add support for Access Control Lists
+acpi - Add support for Advanced Configuration and Power Interface
+adns - Add support for asynchronous DNS resolution
+afs - Add OpenAFS support (distributed file system)
+aim - Enable AIM IM protocol support
+alsa - Add support for media-libs/alsa-lib (Advanced Linux Sound Architecture)
+altivec - Add support for optimizations for G4 and G5/ppc970 processors
+ao - Use libao audio output library for sound playback
+apache2 - Add Apache2 support
+apm - Add APM (Advanced Power Management) support
+aqua - Include support for the Mac OS X Aqua (Carbon/Cocoa) GUI
+atm - Enable Asynchronous Transfer Mode protocol support
+audiofile - Add support for libaudiofile where applicable
+audit - Enable support for Linux audit subsystem using sys-process/audit
+avahi - Add avahi/Zeroconf support
+ayatana - Build in support for Ayatana notification using the libindicate or libappindicator plugin
+bash-completion - Enable bash-completion support
+bcmath - Add support for libbcmath
+berkdb - Add support for sys-libs/db (Berkeley DB for MySQL)
+bidi - Enable bidirectional language support
+big-endian - Big-endian toolchain support
+bindist - Flag to enable or disable options for prebuilt (GRP) packages (eg. due to licensing issues)
+blas - Add support for the virtual/blas numerical library
+bluetooth - Enable Bluetooth Support
+bootstrap - !!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during original system bootstrapping [make stage2]
+boundschecking - Add the bounds checking patch by Haj Ten Brugge, this will DISABLE the hardened PIE+SSP patches
+branding - Enable Gentoo specific branding
+bsf - Enable support for Apache Bean Scripting Framework (dev-java/bsf)
+build - !!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used for creating build images and the first half of bootstrapping [make stage1]
+bzip2 - Use the bzlib compression library
+cairo - Enable support for the cairo graphics library
+calendar - Add support for calendars (not using mcal!)
+canna - Add support for the Canna kana to kanji conversion engine
+caps - Use Linux capabilities library to control privilege
+cdb - Add support for the CDB database engine from the author of qmail
+cdda - Add Compact Disk Digital Audio (Standard Audio CD) support
+cddb - Access cddb servers to retrieve and submit information about compact disks
+cdinstall - Copy files from the CD rather than asking the user to copy them, mostly used with games
+cdparanoia - Enable cdparanoia (audio CD ripper) support
+cdr - Add support for CD writer hardware
+cgi - Add CGI script support
+cjk - Add support for Multi-byte character languages (Chinese, Japanese, Korean)
+clamav - Add support for Clam AntiVirus software (usually with a plugin)
+connman - Add support for net-misc/connman
+coreaudio - Build the CoreAudio driver on Mac OS X systems
+cracklib - Support for cracklib strong password checking
+crypt - Add support for encryption -- using mcrypt or gpg where applicable
+cscope - Enable cscope interface -- in vim for example
+css - Enable reading of encrypted DVDs
+ctype - Enable ctype functions
+cups - Add support for CUPS (Common Unix Printing System)
+curl - Add support for client-side URL transfer library
+custom-cflags - Build with user-specified CFLAGS (unsupported)
+cvs - Enable CVS (Concurrent Versions System) integration
+cxx - Build support for C++ (bindings, extra libraries, code generation, ...)
+dbi - Enable dev-db/libdbi (database-independent abstraction layer) support
+dbm - Add support for generic DBM databases
+dbus - Enable dbus support for anything that needs it (gpsd, gnomemeeting, etc)
+debug - Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces
+dedicated - Add support for dedicated game servers (some packages do not provide clients and servers at the same time)
+dga - Add DGA (Direct Graphic Access) support for X
+directfb - Add support for DirectFB layer (library for FB devices)
+djvu - Support DjVu, a PDF-like document format esp. suited for scanned documents
+doc - Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally
+dri - Enable direct rendering: used for accelerated 3D and some 2D, like DMA
+dts - Enable DTS Coherent Acoustics decoder support
+dv - Enable support for a codec used by many camcorders
+dvb - Add support for DVB (Digital Video Broadcasting)
+dvd - Add support for DVDs
+dvdr - Add support for DVD writer hardware (e.g. in xcdroast)
+eds - Enable support for Evolution-Data-Server (EDS)
+emacs - Add support for GNU Emacs
+emboss - Add support for the European Molecular Biology Open Software Suite
+encode - Add support for encoding of audio or video files
+enscript - Add enscript support to colourize code stored in the repository
+evo - Add support for mail-client/evolution
+examples - Install examples, usually source code
+exif - Add support for reading EXIF headers from JPEG and TIFF images
+expat - Enable the use of dev-libs/expat for XML parsing
+fam - Enable FAM (File Alteration Monitor) support
+fastcgi - Add support for the FastCGI interface
+fbcon - Add framebuffer support for the console, via the kernel
+ffmpeg - Enable ffmpeg/libav-based audio/video codec support
+fftw - Use FFTW library for computing Fourier transforms
+filecaps - Use Linux file capabilities to control privilege rather than set*id (this is orthogonal to USE=caps which uses capabilities at runtime e.g. libcap)
+firebird - Add support for the Firebird relational database
+flac - Add support for FLAC: Free Lossless Audio Codec
+flatfile - Add dbm support for flat files
+fltk - Add support for the Fast Light Toolkit gui interface
+fontconfig - Support for configuring and customizing font access via media-libs/fontconfig
+foomaticdb - Add support for the foomatic printing driver database
+fortran - Add support for fortran
+freetds - Add support for the TDS protocol to connect to MSSQL/Sybase databases
+freewnn - Add support for FreeWnn kana to kanji conversion engine
+ftp - Add FTP (File Transfer Protocol) support
+gcj - Enable building with gcj (The GNU Compiler for the Javatm Programming Language)
+gd - Add support for media-libs/gd (to generate graphics on the fly)
+gdbm - Add support for sys-libs/gdbm (GNU database libraries)
+geoip - Add geoip support for country and city lookup based on IPs
+geolocation - Enable physical position determination
+ggi - Add support for media-libs/libggi (non-X video api/drivers)
+gif - Add GIF image support
+gimp - Build a plugin for the GIMP
+git - Enable git (version control system) support
+glut - Build an OpenGL plugin using the GLUT library
+gmp - Add support for dev-libs/gmp (GNU MP library)
+gnome - Add GNOME support
+gnome-keyring - Enable support for storing passwords via gnome-keyring
+gnuplot - Enable support for gnuplot (data and function plotting)
+gnutls - Prefer net-libs/gnutls as SSL/TLS provider (ineffective with USE=-ssl)
+gphoto2 - Add digital camera support
+gpm - Add support for sys-libs/gpm (Console-based mouse driver)
+gps - Add support for Global Positioning System
+graphicsmagick - Build and link against GraphicsMagick instead of ImageMagick (might require USE=imagemagick if optional)
+graphviz - Add support for the Graphviz library
+gsl - Use the GNU scientific library for calculations
+gsm - Add support for the gsm lossy speech compression codec
+gstreamer - Add support for media-libs/gstreamer (Streaming media)
+gtk - Add support for x11-libs/gtk+ (The GIMP Toolkit)
+guile - Add support for the guile Scheme interpreter
+gzip - Compress files with Lempel-Ziv coding (LZ77)
+handbook - Enable handbooks generation for packages by KDE
+hardened - Activate default security enhancements for toolchain (gcc, glibc, binutils)
+hddtemp - Enable monitoring of hdd temperature (app-admin/hddtemp)
+hdf5 - Add support for the Hierarchical Data Format v5
+headers-only - Install only C headers instead of whole package. Mainly used by sys-devel/crossdev for toolchain bootstrap.
+hscolour - Include coloured haskell sources to generated documentation (dev-haskell/hscolour)
+ibm - Add support for IBM ppc64 specific systems
+iconv - Enable support for the iconv character set conversion library
+icq - Enable ICQ IM protocol support
+icu - Enable ICU (Internationalization Components for Unicode) support, using dev-libs/icu
+idn - Enable support for Internationalized Domain Names
+ieee1394 - Enable FireWire/iLink IEEE1394 support (dv, camera, ...)
+imagemagick - Enable optional support for the ImageMagick or GraphicsMagick image converter
+imap - Add support for IMAP (Internet Mail Application Protocol)
+imlib - Add support for imlib, an image loading and rendering library
+infiniband - Enable Infiniband RDMA transport support
+inifile - Add dbm support for .ini files
+inotify - Enable inotify filesystem monitoring support
+introspection - Add support for GObject based introspection
+iodbc - Add support for iODBC library
+ios - Enable support for Apple's iDevice with iOS operating system (iPad, iPhone, iPod, etc)
+ipod - Enable support for iPod device access
+ipv6 - Add support for IP version 6
+iwmmxt - Add support for optimizations for ARM iwMMXt instructions
+jack - Add support for the JACK Audio Connection Kit
+java - Add support for Java
+javascript - Enable javascript support
+jbig - Enable jbig-kit support for tiff, Hylafax, ImageMagick, etc
+jingle - Enable voice calls for jabber
+jit - Enable just-in-time compilation for improved performance. May prevent use of some PaX memory protection features in Gentoo Hardened.
+joystick - Add support for joysticks in all packages
+jpeg - Add JPEG image support
+jpeg2k - Support for JPEG 2000, a wavelet-based image compression format
+kde - Add support for KDE (K Desktop Environment)
+kerberos - Add kerberos support
+ladspa - Enable the ability to support ladspa plugins
+lame - Prefer using LAME libraries for MP3 encoding support
+lapack - Add support for the virtual/lapack numerical library
+lash - Add LASH Audio Session Handler support
+latex - Add support for LaTeX (typesetting package)
+lcms - Add lcms support (color management engine)
+ldap - Add LDAP support (Lightweight Directory Access Protocol)
+libass - SRT/SSA/ASS (SubRip / SubStation Alpha) subtitle support
+libav - Prefer libav over ffmpeg whenever both are supported
+libcaca - Add support for colored ASCII-art graphics
+libedit - Use the libedit library (replacement for readline)
+libffi - Enable support for Foreign Function Interface library
+libnotify - Enable desktop notification support
+libressl - Use dev-libs/libressl instead of dev-libs/openssl as SSL/TLS provider (ineffective with USE=-ssl), packages should not depend on this USE flag
+libsamplerate - Build with support for converting sample rates using libsamplerate
+libwww - Add libwww support (General purpose WEB API)
+lirc - Add support for lirc (Linux's Infra-Red Remote Control)
+livecd - !!internal use only!! DO NOT SET THIS FLAG YOURSELF!, used during livecd building
+lm_sensors - Add linux lm_sensors (hardware sensors) support
+lua - Enable Lua scripting support
+lzma - Support for LZMA (de)compression algorithm
+lzo - Enable support for lzo compression
+m17n-lib - Enable m17n-lib support
+mad - Add support for mad (high-quality mp3 decoder library and cli frontend)
+maildir - Add support for maildir (~/.maildir) style mail spools
+matroska - Add support for the matroska container format (extensions .mkv, .mka and .mks)
+mbox - Add support for mbox (/var/spool/mail) style mail spools
+memcached - Add support for memcached
+memlimit - Add memory usage limiting in supporting programs
+mhash - Add support for the mhash library
+migemo - Enable migemo support for Japanese
+mikmod - Add libmikmod support to allow playing of SoundTracker-style music files
+milter - Add sendmail mail filter (milter) support
+mime - Add MIME support
+minimal - Install a very minimal build (disables, for example, plugins, fonts, most drivers, non-critical features)
+mmap - Add mmap (memory map) support
+mms - Support for Microsoft Media Server (MMS) streams
+mng - Add support for libmng (MNG images)
+modplug - Add libmodplug support for playing SoundTracker-style music files
+modules - Build the kernel modules
+mono - Build Mono bindings to support dotnet type stuff
+motif - Add support for the Motif toolkit
+mozilla - Add support for the Mozilla web-browser
+mp3 - Add support for reading mp3 files
+mp4 - Support for MP4 container format
+mpeg - Add libmpeg3 support to various packages
+mpi - Add MPI (Message Passing Interface) layer to the apps that support it
+mplayer - Enable mplayer support for playback or encoding
+msn - Enable MSN Messenger IM protocol support
+mssql - Add support for Microsoft SQL Server database
+mtp - Enable support for Media Transfer Protocol
+mule - Add multi-language support to XEmacs
+multilib - On 64bit systems, if you want to be able to compile 32bit and 64bit binaries
+musepack - Enable support for the musepack audio codec
+musicbrainz - Lookup audio metadata using MusicBrainz community service (musicbrainz.org)
+mysql - Add mySQL Database support
+mysqli - Add support for the improved mySQL libraries
+nas - Add support for network audio sound
+ncurses - Add ncurses support (console display library)
+neXt - Enable neXt toolkit
+neon - Enable optimization support for ARM NEON processors
+netboot - Enable network booting
+netcdf - Enable NetCDF data format support
+networkmanager - Enable net-misc/networkmanager support
+nis - Support for NIS/YP services
+nls - Add Native Language Support (using gettext - GNU locale utilities)
+nntp - Add support for newsgroups (Network News Transfer Protocol)
+nocd - Install all files required to run the application without a CD mounted
+nptl - Enable support for Native POSIX Threads Library, the new threading module (requires linux-2.6 or better usually)
+nsplugin - Build plugin for browsers supporting the Netscape plugin architecture (that is almost any modern browser)
+ocaml - Add support/bindings for the Ocaml language
+ocamlopt - Enable ocamlopt support (ocaml native code compiler) -- Produces faster programs (Warning: you have to disable/enable it at a global scale)
+oci8 - Add Oracle 8 Database Support
+oci8-instant-client - Use dev-db/oracle-instantclient-basic as Oracle provider instead of requiring a full Oracle server install
+odbc - Add ODBC Support (Open DataBase Connectivity)
+offensive - Enable potentially offensive items in packages
+ofx - Enable support for importing (and exporting) OFX (Open Financial eXchange) data files
+ogg - Add support for the Ogg container format (commonly used by Vorbis, Theora and flac)
+openal - Add support for the Open Audio Library
+openexr - Support for the OpenEXR graphics file format
+opengl - Add support for OpenGL (3D graphics)
+openmp - Build support for the OpenMP (support parallel computing), requires >=sys-devel/gcc-4.2 built with USE="openmp"
+oracle - Enable Oracle Database support
+orc - Use dev-lang/orc for just-in-time optimization of array operations
+osc - Enable support for Open Sound Control
+oscar - Enable Oscar (AIM/ICQ) IM protocol support
+oss - Add support for OSS (Open Sound System)
+pam - Add support for PAM (Pluggable Authentication Modules) - DANGEROUS to arbitrarily flip
+pch - Enable precompiled header support for faster compilation at the expense of disk space and memory (>=sys-devel/gcc-3.4 only)
+pcmcia - Add support for PCMCIA slots/devices found on laptop computers
+pcntl - Add support for process creation functions
+pcre - Add support for Perl Compatible Regular Expressions
+pda - Add support for portable devices
+pdf - Add general support for PDF (Portable Document Format), this replaces the pdflib and cpdflib flags
+perl - Add optional support/bindings for the Perl language
+php - Include support for the PHP language
+pie - Build programs as Position Independent Executables (a security hardening technique)
+plasma - Build optional KDE plasma addons
+plotutils - Add support for plotutils (library for 2-D vector graphics)
+png - Add support for libpng (PNG images)
+policykit - Enable PolicyKit authentication support
+portaudio - Add support for the crossplatform portaudio audio API
+posix - Add support for POSIX-compatible functions
+postgres - Add support for the postgresql database
+postscript - Enable support for the PostScript language (often with ghostscript-gpl or libspectre)
+ppds - Add support for automatically generated ppd (printing driver) files
+prefix - Defines if a Gentoo Prefix offset installation is used
+prelude - Add support/bindings for the Prelude Intrusion Detection System
+profile - Add support for software performance analysis (will likely vary from ebuild to ebuild)
+pulseaudio - Add support for PulseAudio sound server
+python - Add optional support/bindings for the Python language
+qdbm - Add support for the qdbm (Quick Database Manager) library
+qmail-spp - Add support for qmail SMTP plugins
+qt4 - Add support for the Qt GUI/Application Toolkit version 4.x
+qt5 - Add support for the Qt 5 application and UI framework
+quicktime - Add support for OpenQuickTime
+radius - Add support for RADIUS authentication
+raw - Add support for raw image formats
+rdp - Enables RDP/Remote Desktop support
+readline - Enable support for libreadline, a GNU line-editing library that almost everyone wants
+recode - Enable support for the GNU recode library
+rss - Enable support for RSS feeds
+ruby - Add support/bindings for the Ruby language
+samba - Add support for SAMBA (Windows File and Printer sharing)
+sasl - Add support for the Simple Authentication and Security Layer
+savedconfig - Use this to restore your config from /etc/portage/savedconfig ${CATEGORY}/${PN}. Make sure your USE flags allow for appropriate dependencies
+scanner - Add support for scanner hardware (e.g. build the sane frontend in kdegraphics)
+sctp - Support for Stream Control Transmission Protocol
+sdl - Add support for Simple Direct Layer (media library)
+seamonkey - Add support for the Seamonkey web-browser
+seccomp - Enable seccomp (secure computing mode) to perform system call filtering at runtime to increase security of programs
+selinux - !!internal use only!! Security Enhanced Linux support, this must be set by the selinux profile or breakage will occur
+semantic-desktop - Cross-KDE support for semantic search and information retrieval
+session - Add persistent session support
+sharedmem - Add support for shared memory use
+shorten - Add support for the shorten audio compressor
+simplexml - Support for SimpleXML
+skey - Enable S/Key (Single use password) authentication support
+slang - Add support for the slang text display library (it's like ncurses, but different)
+slp - Add Service Locator Protocol support
+smartcard - Enable smartcard support
+smp - Enable support for multiprocessors or multicore systems
+sndfile - Add support for libsndfile
+snmp - Add support for the Simple Network Management Protocol if available
+soap - Add support for SOAP (Simple Object Access Protocol)
+sockets - Add support for tcp/ip sockets
+socks5 - Add support for the socks5 proxy
+sound - Enable sound support
+source - Zip the sources and install them
+sox - Add support for Sound eXchange (SoX)
+speex - Add support for the speex audio codec (used for speech)
+spell - Add dictionary support
+sqlite - Add support for sqlite - embedded sql database
+ssl - Add support for SSL/TLS connections (Secure Socket Layer / Transport Layer Security)
+startup-notification - Enable application startup event feedback mechanism
+static - !!do not set this during bootstrap!! Causes binaries to be statically linked instead of dynamically
+static-libs - Build static versions of dynamic libraries as well
+subversion - Enable subversion (version control system) support
+suid - Enable setuid root program, with potential security risks
+svg - Add support for SVG (Scalable Vector Graphics)
+svga - Add support for SVGAlib (graphics library)
+sybase - Add support for the Sybase SQL Database Server
+sybase-ct - Add support for Sybase-CT
+symlink - Force kernel ebuilds to automatically update the /usr/src/linux symlink
+syslog - Enable support for syslog
+systemd - Enable use of systemd-specific libraries and features like socket activation or session tracking
+sysvipc - Support for System V-compatible inter-process communication
+szip - Use the szip compression library
+taglib - Enable tagging support with taglib
+tcl - Add support the Tcl language
+tcmalloc - Use the dev-util/google-perftools libraries to replace the malloc() implementation with a possibly faster one
+tcpd - Add support for TCP wrappers
+test - Workaround to pull in packages needed to run with FEATURES=test. Portage-2.1.2 handles this internally, so don't set it in make.conf/package.use anymore
+theora - Add support for the Theora Video Compression Codec
+threads - Add threads support for various packages. Usually pthreads
+tidy - Add support for HTML Tidy
+tiff - Add support for the TIFF image format
+timidity - Build with Timidity++ (MIDI sequencer) support
+tk - Add support for Tk GUI toolkit
+tokenizer - Add support for the PHP file parser
+truetype - Add support for FreeType and/or FreeType2 fonts
+uclibc - Enable uclibc specific patches and build or link uclibc
+udev - Enable virtual/udev integration (device discovery, power and storage device support, etc)
+udisks - Enable storage management support (automounting, volume monitoring, etc)
+unicode - Add support for Unicode
+unwind - Add support for call stack unwinding and function name resolution
+upnp - Enable UPnP port mapping support
+upnp-av - Enable UPnP audio/video streaming support
+upower - Enable power management support
+usb - Add USB support to applications that have optional USB support (e.g. cups)
+v4l - Enable support for video4linux (using linux-headers or userspace libv4l libraries)
+vaapi - Enable Video Acceleration API for hardware decoding
+vala - Enable bindings for dev-lang/vala
+vanilla - Do not add extra patches which change default behaviour; DO NOT USE THIS ON A GLOBAL SCALE as the severity of the meaning changes drastically
+vcd - Video CD support
+vdpau - Enable the Video Decode and Presentation API for Unix acceleration interface
+vhosts - Add support for installing web-based applications into a virtual-hosting environment
+videos - Install optional video files (used in some games)
+vim-syntax - Pulls in related vim syntax scripts
+vnc - Enable VNC (remote desktop viewer) support
+vorbis - Add support for the OggVorbis audio codec
+wavpack - Add support for wavpack audio compression tools
+wayland - Enable dev-libs/wayland backend
+wddx - Add support for Web Distributed Data eXchange
+webkit - Add support for the WebKit HTML rendering/layout engine
+webp - Add support for the WebP image format
+wifi - Enable wireless network functions
+wmf - Add support for the Windows Metafile vector image format
+wxwidgets - Add support for wxWidgets/wxGTK GUI toolkit
+x264 - Enable h264 encoding using x264
+xattr - Add support for extended attributes (filesystem-stored metadata)
+xcb - Support the X C-language Binding, a replacement for Xlib
+xcomposite - Enable support for the Xorg composite extension
+xemacs - Add support for XEmacs
+xface - Add xface support used to allow a small image of xface format to be included in an email via the header 'X-Face'
+xft - Build with support for XFT font renderer (x11-libs/libXft)
+xine - Add support for the XINE movie libraries
+xinerama - Add support for querying multi-monitor screen geometry through the Xinerama API
+xinetd - Add support for the xinetd super-server
+xml - Add support for XML files
+xmlrpc - Support for xml-rpc library
+xmp - Enable support for Extensible Metadata Platform (Adobe XMP)
+xmpp - Enable support for Extensible Messaging and Presence Protocol (XMPP) formerly known as Jabber
+xosd - Sends display using the X On Screen Display library
+xpm - Add support for XPM graphics format
+xscreensaver - Add support for XScreenSaver extension
+xv - Add in optional support for the Xvideo extension (an X API for video playback)
+xvid - Add support for xvid.org's open-source mpeg-4 codec
+yahoo - Enable Yahoo Messenger IM protocol support
+yaz - Add in optional support for the Z39.50 Protocol for Information Retrieval (YAZ)
+zeroconf - Support for DNS Service Discovery (DNS-SD)
+zlib - Add support for zlib (de)compression
+zsh-completion - Enable zsh completion support
diff --git a/profiles/use.local.desc b/profiles/use.local.desc
new file mode 100644
index 00000000..c5f3c311
--- /dev/null
+++ b/profiles/use.local.desc
@@ -0,0 +1,9023 @@
+# This file is deprecated as per GLEP 56 in favor of metadata.xml. Please add
+# your descriptions to your package's metadata.xml ONLY.
+# * generated automatically using egencache *
+
+app-accessibility/brltty:api - build brltty's application program interface
+app-accessibility/brltty:beeper - support the console tone generator
+app-accessibility/brltty:contracted-braille - support in-line contracted braille
+app-accessibility/brltty:fm - support for the sound card synthesizer
+app-accessibility/brltty:midi - support the musical instrument digital interface
+app-accessibility/brltty:pcm - support for sound card digital audio
+app-accessibility/brltty:speech - speech support
+app-accessibility/eflite:16k_voice - Use a higher-quality voice.
+app-accessibility/emacspeak:espeak - Adds support for the espeak tts engine
+app-accessibility/festival-it:mbrola - Adds support for mbrola voices
+app-accessibility/freetts:jsapi - build Java Speech API (JSAPI)
+app-accessibility/freetts:mbrola - Adds support for mbrola voices
+app-accessibility/orca:braille - Enable braille support
+app-accessibility/simon:opencv - Use media-libs/opencv
+app-accessibility/simon:pim - Enable support for KDE PIM resources integration
+app-accessibility/simon:sphinx - Build sphinx backend (pulls app-accessibility/julius if disabled
+app-accessibility/speech-dispatcher:espeak - Adds support for espeak speech engine
+app-accessibility/speech-dispatcher:flite - Adds support for flite speech engine
+app-accessibility/speechd-el:brltty - brltty support
+app-admin/bcfg2:cheetah - Include dev-python/cheetah support
+app-admin/bcfg2:genshi - Include dev-python/genshi support
+app-admin/bcfg2:server - Installs scripts to be used on the server-side of this app
+app-admin/calamares:pythonqt - Enable PythonQt-based module interface
+app-admin/clsync:cgroups - Use cgroups to limit /dev access.
+app-admin/clsync:cluster - Enable clustering support (allows master-master clsync on multiple hosts). Not fully implemented yet.
+app-admin/clsync:control-socket - Enable AF_UNIX control socket support.
+app-admin/clsync:extra-debug - Enable extra debugging. This will hurt performance badly. Be ready for tons of output.
+app-admin/clsync:extra-hardened - Enable extra security checks. This will hurt performance.
+app-admin/clsync:gio - Enable GIO for FS monitoring (glib based alternative to inotify interface, not recommended; if both are compiled, may be selected at runtime).
+app-admin/clsync:highload-locks - Allows to use spinlocks for short delays instead of mutexes, but only on SMP systems.
+app-admin/clsync:namespaces - Enable namespaces isolation.
+app-admin/collectd:contrib - Install user-contributed files in the doc directory
+app-admin/collectd:filecaps - When set collectd daemon will have set required capabilities to run most plugins even if run as unprivileged user
+app-admin/collectd:java - Must be set (workaround for java-pkg-opt-2 eclass limitation) when you want java or genericjmx plugin
+app-admin/collectd:udev - Enable optional udev usage in disk plugin; Required for smart plugin
+app-admin/collectd:xfs - Enable optional capability to filter on XFS file system in df plugin; Requires XFS headers from sys-fs/xfsprogs
+app-admin/conky:apcupsd - Enable support for sys-power/apcupsd
+app-admin/conky:audacious - Enable monitoring of music played by media-sound/audacious
+app-admin/conky:cmus - Enable monitoring of music played by media-sound/cmus
+app-admin/conky:eve - Enable support for the eve-online skill monitor
+app-admin/conky:ical - Enable support for events from iCalendar (RFC 5545) files using dev-libs/libical
+app-admin/conky:iostats - Enable support for per-task I/O statistics
+app-admin/conky:irc - Enable support for displaying everything from an irc channel using net-libs/libircclient
+app-admin/conky:lua-cairo - Enable if you want Lua Cairo bindings
+app-admin/conky:lua-imlib - Enable if you want Lua Imlib2 bindings
+app-admin/conky:lua-rsvg - Enable if you want Lua RSVG bindings
+app-admin/conky:math - Enable support for glibc's libm math library
+app-admin/conky:moc - Enable monitoring of music played by media-sound/moc
+app-admin/conky:mpd - Enable monitoring of music controlled by media-sound/mpd
+app-admin/conky:nano-syntax - Enable syntax highlighting for app-editors/nano
+app-admin/conky:nvidia - Enable reading of nvidia card temperature sensors via media-video/nvidia-settings
+app-admin/conky:portmon - Enable support for tcp (ip4) port monitoring
+app-admin/conky:thinkpad - Enable support for IBM/Lenovo notebooks
+app-admin/conky:weather-metar - Enable support for metar weather service
+app-admin/conky:weather-xoap - Enable support for metar and xoap weather service
+app-admin/conky:webserver - Enable support to act as a webserver serving conkys output using net-libs/libmicrohttpd
+app-admin/conky:xmms2 - Enable monitoring of music played by media-sound/xmms2
+app-admin/diamond:mongo - Enable MongoDB support
+app-admin/diamond:redis - Enable Redis support
+app-admin/diradm:automount - Support for automount data in LDAP
+app-admin/diradm:irixpasswd - Support for storing separate IRIX passwords
+app-admin/elektra:augeas - Enable plugin for reading and writing configuration files with help from Augeas
+app-admin/elektra:ini - Enable new, advanced ini support
+app-admin/elektra:simpleini - Enable simpleini support
+app-admin/elektra:uname - Enable uname information for the key database
+app-admin/elektra:yajl - Enable yajl support
+app-admin/gkrellm:X - Build both the X11 gui (gkrellm) and the server (gkrellmd). Disabling this flag builds the server only
+app-admin/gkrellm:gnutls - Enable SSL support for mail checking with net-libs/gnutls (overrides 'ssl' USE flag)
+app-admin/gkrellm:hddtemp - Enable monitoring harddrive temperatures via app-admin/hddtemp
+app-admin/gkrellm:lm_sensors - Enable monitoring sensors via sys-apps/lm_sensors
+app-admin/gkrellm:ntlm - Enable NTLM authentication for mail checking with net-libs/libntlm
+app-admin/gkrellm:ssl - Enable SSL support for mail checking with dev-libs/openssl
+app-admin/glance:swift - Adds swift storage support
+app-admin/gtkdiskfree:gtk2 - Support GTK+ 2.x instead of GTK+ 3.x
+app-admin/hddtemp:network-cron - Monthly cronjob to update hddtemp.db.
+app-admin/keepass:aot - Generate native code at build time, rather than runtime.
+app-admin/keepassxc:autotype - Add support to autotype the passwords into other applications
+app-admin/keepassxc:browser - Enables browser plugin support
+app-admin/keepassxc:http - Add http support
+app-admin/keepassxc:network - Enable network support
+app-admin/keepassxc:yubikey - Enable database unlocking via YubiKey.
+app-admin/lastpass-cli:X - Use x11-misc/xclip or x11-misc/xsel to copy passwords to the clipboard.
+app-admin/lastpass-cli:pinentry - Use app-crypt/pinentry to prompt for passwords.
+app-admin/logrotate:acl - Installs acl support
+app-admin/logrotate:cron - Installs cron file
+app-admin/logrotate:selinux - Installs Security Enhanced Linux support
+app-admin/matter:entropy - Add Entropy support
+app-admin/mcollective:client - Install client utilities
+app-admin/mms-agent:monitoring - Install the monitoring agent
+app-admin/openrc-settingsd:systemd - Use the versions of dbus and polkit files provided by sys-apps/systemd
+app-admin/packagekit-base:command-not-found - Enable packagekit support on shell "command not found"
+app-admin/packagekit-base:cron - Install cron script for auto-update
+app-admin/packagekit-base:elogind - Enable elogind support to get user session
+app-admin/packagekit-base:entropy - Enable Entropy backend
+app-admin/pass:X - Use x11-misc/xclip to copy passwords to the clipboard.
+app-admin/pass:dmenu - Add support for x11-misc/dmenu with the 'passmenu' program.
+app-admin/pass:fish-completion - Enable fish completion support.
+app-admin/pass:git - Use dev-vcs/git for password revisions.
+app-admin/pass:importers - Allow importing passwords from other password managers using various contributed scripts.
+app-admin/passwordsafe:minimal - Avoid collision with app-misc/pwsafe
+app-admin/passwordsafe:qr - Enable QR code password display
+app-admin/passwordsafe:xml - Enable XML import support
+app-admin/passwordsafe:yubikey - Enable support for Yubikey
+app-admin/prelude-manager:dbx - Enables Prelude Manager storing Prelude alerts into database through dev-libs/libpreludedb .
+app-admin/prelude-manager:tcpwrapper - Enables Prelude Manager using tcp wrapper. It requires sys-apps/tcp-wrappers .
+app-admin/puppet:augeas - Enable augeas support
+app-admin/puppet:diff - Enable diff support
+app-admin/puppet:experimental - Add patches for things in testing
+app-admin/puppet:rrdtool - Enable rrdtool support
+app-admin/puppet:shadow - Enable shadow support
+app-admin/puppet-agent:experimental - Add patches for things in testing
+app-admin/puppet-agent:puppetdb - Adds puppetdb support
+app-admin/puppetserver:puppetdb - Adds support for connecting to puppetdb
+app-admin/pwgen:livecd - Install init script for root password scrambling on boot
+app-admin/rsyslog:curl - Enable http_request() function in RainerScript (requires net-misc/curl)
+app-admin/rsyslog:dbi - Build the general database output module (requires dev-db/libdbi)
+app-admin/rsyslog:elasticsearch - Build the Elasticsearch output module (requires net-misc/curl)
+app-admin/rsyslog:gcrypt - Add support for encrypted log files using dev-libs/libgcrypt
+app-admin/rsyslog:grok - Build the grok modify module (requires dev-libs/grok)
+app-admin/rsyslog:jemalloc - Use dev-libs/jemalloc for allocations.
+app-admin/rsyslog:kafka - Build the Apache Kafka input/output module (requires dev-libs/librdkafka)
+app-admin/rsyslog:kerberos - Build the GSSAPI input and output module (requires virtual/krb5)
+app-admin/rsyslog:libressl - Use dev-libs/libressl for building the rfc5424hmac modify module (requires rfc5424hmac USE flag)
+app-admin/rsyslog:mdblookup - Build the MaxMind DB lookup message modify plugin using dev-libs/libmaxminddb
+app-admin/rsyslog:mongodb - Build the MongoDB output module (requires dev-libs/libmongo-client)
+app-admin/rsyslog:mysql - Build the MySQL database output module (requires virtual/mysql)
+app-admin/rsyslog:normalize - Build the normalize modify module (requires dev-libs/libee and dev-libs/liblognorm)
+app-admin/rsyslog:omhttpfs - Build the httpfs output module (requires net-misc/curl)
+app-admin/rsyslog:omudpspoof - Build the udpspoof output module (requires net-libs/libnet)
+app-admin/rsyslog:postgres - Build the PostgreSQL database output module (requires dev-db/postgresql)
+app-admin/rsyslog:rabbitmq - Build the RabbitMQ output module (requires net-libs/rabbitmq-c)
+app-admin/rsyslog:redis - Build the Redis output module using (requires dev-libs/hiredis)
+app-admin/rsyslog:relp - Build the Reliable Event Logging Protocol (RELP) output module (requires dev-libs/librelp)
+app-admin/rsyslog:rfc3195 - Build the rfc3195 input module (requires dev-libs/liblogging)
+app-admin/rsyslog:rfc5424hmac - Build the rfc5424hmac modify module (requires dev-libs/openssl or dev-libs/libressl)
+app-admin/rsyslog:snmp - Build the snmp modify and output module (requires net-analyzer/net-snmp)
+app-admin/rsyslog:ssl - Add support for encrypted client/server communication (requires net-libs/gnutls)
+app-admin/rsyslog:systemd - Build the journal input and output module (requires sys-apps/systemd)
+app-admin/rsyslog:usertools - Installs the user tools (rsgtutil, rscryutil...) corresponding to the set USE flags
+app-admin/rsyslog:uuid - Include UUIDs in messages (requires sys-apps/util-linux)
+app-admin/rsyslog:zeromq - Build the ZeroMQ input and output modules (requires net-libs/czmq)
+app-admin/sagan:libdnet - Add support for dev-libs/libdnet
+app-admin/sagan:lognorm - Add support for log/rules normalizations via dev-libs/liblognorm
+app-admin/sagan:pcap - Add support for network packet capture via net-libs/libpcap
+app-admin/sagan:smtp - Build witch SMTP (E-Mail) support
+app-admin/sagan:snort - Add support to interact with Snort IDE using net-analyzer/snortsam'
+app-admin/sagan-rules:lognorm - Install normalize rules support with dev-libs/liblognorm
+app-admin/salt:cherrypy - Enable support for using cherrypy.
+app-admin/salt:gnupg - Enable support for gnupg via python-gnupg.
+app-admin/salt:keyring - Enable support for keyrings via python-keyring.
+app-admin/salt:libcloud - Enable salt-cloud support via libcloud.
+app-admin/salt:libvirt - Support managing virtual machines with app-emulation/libvirt.
+app-admin/salt:mako - Add support for using the mako template engine for parsing salt states.
+app-admin/salt:mongodb - Support returning data to a mongodb server.
+app-admin/salt:neutron - Support the OpenStack neutron network service.
+app-admin/salt:nova - Enable support for the OpenStack Nova API
+app-admin/salt:openssl - Add support for using TLS via OpenSSL.
+app-admin/salt:portage - Add support for package state enforcement using sys-apps/portage
+app-admin/salt:raet - Add support for the new RAET transport.
+app-admin/salt:redis - Support returning data to a redis database.
+app-admin/salt:timelib - Use timelib to parse english textual date descriptions.
+app-admin/salt:zeromq - Add support for the zeromq transport.
+app-admin/sshguard:ipfilter - Enable ipfilter firewall support (only for *bsd)
+app-admin/sudo:gcrypt - Use SHA2 from dev-libs/libgcrypt instead of sudo's internal SHA2
+app-admin/sudo:offensive - Let sudo print insults when the user types the wrong password
+app-admin/sudo:openssl - Use SHA2 from dev-libs/openssl instead of sudo's internal SHA2
+app-admin/sudo:sendmail - Allow sudo to send emails with sendmail
+app-admin/sysklogd:logrotate - use app-admin/logrotate for rotating logs rather than custom cron scripts
+app-admin/syslog-ng:amqp - Enable support for AMQP destinations
+app-admin/syslog-ng:http - Enable support for HTTP destinations
+app-admin/syslog-ng:json - Enable support for JSON template formatting via dev-libs/json-c
+app-admin/syslog-ng:mongodb - Enable support for mongodb destinations
+app-admin/syslog-ng:pacct - Enable support for reading Process Accounting files (EXPERIMENTAL, Linux only)
+app-admin/syslog-ng:redis - Enable support for Redis destinations
+app-admin/syslog-ng:smtp - Enable support for SMTP destinations
+app-admin/syslog-ng:spoof-source - Enable support for spoofed source addresses
+app-admin/sysstat:isag - Install isag, the Interactive System Activity Graph tool
+app-admin/systemrescuecd-x86:isohybrid - Pass downloaded images through isohybrid in order to make it possible to copy them directly to USB media and boot (requires sys-boot/syslinux at build time).
+app-admin/testdisk:ewf - Include ewf library
+app-admin/testdisk:ntfs - Include the ability to read NTFS filesystems
+app-admin/testdisk:reiserfs - Include reiserfs reading ability
+app-admin/tripwire:ssl - Adds support for Secure Socket Layer connections
+app-admin/tripwire:static - Builds the package statically
+app-admin/tripwire:tools - Installs app-admin/mktwpol, providing scripts for the installation/setup of tripwire, including generating the tripwire policy file and maintenance of the tripwire database
+app-admin/ulogd:json - Build JSON output plugin to save packets in JSON file format
+app-admin/ulogd:nfacct - Build NFACCT input plugin to support traffic accounting via nfnetlink_acct
+app-admin/ulogd:nfct - Build NFCT input plugin to support stateful flow-based logging via nfnetlink_conntrack
+app-admin/ulogd:nflog - Build NFLOG input plugin to support stateless packet-based logging via nfnetlink_log
+app-admin/ulogd:pcap - Build PCAP output plugin to save packets in libpcap file format
+app-admin/ulogd:ulog - Build ULOG input plugin to support deprecated packet-based logging via ULOG target
+app-admin/webalizer:xtended - Include the 404 extension
+app-admin/webapp-config:portage - Propagete python_targets dependencies to sys-apps/portage
+app-admin/yaala:storable - Support for persistence of Perl data structures.
+app-antivirus/clamav:clamdtop - A Top like tool which shows what clamd is currently scanning amongst other things
+app-antivirus/clamav:metadata-analysis-api - Enables collection of file property metadata using ClamAV API for analysis by ClamAV bytecode programs.
+app-arch/cabextract:extras - Install experimental extra tools: wince_info and wince_rename for examining and processing Windows CE installation cabinet header files; cabinfo for examining the structure of a cab file.
+app-arch/cfv:bittorrent - Enable support for checking .torrent files
+app-arch/deltarpm:system-zlib - Use system sys-libs/zlib. Do not enable features of rsync friendly.
+app-arch/dpkg:update-alternatives - Install update-alternatives
+app-arch/dump:ermt - encrypted rmt support
+app-arch/dump:uuid - Enable UUID support
+app-arch/engrampa:caja - Enable engrampa to integrate with mate-base/caja by providing entries in its context menu
+app-arch/engrampa:gtk3 - Build with GTK+3 instead of GTK+2
+app-arch/engrampa:magic - Enable filetype auto-detection via sys-apps/file
+app-arch/engrampa:packagekit - Enable support for installing via app-admin/packagekit based on archive type
+app-arch/file-roller:nautilus - Build contextual menu extension for gnome-base/nautilus.
+app-arch/file-roller:packagekit - Enable support for the distro-neutral package manager GUI app-admin/packagekit
+app-arch/gzip:pic - disable optimized assembly code that is not PIC friendly
+app-arch/innoextract:c++0x - Compile innoextract using the C++11 standard
+app-arch/innoextract:debug - Enable debug logging and the --debug command-line option
+app-arch/innoextract:lzma - Enable support for extracting lzma-compressed installers using app-arch/xz-utils
+app-arch/libarchive:bzip2 - Allow accessing bzip2-compressed archives through libbz2 (which comes with app-arch/bzip2). This only affects libarchive's native support: bsdtar will keep using bunzip2 as a filter if that's not built-in.
+app-arch/libarchive:e2fsprogs - Use file flags from sys-fs/e2fsprogs headers instead of virtual/os-headers headers
+app-arch/libarchive:lz4 - Enable support for LZ4 compression using app-arch/lz4
+app-arch/libarchive:nettle - Use dev-libs/nettle as crypto backend
+app-arch/libarchive:zlib - Allow accessing gzip-compressed archives through sys-libs/zlib. This only affects libarchive's native support: bsdtar will keep using gunzip as a filter if that's not built-in. It's also needed for supporting extraction of ZIP files.
+app-arch/lz4:valgrind - Enable usage of dev-util/valgrind in tests
+app-arch/p7zip:rar - Enable support for non-free rar decoder
+app-arch/pbzip2:symlink - Install symlinks which override app-arch/bzip2 implementation
+app-arch/pigz:symlink - Install symlinks which override app-arch/gzip implementation
+app-arch/rar:all_sfx - Install all SFX (Self-Extracting) files rather than just the native format (allows creation of Windows EXEs on Linux ELF systems)
+app-arch/tar:minimal - just install `tar`
+app-arch/unzip:natspec - Use dev-libs/libnatspec to correctly decode non-ascii file names archived in Windows.
+app-arch/wimlib:fuse - Use fuse libraries
+app-arch/wimlib:iso - Install app-cdr/cdrtools in order to prepare iso images
+app-arch/wimlib:ntfs - Use libntfs-3g library from sys-fs/ntfs3g
+app-arch/wimlib:openssl - Use the SHA-1 message digest from libcrypto instead of compilling another implementation
+app-arch/wimlib:yasm - Use yasm assembler instead of nasm
+app-arch/xz-utils:extra-filters - Build additional filters that are not used in any of the default xz presets. This includes delta and BCJ coders, additional match finders and SHA256 checks.
+app-arch/zip:natspec - Use dev-libs/libnatspec to correctly decode non-ascii file names archived in Windows.
+app-backup/amanda:ndmp - Support for the NDMP protocol
+app-backup/amanda:s3 - Support for backing up to the Amazon S3 system
+app-backup/amanda:xfs - Support for backing up raw XFS filesystems using xfsdump
+app-backup/backup-manager:s3 - Support for backing up to the Amazon S3 system
+app-backup/bacula:bacula-clientonly - Disable DB support, and just build a client
+app-backup/bacula:bacula-nodir - Disable building of director
+app-backup/bacula:bacula-nosd - Disable building of storage daemon
+app-backup/bacula:logwatch - Install support files for logwatch
+app-backup/bareos:cephfs - Enable cephfs storage backend
+app-backup/bareos:clientonly - Only install file-daemon (client)
+app-backup/bareos:director - Install director
+app-backup/bareos:fastlz - Enable support vor lz4, lz4hc and lzfast using dev-libs/bareos-fastlzlib
+app-backup/bareos:glusterfs - Enable glusterfs storage backend
+app-backup/bareos:gnutls - When ssl is enabled, use GnuTLS instead of OpenSSL
+app-backup/bareos:jansson - JSON API support using JANSSON for director
+app-backup/bareos:lmdb - enable build of LMDB support for faster accurate backup
+app-backup/bareos:logwatch - Install support files for logwatch
+app-backup/bareos:ndmp - Enable support for NDMP (Network Data Management Protocol)
+app-backup/bareos:rados - Enable rados storage backend
+app-backup/bareos:rados-striper - Enable use of rados-striper
+app-backup/bareos:scsi-crypto - Enable low level SCSI crypto support
+app-backup/bareos:sql-pooling - Enable SQL pooling support
+app-backup/bareos:storage-daemon - Install storage daemon (bareos-sd)
+app-backup/btrbk:pv - Use sys-apps/pv to enable progress bar functionality
+app-backup/bup:web - Support browsing backups via a web interface
+app-backup/dar:dar32 - Enables --enable-mode=32 option, which replace infinite by 32 bit integers
+app-backup/dar:dar64 - Enables --enable-mode=64 option, which replace infinite by 64 bit integers
+app-backup/dar:gcrypt - Enables strong encryption support
+app-backup/dar:gpg - Enables usage of asymetric crypto algorithms
+app-backup/deja-dup:nautilus - Build gnome-base/nautilus extension
+app-backup/duplicity:s3 - Support for backing up to the Amazon S3 system
+app-backup/fsarchiver:lz4 - Enable lz4 compression support
+app-backup/fsarchiver:zstd - Enable zstd compression support
+app-backup/holland-backup-mysql-meta:lvm - Install Holland LVM Plugin
+app-backup/holland-backup-mysql-meta:mysqldump - Install Holland mysqldump Plugin
+app-backup/holland-backup-mysql-meta:mysqlhotcopy - Install Holland mysqlhotcopy Plugin
+app-backup/rear:udev - Have ReaR start backup when attaching your USB drive.
+app-backup/snapper:btrfs - Include Btrfs support sys-fs/btrfs-progs
+app-backup/snapper:ext4 - Include Ext4 support sys-fs/e2fsprogs
+app-backup/snapper:lvm - Enable LVM thinprovisioned snapshots support sys-fs/lvm2
+app-backup/snapper:xattr - Add support for getting and setting POSIX extended attributes, through sys-apps/attr.
+app-backup/tsm:tsm_cit - IBM Tivoli Common Inventory Technology
+app-backup/tsm:tsm_hw - Difference snapshot support for NetApp and N-Series file servers
+app-backup/zbackup:tartool - Install tartool utility
+app-benchmarks/filebench:auto-completion - Enable command-line autocompletion using dev-libs/libtecla
+app-benchmarks/httperf:idleconn - Build with the idleconn program
+app-benchmarks/ramspeed:pic - Force shared libraries to be built as PIC (this is slower)
+app-benchmarks/sysbench:aio - Enable libaio support
+app-cdr/brasero:libburn - Enable dev-libs/libburn backend
+app-cdr/brasero:nautilus - Build the gnome-base/nautilus extension
+app-cdr/brasero:packagekit - Enable support for the distro-neutral package manager GUI app-admin/packagekit
+app-cdr/brasero:playlist - Enable support for playlists through dev-libs/totem-pl-parser
+app-cdr/brasero:tracker - Enable audio playlist search using the app-misc/tracker indexer
+app-cdr/cdemu:cdemu-daemon - Pull app-cdr/cdemu-daemon dependency, useful in chroot environment (bug #315491). Do not disable until you know what you are doing.
+app-cdr/cuetools:extras - Install additional script that tag files based on cue/toc file information
+app-cdr/dvdisaster:debug - Enable memory debugging.
+app-cdr/gaffitter:scripts - Install additional gaffitter scripts for external programs
+app-cdr/mirage2iso:pinentry - Support app-crypt/pinentry password input backend.
+app-crypt/aespipe:asm - Enable assembly modules
+app-crypt/aespipe:cpu_flags_x86_padlock - Use VIA padlock instructions, detected at run time, code still works on non-padlock processors
+app-crypt/ccid:kobil-midentity - Build and install Kobil_mIDentity_switch tool
+app-crypt/ccid:twinserial - Enable twinserial reader
+app-crypt/codecrypt:cryptopp - Build algorithms that need Crypto++ support dev-libs/crypto++
+app-crypt/eid-mw:dialogs - Enable "askaccess" dialog box, by using x11-libs/gtk+
+app-crypt/eid-mw:gtk - All dialogs are available, by using x11-libs/gtk+
+app-crypt/eid-mw:p11-kit - Support for app-crypt/p11-kit.
+app-crypt/eid-mw:xpi - Build and install an extension for Mozilla browsers.
+app-crypt/ekeyd:minimal - Only install the ekey-egd-linux service rather than the full ekeyd package.
+app-crypt/ekeyd:munin - Install a plugin for net-analyzer/munin to graph statistical data from ekeyd.
+app-crypt/ekeyd:usb - Build the libusb-based userland daemon for accessing the EntropyKey (alternative to the CDC USB driver). It is suggested to use this option by default, as the CDC driver in the kernel often seems to be fragile (or the gadget implementation on the EntropyKey is too buggy), and can cause various problems.
+app-crypt/gnupg:mta - Build mta support using virtual/mta.
+app-crypt/gnupg:smartcard - Build scdaemon software. Enables usage of OpenPGP cards. For other type of smartcards, try app-crypt/gnupg-pkcs11-scd. Bring in dev-libs/libusb as a dependency; enable scdaemon.
+app-crypt/gnupg:tofu - Enable support for Trust on First use trust model; requires dev-db/sqlite.
+app-crypt/gnupg:tools - Install extra tools (including gpgsplit and gpg-zip).
+app-crypt/gnupg:usb - Build direct CCID access for scdaemon; requires dev-libs/libusb.
+app-crypt/gnupg:wks-server - Install the wks-server
+app-crypt/gnupg-pkcs11-scd:proxy - Build the gnupg-pkcs11-scd-prox
+app-crypt/gpgme:common-lisp - Install common-lisp files
+app-crypt/heimdal:hdb-ldap - Adds support for LDAP as a database backend
+app-crypt/heimdal:otp - Adds support for one-time passwords
+app-crypt/heimdal:pkinit - Adds support for PKINIT for the initial ticket
+app-crypt/hmaccalc:fips - Enable NSS FIPS mode and support only the FIPS-compliant functions
+app-crypt/johntheripper:cuda - Use nvidia cuda toolkit for speeding up cracking on capable devices
+app-crypt/johntheripper:mozilla - Support mozilla password cracking
+app-crypt/johntheripper:opencl - Enable opencl support for speeding up cracking on capable devices
+app-crypt/kbfs:git - Build the Git remote helper for storing repositories in Keybase
+app-crypt/kstart:afs - Enables afs support which means you can acquire an afs token and set PAGs. It's recommended to set this USE if you need authenticated access to an AFS cell for your daemon/app.
+app-crypt/libb2:native-cflags - Use CFLAGS as determined by configure script. These flags will enable all CPU specific features it find available, to further optimise the implementation. This discards any existing CFLAGS set in make.conf or similar.
+app-crypt/libu2f-host:systemd - Use user ACLs rather than plugdev group to give user access to the HIDRAW device.
+app-crypt/mit-krb5:doc - Creates and installs the API and implementation documentation. This is only useful if you want to develop software which depends on kerberos.
+app-crypt/mit-krb5:keyutils - Enable for the keyring ccache using keyutils.
+app-crypt/mit-krb5:openldap - Enable support for ldap as a database backend.
+app-crypt/mit-krb5:pkinit - Enable pkinit support for the initial ticket.
+app-crypt/ophcrack:tables - Require the additional tables used to carry out cracking (app-crypt/ophcrack-tables)
+app-crypt/ophcrack-tables:vistafree - Installs the free Vista ophcrack tables
+app-crypt/ophcrack-tables:xpfast - Installs the fast XP ophcrack tables
+app-crypt/ophcrack-tables:xpsmall - Installs the small free XP ophcrack tables
+app-crypt/p11-kit:asn1 - Enable ASN.1 certificate support
+app-crypt/p11-kit:trust - Build the trust policy module
+app-crypt/qca:botan - Enable botan plugin
+app-crypt/qca:gcrypt - Enable gcrypt plugin
+app-crypt/qca:gpg - Enable GnuPG plugin
+app-crypt/qca:logger - Enable logger plugin
+app-crypt/qca:nss - Enable NSS plugin
+app-crypt/qca:pkcs11 - Enable PKCS#11 plugin
+app-crypt/qca:sasl - Enable SASL plugin
+app-crypt/qca:softstore - Enable softstore plugin
+app-crypt/rhash:openssl - Add support for hashes from dev-libs/openssl
+app-crypt/seahorse:ldap - Enable seahorse to manipulate GPG keys on a LDAP server.
+app-crypt/tpm-tools:pkcs11 - Build Token data management utilities based on OpenCryptoki's (dev-libs/opencryptoki) PKCS#11 implementation.
+app-crypt/veracrypt:asm - Enable assembly for optimization
+app-crypt/zulucrypt:gnome - Enable support for the freedesktop.org Secret Service API via app-crypt/libsecret
+app-crypt/zulucrypt:kwallet - Enable encrypted storage of passwords with kde-frameworks/kwallet
+app-crypt/zulucrypt:udev - Whether udev will be consulted when deciding if a volume is system or not
+app-dicts/aspell-be:classic - Support classic spelling by default
+app-dicts/gwaei:hunspell - Enable app-text/hunspell spellchecking and morphological analysis
+app-dicts/gwaei:mecab - Enable app-text/mecab support
+app-dicts/myspell-pt:preao - Use the pre ortographic agreement version of the dictionary
+app-doc/clsync-docs:api - Install doxygen generated API docs.
+app-doc/csound-manual:html - Install HTML documentation
+app-doc/doxygen:clang - support for sys-devel/clang assisted parsing
+app-doc/doxygen:dot - allow to create dot graphs using media-gfx/graphviz
+app-doc/doxygen:doxysearch - build doxyindexer and doxysearch.cgi
+app-doc/kicad-doc:html - Generate documentation in HTML format
+app-doc/kicad-doc:pdf - Generate documentation in PDF format
+app-doc/linuxfromscratch:htmlsingle - Install all-on-one-page HTML version.
+app-doc/pms:binary - Download pre-built files instead of building from sources
+app-doc/pms:html - Generate PMS as .html as well
+app-doc/pms:twoside - Enable two-sided layout suitable for printing
+app-doc/root-docs:api - Generate html API documentation
+app-doc/root-docs:http - Build HttpServer documentation
+app-doc/root-docs:math - Provide all math related documentation
+app-doc/root-docs:metric - Default to A4 paper size and metric measurement. Letter will be used otherwise
+app-doc/tldp-howto:html - Install multi-chapter HTML docs
+app-doc/tldp-howto:htmlsingle - Install all-on-one-page HTML docs
+app-doc/tldp-howto:pdf - Install pdf docs
+app-doc/tldp-howto:text - Install plain-text docs
+app-editors/bluefish:gtk2 - Enable GTK2 instead of GTK3 even if GTK3 is available
+app-editors/bluefish:gtk3 - Enable GTK3 interface (default)
+app-editors/bluefish:gucharmap - Enable gucharmap dictionary plugin
+app-editors/bluefish:python - Enable Python integration for zen-coding plugin
+app-editors/bluefish:spell - Enable spell checking capabilities via enchant library
+app-editors/emacs:athena - Enable the MIT Athena widget set (x11-libs/libXaw)
+app-editors/emacs:dynamic-loading - Enable loading of dynamic libraries at runtime
+app-editors/emacs:games - Support shared score files for games
+app-editors/emacs:gconf - Use gnome-base/gconf to read the system font name
+app-editors/emacs:gfile - Use gfile (dev-libs/glib) for file notification
+app-editors/emacs:gsettings - Use gsettings (dev-libs/glib) to read the system font name
+app-editors/emacs:gtk3 - Prefer version 3 of the GIMP Toolkit to version 2 (x11-libs/gtk+)
+app-editors/emacs:gzip-el - Compress bundled Emacs Lisp source
+app-editors/emacs:hesiod - Enable support for net-dns/hesiod
+app-editors/emacs:imagemagick - Use media-gfx/imagemagick for image processing
+app-editors/emacs:libxml2 - Use dev-libs/libxml2 to parse XML instead of the internal Lisp implementations
+app-editors/emacs:pax_kernel - Enable building under a PaX enabled kernel
+app-editors/emacs:source - Install C source files and make them available for find-function
+app-editors/emacs:toolkit-scroll-bars - Use the selected toolkit's scrollbars in preference to Emacs' own scrollbars
+app-editors/emacs:wide-int - Prefer wide Emacs integers (typically 62-bit). This option has an effect only on architectures where "long" and "long long" types have different size.
+app-editors/emacs-vcs:athena - Enable the MIT Athena widget set (x11-libs/libXaw)
+app-editors/emacs-vcs:dynamic-loading - Enable loading of dynamic libraries at runtime
+app-editors/emacs-vcs:games - Support shared score files for games
+app-editors/emacs-vcs:gconf - Use gnome-base/gconf to read the system font name
+app-editors/emacs-vcs:gfile - Use gfile (dev-libs/glib) for file notification
+app-editors/emacs-vcs:gsettings - Use gsettings (dev-libs/glib) to read the system font name
+app-editors/emacs-vcs:gtk3 - Prefer version 3 of the GIMP Toolkit to version 2 (x11-libs/gtk+)
+app-editors/emacs-vcs:gzip-el - Compress bundled Emacs Lisp source
+app-editors/emacs-vcs:hesiod - Enable support for net-dns/hesiod
+app-editors/emacs-vcs:imagemagick - Use media-gfx/imagemagick for image processing
+app-editors/emacs-vcs:libxml2 - Use dev-libs/libxml2 to parse XML instead of the internal Lisp implementations
+app-editors/emacs-vcs:mailutils - Retrieve e-mail using net-mail/mailutils instead of the internal movemail substitute
+app-editors/emacs-vcs:pax_kernel - Enable building under a PaX enabled kernel
+app-editors/emacs-vcs:source - Install C source files and make them available for find-function
+app-editors/emacs-vcs:threads - Add elisp threading support
+app-editors/emacs-vcs:toolkit-scroll-bars - Use the selected toolkit's scrollbars in preference to Emacs' own scrollbars
+app-editors/emacs-vcs:wide-int - Prefer wide Emacs integers (typically 62-bit). This option has an effect only on architectures where "long" and "long long" types have different size.
+app-editors/emacs-vcs:xwidgets - Enable use of GTK widgets in Emacs buffers (requires GTK3)
+app-editors/fe:sendmail - Send mail after editor abend
+app-editors/gedit-plugins:charmap - Insert special characters just by clicking on them
+app-editors/gedit-plugins:git - Shows document changes related to git's HEAD
+app-editors/gedit-plugins:terminal - Embed a terminal in the bottom pane
+app-editors/gedit-plugins:zeitgeist - Build the plugin to inject events to zeitgeist
+app-editors/gvim:gtk3 - Enable GTK+3 interface
+app-editors/gvim:luajit - Use dev-lang/luajit instead of dev-lang/lua
+app-editors/gvim:netbeans - Include netbeans external editor integration support
+app-editors/gvim:racket - Enable support for Scheme using dev-scheme/racket
+app-editors/jasspa-microemacs:nanoemacs - Build NanoEmacs instead of MicroEmacs
+app-editors/joe:xterm - Enable full xterm clipboard support
+app-editors/latexila:latexmk - Install dev-tex/latexmk (used by default for the build tools)
+app-editors/latexila:rubber - Install dev-tex/rubber (can be used for the build tools)
+app-editors/leafpad:emacs - Enable Emacs key theme
+app-editors/mousepad:gtk3 - Use GTK+3 instead of GTK+2
+app-editors/nano:debug - Enable debug messages and assert warnings. Note that these will all be sent straight to stderr rather than some logging facility.
+app-editors/nano:justify - Enable justify/unjustify functions for text formatting.
+app-editors/nano:magic - Add magic file support (sys-apps/file) to automatically detect appropriate syntax highlighting
+app-editors/nano:minimal - Disable all fancy features, including ones that otherwise have a dedicated USE flag (such as spelling).
+app-editors/ne:tinfo - Link against libtinfo from sys-libs/ncurses
+app-editors/neovim:clipboard - Enable clipboard support through a provider
+app-editors/neovim:jemalloc - Use dev-libs/jemalloc for allocations
+app-editors/neovim:luajit - Use dev-lang/luajit instead of dev-lang/lua
+app-editors/neovim:nvimpager - Install nvimpager symlink to less.sh macro
+app-editors/neovim:remote - Enable support for remote options using nvr
+app-editors/neovim:tui - Build the neovim unix tui
+app-editors/pluma:gtk3 - Build with GTK+3 instead of GTK+2
+app-editors/qhexedit2:gui - Install Qt5 hex editor
+app-editors/tea:aspell - Enable spellchecking using app-text/aspell
+app-editors/tea:hunspell - Enable spellchecking using app-text/hunspell
+app-editors/tea:qml - Enable support for plugins using QML
+app-editors/vim:X - Link console vim against X11 libraries to enable title and clipboard features in xterm
+app-editors/vim:luajit - Use dev-lang/luajit instead of dev-lang/lua
+app-editors/vim:racket - Enable support for Scheme using dev-scheme/racket
+app-editors/vim:terminal - Enable terminal emulation support
+app-editors/vim:vim-pager - Install vimpager and vimmanpager links
+app-editors/vis:tre - more memory efficient regex search using dev-libs/tre
+app-editors/xemacs:athena - Chooses the MIT Athena widget set
+app-editors/xemacs:dnd - Enables support for the x11-libs/dnd drag-n-drop library
+app-editors/xemacs:eolconv - Support detection and translation of newline conventions
+app-editors/xemacs:pop - Support POP for mail retrieval
+app-editors/xemacs:xim - Enable X11 XiM input method
+app-editors/zile:valgrind - Enable usage of dev-util/valgrind in tests
+app-emacs/anything:extensions - Install optional extensions
+app-emacs/auctex:preview-latex - Use bundled preview-latex
+app-emacs/bbdb:tex - Install plain TeX support files
+app-emacs/bbdb:vm - Add support for app-emacs/vm
+app-emacs/calfw:howm - Add support for the app-emacs/howm note-taking tool
+app-emacs/company-mode:ropemacs - Install backend for dev-python/ropemacs
+app-emacs/emacs-common-gentoo:games - Support shared score files for games
+app-emacs/org-mode:contrib - Install user-contributed files
+app-emacs/org-mode:odt-schema - Install non-free schema files for OpenDocument Text exporter
+app-emacs/remember:bbdb - Include support for app-emacs/bbdb
+app-emacs/remember:planner - Include support for app-emacs/planner
+app-emacs/slime:xref - Install xref.lisp cross-referencing tool
+app-emacs/vm:bbdb - Include support for app-emacs/bbdb
+app-emacs/wanderlust:bbdb - Include support for app-emacs/bbdb
+app-emacs/wikipedia-mode:outline-magic - Enable support for outline-mode extensions (app-emacs/outline-magic)
+app-emulation/bochs:3dnow - Enable support for emulating 3DNow! instructions (incomplete)
+app-emulation/bochs:avx - Enable support for emulating Advanced Vector Extensions (AVX)
+app-emulation/bochs:debugger - Enable debugger (slows down emulation)
+app-emulation/bochs:gdb - Enable support for the remote GDB stub
+app-emulation/bochs:x86-64 - Enable support for emulation of 64-bit CPUs
+app-emulation/containerd:btrfs - Support for BTRFS snapshot driver
+app-emulation/crossover-bin:capi - Enable ISDN support via CAPI
+app-emulation/docker:apparmor - Enable AppArmor support.
+app-emulation/docker:aufs - Enables dependencies for the "aufs" graph driver, including necessary kernel flags.
+app-emulation/docker:btrfs - Enables dependencies for the "btrfs" graph driver, including necessary kernel flags.
+app-emulation/docker:container-init - Makes the a staticly-linked init system tini available inside a container.
+app-emulation/docker:device-mapper - Enables dependencies for the "devicemapper" graph driver, including necessary kernel flags.
+app-emulation/docker:overlay - Enables dependencies for the "overlay" graph driver, including necessary kernel flags.
+app-emulation/docker:pkcs11 - Enables pkcs-11 support.
+app-emulation/docker-runc:ambient - Enable support for ambient capability
+app-emulation/docker-runc:apparmor - Enable AppArmor support
+app-emulation/dosemu:fluidsynth - use media-sound/fluidsynth for MIDI emulation
+app-emulation/e-uae:capslib - Add CAPS library support
+app-emulation/e-uae:sdl-sound - Use media-libs/sdl-sound for audio output
+app-emulation/free42:alsa - Adds support for Advanced Linux Sound Architecture
+app-emulation/fuse-utils:gcrypt - Use dev-libs/libgcrypt for low-level crypto of some features, including logfiles.
+app-emulation/ganeti:drbd - Enable DRBD support
+app-emulation/ganeti:experimental - Enable experimental patches. Warning! This will break RPC within major versions if the patches applied differ!
+app-emulation/ganeti:haskell-daemons - Build haskell daemons instead of python
+app-emulation/ganeti:htools - Enable htools support
+app-emulation/ganeti:kvm - Enable KVM support
+app-emulation/ganeti:lxc - Enable Linux Countainers support
+app-emulation/ganeti:monitoring - Enable the ganeti monitoring daemon
+app-emulation/ganeti:multiple-users - Enable support for running VMs as different users
+app-emulation/ganeti:rbd - Enable rados block device support via sys-cluster/ceph
+app-emulation/ganeti:restricted-commands - Enable restricted commands in the node daemon
+app-emulation/ganeti:xen - Enable Xen support
+app-emulation/hyperd:libvirt - Enable support for KVM via libvirt
+app-emulation/hyperd:xen - Enable support for the Xen Hypervisor
+app-emulation/libguestfs:erlang - Build Erlang bindings
+app-emulation/libguestfs:fuse - Enable image mount support via fuse
+app-emulation/libguestfs:inspect-icons - Use media-gfx/icoutilsfor acces icon file in image and inspect it
+app-emulation/libguestfs:systemtap - Use dev-util/systemtap to inspect VM via "probes" way
+app-emulation/libspectrum:gcrypt - Use dev-libs/libgcrypt for low-level crypto of some features, including logfiles.
+app-emulation/libvirt:apparmor - Enable AppArmor support
+app-emulation/libvirt:firewalld - DBus interface to iptables/ebtables allowing for better runtime management of your firewall.
+app-emulation/libvirt:fuse - Allow LXC to use sys-fs/fuse for mount points
+app-emulation/libvirt:glusterfs - Enable GlusterFS support via sys-cluster/glusterfs
+app-emulation/libvirt:iscsi - Allow using an iSCSI remote storage server as pool for disk image storage
+app-emulation/libvirt:libssh - Use net-libs/libssh to communicate with remote libvirtd hosts, for example: qemu+libssh://server/system
+app-emulation/libvirt:libvirtd - Builds the libvirtd daemon as well as the client utilities instead of just the client utilities
+app-emulation/libvirt:lvm - Allow using the Logical Volume Manager (sys-fs/lvm2) as pool for disk image storage
+app-emulation/libvirt:lxc - Support management of Linux Containers virtualisation (app-emulation/lxc)
+app-emulation/libvirt:macvtap - Support for MAC-based TAP (macvlan/macvtap). For networking instead of the normal TUN/TAP. It has its advantages and disadvantages. macvtap support requires very new kernels and is currently evolving. Support for this is experimental at best.
+app-emulation/libvirt:nfs - Allow using Network File System mounts as pool for disk image storage
+app-emulation/libvirt:numa - Use NUMA for memory segmenting via sys-process/numactl and sys-process/numad
+app-emulation/libvirt:openvz - Support management of OpenVZ virtualisation (openvz-sources)
+app-emulation/libvirt:parted - Allow using real disk partitions as pool for disk image storage, using sys-block/parted to create, resize and delete them.
+app-emulation/libvirt:pcap - Support auto learning IP addreses for routing
+app-emulation/libvirt:phyp - Support IBM HMC / IVM hypervisor via PHYP protocol
+app-emulation/libvirt:qemu - Support management of QEMU virtualisation (app-emulation/qemu)
+app-emulation/libvirt:rbd - Enable rados block device support via sys-cluster/ceph
+app-emulation/libvirt:uml - Support management of User Mode Linux virtualisation
+app-emulation/libvirt:vepa - Virtual Ethernet Port Aggregator (VEPA) / 802.1Qbg support. Relies on macvtap support.
+app-emulation/libvirt:virt-network - Enable virtual networking (NAT) support for guests. Includes all the dependencies for NATed network mode. Effectively any network setup that relies on libvirt to setup and configure network interfaces on your host. This can include bridged and routed networks ONLY if you are allowing libvirt to create and manage the underlying devices for you. In some cases this requires enabling the 'netcf' USE flag (currently unavailable).
+app-emulation/libvirt:virtualbox - Support management of VirtualBox virtualisation (one of app-emulation/virtualbox or app-emulation/virtualbox-bin)
+app-emulation/libvirt:wireshark-plugins - Build the net-analyzer/wireshark plugin for the Libvirt RPC protocol
+app-emulation/libvirt:xen - Support management of Xen virtualisation (app-emulation/xen)
+app-emulation/libvirt:zfs - Enable ZFS backend storage sys-fs/zfs
+app-emulation/lxc:cgmanager - Enable support for cgroup management using app-admin/cgmanager
+app-emulation/lxd:daemon - Build the system daemon, not just the client tool
+app-emulation/lxd:dnsmasq - Depend on dnsmasq to provide DHCP and DNS.
+app-emulation/nemu:ovf - Adds support for OVA/OVF import
+app-emulation/nemu:savevm - Adds support for QEMU savevm snapshots (experimental, QEMU must be patched)
+app-emulation/nemu:vnc-client - Adds support for external VNC client
+app-emulation/open-vm-tools:doc - Generate API documentation
+app-emulation/open-vm-tools:grabbitmqproxy - Enable grabbitmqproxy
+app-emulation/open-vm-tools:pic - Force shared libraries to be built as PIC
+app-emulation/open-vm-tools:vgauth - Enable vgauth
+app-emulation/playonlinux:winbind - Enables support for the winbind auth daemon
+app-emulation/punes:cg - Add support for Nvidia CG Toolkit
+app-emulation/q4wine:ico - Enable ico support via media-gfx/icoutils
+app-emulation/q4wine:iso - Support unprivileged mounting of ISO9660 images via sys-fs/fuseiso
+app-emulation/q4wine:wineappdb - Enable Wine AppDB browser support
+app-emulation/qemu:accessibility - Adds support for braille displays using brltty
+app-emulation/qemu:aio - Enables support for Linux's Async IO
+app-emulation/qemu:alsa - Enable alsa output for sound emulation
+app-emulation/qemu:curl - Support ISOs / -cdrom directives vis HTTP or HTTPS.
+app-emulation/qemu:fdt - Enables firmware device tree support
+app-emulation/qemu:glusterfs - Enables GlusterFS cluster fileystem via sys-cluster/glusterfs
+app-emulation/qemu:gnutls - Enable TLS support for the VNC console server. For 1.4 and newer this also enables WebSocket support. For 2.0 through 2.3 also enables disk quorum support.
+app-emulation/qemu:gtk2 - Use gtk-2 instead of gtk-3
+app-emulation/qemu:iscsi - Enable direct iSCSI support via net-libs/libiscsi instead of indirectly via the Linux block layer that sys-block/open-iscsi does.
+app-emulation/qemu:jpeg - Enable jpeg image support for the VNC console server
+app-emulation/qemu:ncurses - Enable the ncurses-based console
+app-emulation/qemu:nfs - Enable NFS support
+app-emulation/qemu:numa - Enable NUMA support
+app-emulation/qemu:pin-upstream-blobs - Pin the versions of BIOS firmware to the version included in the upstream release. This is needed to sanely support migration/suspend/resume/snapshotting/etc... of instances. When the blobs are different, random corruption/bugs/crashes/etc... may be observed.
+app-emulation/qemu:png - Enable png image support for the VNC console server
+app-emulation/qemu:pulseaudio - Enable pulseaudio output for sound emulation
+app-emulation/qemu:rbd - Enable rados block device backend support, see http://ceph.newdream.net/wiki/QEMU-RBD
+app-emulation/qemu:sdl - Enable the SDL-based console
+app-emulation/qemu:sdl2 - Use libsdl2 instead of libsdl
+app-emulation/qemu:snappy - Enable support for snappy compression
+app-emulation/qemu:spice - Enable Spice protocol support via app-emulation/spice
+app-emulation/qemu:ssh - Enable SSH based block device support via net-libs/libssh2
+app-emulation/qemu:static - Build the User and Software MMU (system) targets as well as tools as static binaries
+app-emulation/qemu:static-user - Build the User targets as static binaries
+app-emulation/qemu:systemtap - Enable SystemTAP/DTrace tracing
+app-emulation/qemu:tci - Enable the TCG Interpreter which can speed up or slowdown workloads depending on the host and guest CPUs being emulated. In the future it will be a runtime option but for now its compile time.
+app-emulation/qemu:usb - Enable USB passthrough via dev-libs/libusb
+app-emulation/qemu:usbredir - Use sys-apps/usbredir to redirect USB devices to another machine over TCP
+app-emulation/qemu:vde - Enable VDE-based networking
+app-emulation/qemu:vhost-net - Enable accelerated networking using vhost-net, see http://www.linux-kvm.org/page/VhostNet
+app-emulation/qemu:virgl - Enable experimental Virgil 3d (virtual software GPU)
+app-emulation/qemu:virtfs - Enable VirtFS via virtio-9p-pci / fsdev. See http://wiki.qemu.org/Documentation/9psetup
+app-emulation/qemu:vte - Enable terminal support (x11-libs/vte) in the GTK+ interface
+app-emulation/qemu:xattr - Add support for getting and setting POSIX extended attributes, through sys-apps/attr. Requisite for the virtfs backend.
+app-emulation/qemu:xen - Enables support for Xen backends
+app-emulation/qemu:xfs - Support xfsctl() notification and syncing for XFS backed virtual disks.
+app-emulation/qt-virt-manager:smartcard - Enable smartcard remoting using app-emulation/libcacard
+app-emulation/rkt:actool - Install the actool for ACI manipulation
+app-emulation/rkt:rkt_stage1_coreos - Download and use a prebuilt stage1.aci from CoreOS
+app-emulation/rkt:rkt_stage1_fly - Build stage1-fly.aci
+app-emulation/rkt:rkt_stage1_host - Assemble stage1.aci from host binaries
+app-emulation/rkt:rkt_stage1_kvm - This flag has been replaced by the rkt_stage1_kvm_* flags
+app-emulation/rkt:rkt_stage1_kvm_lkvm - Build stage1-kvm-lkvm.aci
+app-emulation/rkt:rkt_stage1_kvm_qemu - Build stage1-kvm-qemu.aci
+app-emulation/rkt:rkt_stage1_src - Build the stage1.aci from source
+app-emulation/runc:ambient - Enable support for ambient capabilities set (Requires Linux kernel 4.3 or later).
+app-emulation/runc:apparmor - Enable AppArmor support.
+app-emulation/runv:libvirt - Enable support for KVM via libvirt
+app-emulation/runv:xen - Enable support for the Xen Hypervisor
+app-emulation/spice:lz4 - Enable support for LZ4 compression using app-arch/lz4
+app-emulation/spice:smartcard - Enable smartcard remoting using app-emulation/libcacard
+app-emulation/spice-vdagent:consolekit - Use sys-auth/consolekit to determine the master vdagentd in case of multiple running vdagentds (highly recommended)
+app-emulation/uae:scsi - Enable the uaescsi.device
+app-emulation/vagrant:virtualbox - Use VirtualBox provider.
+app-emulation/vice:ethernet - Enable ethernet emulation
+app-emulation/vice:fullscreen - Enable the ability to run fullscreen
+app-emulation/vice:sdlsound - Use media-libs/libsdl for sound support
+app-emulation/vice:vte - Enable support for x11-libs/vte in the GTK+ interface
+app-emulation/virt-manager:policykit - Enables sys-auth/polkit authentication support, required when using app-emulation/libvirt with PolicyKit authentication
+app-emulation/virt-manager:sasl - Depend on the proper libraries needed to connect to SASL-enabled libvirtd instances (e.g. Kerberos-protected instances).
+app-emulation/virt-viewer:spice - Support connecting to SPICE-enabled virtual machines.
+app-emulation/virt-viewer:vnc - Support connecting to VNC-enabled virtual machines.
+app-emulation/virt-what:dmi - Use sys-apps/dmidecode to read firmware data
+app-emulation/virtualbox:headless - Build without any graphic frontend
+app-emulation/virtualbox:lvm - Build VBoxVolInfo that needs devicemapper from sys-fs/lvm2.
+app-emulation/virtualbox:pax_kernel - Apply patch needed for pax enabled kernels.
+app-emulation/virtualbox:sdk - Enable building of SDK
+app-emulation/virtualbox:udev - Controls installation of special USB udev rules.
+app-emulation/virtualbox:vboxwebsrv - Build and install the VirtualBox webservice
+app-emulation/virtualbox-bin:additions - Install Guest System Tools ISO
+app-emulation/virtualbox-bin:chm - Install kchmviewer binary to enable online help (in MS CHM format)
+app-emulation/virtualbox-bin:headless - Install without any graphic frontend
+app-emulation/virtualbox-bin:rdesktop-vrdp - Install the rdesktop client integration
+app-emulation/virtualbox-bin:sdk - Enable building of SDK
+app-emulation/virtualbox-bin:vboxwebsrv - Install the VirtualBox webservice
+app-emulation/virtualbox-modules:pax_kernel - Apply patch needed for pax enabled kernels
+app-emulation/vov:gprof - build with profiling support
+app-emulation/wine-any:capi - Enable ISDN support via CAPI
+app-emulation/wine-any:custom-cflags - Bypass strip-flags; use at your own peril
+app-emulation/wine-any:d3d9 - Apply highly experimental patches for Gallium Nine support. This patch may break some applications.
+app-emulation/wine-any:dos - Pull in games-emulation/dosbox to run DOS applications
+app-emulation/wine-any:gecko - Add support for the Gecko engine when using iexplore
+app-emulation/wine-any:gssapi - Use GSSAPI (Kerberos SSP support)
+app-emulation/wine-any:gstreamer - Use media-libs/gstreamer to provide DirectShow functionality;
+app-emulation/wine-any:mono - Add support for .NET using Wine's Mono add-on
+app-emulation/wine-any:netapi - Use libnetapi from net-fs/samba to support Windows networks in netapi32.dll
+app-emulation/wine-any:opencl - Enable OpenCL support
+app-emulation/wine-any:osmesa - Add support for OpenGL in bitmaps using libOSMesa
+app-emulation/wine-any:pcap - Support packet capture software (e.g. wireshark)
+app-emulation/wine-any:perl - Install helpers written in perl (winedump/winemaker)
+app-emulation/wine-any:pipelight - Apply Wine-Staging patches for Pipelight/Silverlight support
+app-emulation/wine-any:prelink - Run prelink on DLLs during build; For versions before wine-1.7.55 or hardened, do not disable if you do not know what this means as it can break things at runtime
+app-emulation/wine-any:realtime - Pull in sys-auth/rtkit for low-latency pulseaudio support
+app-emulation/wine-any:run-exes - Use Wine to open and run .EXE and .MSI files
+app-emulation/wine-any:s3tc - Pull in media-libs/libtxc_dxtn for DXTn texture compression, needed for many games
+app-emulation/wine-any:samba - Add support for NTLM auth. see http://wiki.winehq.org/NtlmAuthSetupGuide and http://wiki.winehq.org/NtlmSigningAndSealing
+app-emulation/wine-any:staging - Apply Wine-Staging patches for advanced feature support that haven't made it into upstream Wine yet
+app-emulation/wine-any:themes - Support GTK+:3 window theming through Wine-Staging
+app-emulation/wine-any:udev - Use virtual/libudev to provide plug and play support
+app-emulation/wine-any:vulkan - Enable Vulkan drivers
+app-emulation/wine-d3d9:capi - Enable ISDN support via CAPI
+app-emulation/wine-d3d9:custom-cflags - Bypass strip-flags; use at your own peril
+app-emulation/wine-d3d9:d3d9 - Apply highly experimental patches for Gallium Nine support. This patch may break some applications.
+app-emulation/wine-d3d9:dos - Pull in games-emulation/dosbox to run DOS applications
+app-emulation/wine-d3d9:gecko - Add support for the Gecko engine when using iexplore
+app-emulation/wine-d3d9:gssapi - Use GSSAPI (Kerberos SSP support)
+app-emulation/wine-d3d9:gstreamer - Use media-libs/gstreamer to provide DirectShow functionality;
+app-emulation/wine-d3d9:mono - Add support for .NET using Wine's Mono add-on
+app-emulation/wine-d3d9:netapi - Use libnetapi from net-fs/samba to support Windows networks in netapi32.dll
+app-emulation/wine-d3d9:opencl - Enable OpenCL support
+app-emulation/wine-d3d9:osmesa - Add support for OpenGL in bitmaps using libOSMesa
+app-emulation/wine-d3d9:pcap - Support packet capture software (e.g. wireshark)
+app-emulation/wine-d3d9:perl - Install helpers written in perl (winedump/winemaker)
+app-emulation/wine-d3d9:prelink - Run prelink on DLLs during build; For versions before wine-1.7.55 or hardened, do not disable if you do not know what this means as it can break things at runtime
+app-emulation/wine-d3d9:realtime - Pull in sys-auth/rtkit for low-latency pulseaudio support
+app-emulation/wine-d3d9:run-exes - Use Wine to open and run .EXE and .MSI files
+app-emulation/wine-d3d9:samba - Add support for NTLM auth. see http://wiki.winehq.org/NtlmAuthSetupGuide and http://wiki.winehq.org/NtlmSigningAndSealing
+app-emulation/wine-d3d9:udev - Use virtual/libudev to provide plug and play support
+app-emulation/wine-d3d9:vulkan - Enable Vulkan drivers
+app-emulation/wine-staging:capi - Enable ISDN support via CAPI
+app-emulation/wine-staging:custom-cflags - Bypass strip-flags; use at your own peril
+app-emulation/wine-staging:dos - Pull in games-emulation/dosbox to run DOS applications
+app-emulation/wine-staging:gecko - Add support for the Gecko engine when using iexplore
+app-emulation/wine-staging:gssapi - Use GSSAPI (Kerberos SSP support)
+app-emulation/wine-staging:gstreamer - Use media-libs/gstreamer to provide DirectShow functionality;
+app-emulation/wine-staging:mono - Add support for .NET using Wine's Mono add-on
+app-emulation/wine-staging:netapi - Use libnetapi from net-fs/samba to support Windows networks in netapi32.dll
+app-emulation/wine-staging:opencl - Enable OpenCL support
+app-emulation/wine-staging:osmesa - Add support for OpenGL in bitmaps using libOSMesa
+app-emulation/wine-staging:pcap - Support packet capture software (e.g. wireshark)
+app-emulation/wine-staging:perl - Install helpers written in perl (winedump/winemaker)
+app-emulation/wine-staging:pipelight - Apply Wine-Staging patches for Pipelight/Silverlight support
+app-emulation/wine-staging:prelink - Run prelink on DLLs during build; For versions before wine-1.7.55 or hardened, do not disable if you do not know what this means as it can break things at runtime
+app-emulation/wine-staging:realtime - Pull in sys-auth/rtkit for low-latency pulseaudio support
+app-emulation/wine-staging:run-exes - Use Wine to open and run .EXE and .MSI files
+app-emulation/wine-staging:s3tc - Pull in media-libs/libtxc_dxtn for DXTn texture compression, needed for many games
+app-emulation/wine-staging:samba - Add support for NTLM auth. see http://wiki.winehq.org/NtlmAuthSetupGuide and http://wiki.winehq.org/NtlmSigningAndSealing
+app-emulation/wine-staging:staging - Apply Wine-Staging patches for advanced feature support that haven't made it into upstream Wine yet
+app-emulation/wine-staging:themes - Support GTK+:3 window theming through Wine-Staging
+app-emulation/wine-staging:udev - Use virtual/libudev to provide plug and play support
+app-emulation/wine-staging:vulkan - Enable Vulkan drivers
+app-emulation/wine-vanilla:capi - Enable ISDN support via CAPI
+app-emulation/wine-vanilla:custom-cflags - Bypass strip-flags; use at your own peril
+app-emulation/wine-vanilla:dos - Pull in games-emulation/dosbox to run DOS applications
+app-emulation/wine-vanilla:gecko - Add support for the Gecko engine when using iexplore
+app-emulation/wine-vanilla:gssapi - Use GSSAPI (Kerberos SSP support)
+app-emulation/wine-vanilla:gstreamer - Use media-libs/gstreamer to provide DirectShow functionality;
+app-emulation/wine-vanilla:mono - Add support for .NET using Wine's Mono add-on
+app-emulation/wine-vanilla:netapi - Use libnetapi from net-fs/samba to support Windows networks in netapi32.dll
+app-emulation/wine-vanilla:opencl - Enable OpenCL support
+app-emulation/wine-vanilla:osmesa - Add support for OpenGL in bitmaps using libOSMesa
+app-emulation/wine-vanilla:pcap - Support packet capture software (e.g. wireshark)
+app-emulation/wine-vanilla:perl - Install helpers written in perl (winedump/winemaker)
+app-emulation/wine-vanilla:prelink - Run prelink on DLLs during build; For versions before wine-1.7.55 or hardened, do not disable if you do not know what this means as it can break things at runtime
+app-emulation/wine-vanilla:realtime - Pull in sys-auth/rtkit for low-latency pulseaudio support
+app-emulation/wine-vanilla:run-exes - Use Wine to open and run .EXE and .MSI files
+app-emulation/wine-vanilla:samba - Add support for NTLM auth. see http://wiki.winehq.org/NtlmAuthSetupGuide and http://wiki.winehq.org/NtlmSigningAndSealing
+app-emulation/wine-vanilla:udev - Use virtual/libudev to provide plug and play support
+app-emulation/wine-vanilla:vulkan - Enable Vulkan drivers
+app-emulation/winetricks:rar - Pull in app-arch/unrar for extraction of rar-compressed game files
+app-emulation/x48:readline - Enables support for libreadline
+app-emulation/xe-guest-utilities:xenstore - Use xenstore binaries bundled by Citrix instead of building app-emulation/xen-tools
+app-emulation/xen:efi - Adds efi boot support, requires LDFLAG -melf_x86_64 for amd64
+app-emulation/xen:flask - Enable the Flask XSM module from NSA
+app-emulation/xen-tools:api - Build the C libxenapi bindings
+app-emulation/xen-tools:flask - Enable the Flask XSM module from NSA
+app-emulation/xen-tools:hvm - Enable support for hardware based virtualization (VT-x,AMD-v)
+app-emulation/xen-tools:ocaml - Enable support for the ocaml language
+app-emulation/xen-tools:ovmf - Enable support to boot UEFI guest vm, needed by hvm
+app-emulation/xen-tools:pam - Enable pam support
+app-emulation/xen-tools:pygrub - Install the pygrub boot loader
+app-emulation/xen-tools:qemu - Enable IOEMU support via the use of qemu-dm
+app-emulation/xen-tools:qemu-traditional - Build the old qemu traditional device model (useful only if you cannot change to the new device model e.g. Windows VMs)
+app-emulation/xen-tools:screen - Enable support for running domain U console in an app-misc/screen session
+app-emulation/xen-tools:system-qemu - Using app-emulation/qemu instead of the bundled one
+app-emulation/xen-tools:system-seabios - Using sys-firmware/seabios instead of the bundled one
+app-emulation/xtrs:ls-dos - Install LS-DOS disk images for Model 4P
+app-eselect/eselect-php:fpm - Enable the FastCGI Process Manager SAPI
+app-forensics/afflib:fuse - Enable extra fuse thingies
+app-forensics/afflib:qemu - Enable qemu stuff
+app-forensics/afflib:s3 - Enable support for Amazon S3
+app-forensics/aide:e2fs - Enable support for checking file attributes on ext2/ext3/ext4 filesystems
+app-forensics/aide:prelink - Bypass prelinking when calculating checksums
+app-forensics/chkrootkit:cron - Install cron script for weekly rootkit scans
+app-forensics/libewf:bfio - Enables libbfio for chaining file in file handling
+app-forensics/libewf:ewf - Enables the v1 API
+app-forensics/libewf:fuse - Enable fuse support for ewfmount
+app-forensics/libewf:rawio - Enables raw IO handling
+app-forensics/libewf:uuid - Enable UUID support in the ewftools
+app-forensics/openscap:gconf - Build the gconf independant probes
+app-forensics/openscap:nss - Prefer NSS over libgcrypt as the crypto engine
+app-forensics/openscap:rpm - Compiles the RPM probes
+app-forensics/openscap:sce - Enables Script Check Engine (SCE) support
+app-forensics/openscap:sql - Build the sql independant probes
+app-forensics/quickfuzz:archs - support archive formats
+app-forensics/quickfuzz:codes - support cource code formats
+app-forensics/quickfuzz:docs - support document formats
+app-forensics/quickfuzz:imgs - support image formats
+app-forensics/quickfuzz:media - support media formats
+app-forensics/quickfuzz:net - support networking formats
+app-forensics/quickfuzz:pki - support PKI formats
+app-forensics/sleuthkit:aff - Enable extra aff formats
+app-forensics/sleuthkit:ewf - Enable libewf support
+app-i18n/anthy:canna-2ch - Enable support for app-dicts/canna-2ch
+app-i18n/canna:canuum - Build canuum
+app-i18n/fcitx:autostart - Enable XDG-compatible autostart of Fcitx
+app-i18n/fcitx:enchant - Enable Enchant backend (using app-text/enchant) for spelling hinting
+app-i18n/fcitx:gtk2 - Install input method module for GTK+ 2
+app-i18n/fcitx:gtk3 - Install input method module for GTK+ 3
+app-i18n/fcitx:opencc - Enable OpenCC engine (using app-i18n/opencc) for converter between Simplified Chinese and Traditional Chinese
+app-i18n/fcitx:pango - Enable support for x11-libs/pango
+app-i18n/fcitx:qt4 - Install input method module for Qt 4
+app-i18n/fcitx:table - Install table input methods for Simplified Chinese
+app-i18n/fcitx-libpinyin:dictionary-manager - Install dictionary manager
+app-i18n/fcitx-unikey:macro-editor - Install macro editor
+app-i18n/freewnn:uum - Build uum
+app-i18n/ibus:emoji - Enable support for Emoji
+app-i18n/ibus:gconf - Enable support for gnome-base/gconf
+app-i18n/ibus:gtk2 - Enable support for x11-libs/gtk+:2
+app-i18n/ibus-chewing:gconf - Enable support for gnome-base/gconf
+app-i18n/ibus-handwrite:zinnia - Enable support for app-i18n/zinnia
+app-i18n/ibus-libpinyin:boost - Compile against dev-libs/boost libraries
+app-i18n/ibus-libpinyin:opencc - Enable support for app-i18n/opencc
+app-i18n/ibus-m17n:gtk2 - Build with x11-libs/gtk+:2 instead of x11-libs/gtk+:3
+app-i18n/ibus-pinyin:boost - Enable support for dev-libs/boost
+app-i18n/ibus-unikey:gtk2 - Enable support for x11-libs/gtk+:2
+app-i18n/im-chooser:gtk2 - Build with x11-libs/gtk+:2 instead of x11-libs/gtk+:3
+app-i18n/im-chooser:xfce - Enable support for XFCE panel
+app-i18n/imsettings:gconf - Enable support for gnome-base/gconf
+app-i18n/imsettings:gtk2 - Build with x11-libs/gtk+:2 instead of x11-libs/gtk+:3
+app-i18n/imsettings:xfconf - Enable support for xfce-base/xfconf
+app-i18n/mozc:fcitx4 - Enable support for app-i18n/fcitx 4
+app-i18n/mozc:gui - Install graphical user interface tool (mozc_tool)
+app-i18n/mozc:handwriting-tegaki - Use handwriting recognition model from app-i18n/tegaki-zinnia-japanese
+app-i18n/mozc:handwriting-tomoe - Use handwriting recognition model from app-i18n/zinnia-tomoe
+app-i18n/mozc:ibus - Enable support for app-i18n/ibus
+app-i18n/mozc:renderer - Enable native candidate window
+app-i18n/pyzy:boost - Enable support for dev-libs/boost
+app-i18n/pyzy:doc - Generate API documentation
+app-i18n/pyzy:opencc - Enable support for app-i18n/opencc
+app-i18n/scim:gtk3 - Enable support for x11-libs/gtk+:3
+app-i18n/scim-anthy:gtk3 - Enable support for x11-libs/gtk+:3
+app-i18n/scim-anthy:kasumi - Use Anthy dictionary maintenance tool (app-dicts/kasumi)
+app-i18n/tomoe:hyperestraier - Enable support for app-text/hyperestraier
+app-i18n/translate-shell:tts - Enable text-to-speech support
+app-i18n/uim:anthy - Enable support for app-i18n/anthy input method
+app-i18n/uim:eb - Enable support for dev-libs/eb
+app-i18n/uim:gtk3 - Enable support for x11-libs/gtk+:3
+app-i18n/uim:skk - Enable support for app-i18n/skk-jisyo
+app-laptop/hdapsd:libconfig - Require dev-libs/libconfig to allow the daemon to read a configuration file at startup
+app-laptop/ibam:gkrellm - Enable building of app-admin/gkrellm module
+app-laptop/pbbuttonsd:ibam - Enable support for Intelligent Battery Monitoring
+app-laptop/pbbuttonsd:macbook - Enable support for the Macbook and Macbook Pro
+app-laptop/thinkfan:atasmart - include libatasmart support to get disc temperature
+app-laptop/tp_smapi:hdaps - Install a compatible HDAPS module
+app-leechcraft/lc-azoth:acetamide - Build Acetamide, the IRC protocol support
+app-leechcraft/lc-azoth:adiumstyles - Build support for Adium styles
+app-leechcraft/lc-azoth:astrality - Build Astrality, support for protocols provided by Telepathy
+app-leechcraft/lc-azoth:autoidler - Build support for automatic status changing according to user idle time
+app-leechcraft/lc-azoth:autopaste - Build Autopaste for pasting long texts to pastebins
+app-leechcraft/lc-azoth:birthdaynotifier - Build Birthday Notifier for you to not forget about birthdays of your contacts.
+app-leechcraft/lc-azoth:chathistory - Build ChatHistory which stories chat history
+app-leechcraft/lc-azoth:depester - Build Depester which enables to ignore MUC participants
+app-leechcraft/lc-azoth:embedmedia - Build EmbedMedia for embedding flash videos and images directly into chat windows
+app-leechcraft/lc-azoth:herbicide - Build Herbicide, a basic antispam plugin
+app-leechcraft/lc-azoth:hili - Build HiLi which allows to customize highlight settings in MUCs
+app-leechcraft/lc-azoth:isterique - Build Isterique plugin for neutralizing excessive caps lock usage
+app-leechcraft/lc-azoth:juick - Build plugin for the Juick.com microblogging service
+app-leechcraft/lc-azoth:keeso - Build plugin for changing text into SoMEtHInG lIKe THiS
+app-leechcraft/lc-azoth:lastseen - Build plugin for client-side recording of the last online/available time
+app-leechcraft/lc-azoth:media - Enable media calls
+app-leechcraft/lc-azoth:metacontacts - Build plugin for metacontacts support
+app-leechcraft/lc-azoth:murm - Build Murm, the VKontakte messaging support via their native API (instead of XMPP)
+app-leechcraft/lc-azoth:nativeemoticons - Build support for native Azoth's emoticons packs
+app-leechcraft/lc-azoth:otroid - Build OTRoid, plugin for the Off-the-Record deniable encryption system
+app-leechcraft/lc-azoth:sarin - Build Sarin, Tox protocol support module. Please add mva overlay to use net-libs/tox
+app-leechcraft/lc-azoth:shx - Build shell command executor plugin
+app-leechcraft/lc-azoth:standardstyles - Build support for standard Azoth styles engine
+app-leechcraft/lc-azoth:vader - Bulid Vader, the MRIM (Mail.Ru Agent) protocol support plugin
+app-leechcraft/lc-azoth:velvetbird - Build support for protocols provided by libpurple
+app-leechcraft/lc-azoth:woodpecker - Build Woodpecker, the Twitter client plugin
+app-leechcraft/lc-azoth:xtazy - Build Xtazy for publishing currently playing tune
+app-leechcraft/lc-blasq:deathnote - Support LiveJournal FotoBilder service
+app-leechcraft/lc-blasq:rappor - Support VKontakte service
+app-leechcraft/lc-blasq:spegnersi - Support Flickr service
+app-leechcraft/lc-blasq:vangog - Support Picasa service
+app-leechcraft/lc-blogique:hestia - Allows one to keep a local blog
+app-leechcraft/lc-blogique:metida - Support for the LiveJournal blogging platform
+app-leechcraft/lc-core:qwt - Support for QML plotting item through x11-libs/qwt
+app-leechcraft/lc-gmailnotifier:notify - Pull in a plugin to show notifications from GMail Notiifer
+app-leechcraft/lc-gmailnotifier:quark - Pull in a plugin to show GMail Notifier's quark
+app-leechcraft/lc-lmp:fradj - Build FrAdj, the equalizer effect module
+app-leechcraft/lc-lmp:graffiti - Build media tags editor plugin
+app-leechcraft/lc-lmp:guess - Enable tags encoding guessing via the libguess library
+app-leechcraft/lc-lmp:mp3tunes - Build plugin for supporting the mp3tunes.com music locker service
+app-leechcraft/lc-lmp:mpris - Enable MPRIS support
+app-leechcraft/lc-lmp:potorchu - Enable the projectM-based visualization effects module for LMP
+app-leechcraft/lc-monocle:fb2 - Enable support for FictionBook format
+app-leechcraft/lc-monocle:mobi - Enable support for MOBI format
+app-leechcraft/lc-musiczombie:acoustid - Use media-libs/chromaprint for acoustic fingerprinting
+app-leechcraft/lc-netstoremanager:dropbox - Build Dropbox storage backend
+app-leechcraft/lc-netstoremanager:googledrive - Build Google Drive storage backend
+app-leechcraft/lc-poshuku:autosearch - Provide automatic search suggestions for Poshuku.
+app-leechcraft/lc-poshuku:cleanweb - Build CleanWeb for ad blocking compatible with Firefox's AdBlock+.
+app-leechcraft/lc-poshuku:dcac - Build color inverter module providing a night mode.
+app-leechcraft/lc-poshuku:fatape - Build FatApe, GreaseMonkey userscripts support layer.
+app-leechcraft/lc-poshuku:filescheme - Build FileScheme for accessing local URLs.
+app-leechcraft/lc-poshuku:foc - Build FOC for Flash-on-Click functionality.
+app-leechcraft/lc-poshuku:fua - Build FUA for faking user agents for different hosts.
+app-leechcraft/lc-poshuku:keywords - Build Keywords for adjusting search shortcuts.
+app-leechcraft/lc-poshuku:onlinebookmarks - Build OnlineBookmarks for syncing bookmarks with social bookmarking services like Read It Later.
+app-leechcraft/lc-poshuku:qrd - Build module for displaying the QR code of a web page.
+app-leechcraft/lc-poshuku:speeddial - Build SpeedDial module.
+app-leechcraft/lc-poshuku:webengine - Build WebEngine- (that is, Chromium-)based rendering backend.
+app-leechcraft/lc-secman:exposecontents - Build the GUI for viewing the stored data.
+app-leechcraft/leechcraft-meta:de - Install components, that allow using Leechcraft as Desktop Environment
+app-misc/anki:recording - Enable support for audio recording
+app-misc/anki:sound - Enable support for adding sound to cards
+app-misc/binwalk:graph - Enable support for generating entropy graphs
+app-misc/blink1:mini-tool - Build and install command-line mini-tool blink1-mini-tool (normally used for embedded devices)
+app-misc/blink1:server - Build and install REST API server (currently hard-coded to TCP port 8080)
+app-misc/blink1:tool - Build and install command-line tool blink1-tool
+app-misc/byobu:screen - Use app-misc/screen as the default backend
+app-misc/ca-certificates:cacert - Include root certificates from CAcert (http://www.cacert.org/) and Software in the Public Interest (http://www.spi-inc.org/)
+app-misc/ca-certificates:insecure_certs - Install certificates which are known to be untrustworthy.
+app-misc/carbon-c-relay:lz4 - add support for LZ4 compressed transport
+app-misc/ddccontrol:pci - enable direct PCI memory access (the setuid ddcpci util)
+app-misc/ddcutil:drm - Use x11-libs/libdrm for more verbose diagnostics.
+app-misc/ddcutil:usb-monitor - Adds support for monitors attached via USB.
+app-misc/ddcutil:user-permissions - Adds a udev rules to allow non-root users in the i2c group to access the /dev/i2c-* devices. If usb-monitor is selected, users will need to be added to the video group to access the USB monitor. Otherwise, only root will be able to use ddcutil.
+app-misc/digitemp:ds2490 - Build support for the ds2490 sensor
+app-misc/digitemp:ds9097 - Build support for the ds9097 sensor
+app-misc/digitemp:ds9097u - Build support for the ds9097u sensor
+app-misc/emelfm2:ansi - Add support for ANSI escape sequences
+app-misc/emelfm2:gtk3 - Use x11-libs/gtk+:3 instead of x11-libs/gtk+:2
+app-misc/freemind:groovy - Build plugin for scripting via Groovy
+app-misc/freemind:latex - Build plugin for inserting mathematical formulas in LaTeX syntax
+app-misc/freemind:pdf - Build plugin for exporting mindmaps to SVG and PDF
+app-misc/freemind:svg - Build plugin for exporting mindmaps to SVG and PDF
+app-misc/gcstar:stats - Enable statistics reporting
+app-misc/gcstar:tellico - Enable support for kde-misc/tellico files
+app-misc/geoclue:geonames - Install geonames.org provider
+app-misc/geoclue:gsmloc - Install GSM location provider
+app-misc/geoclue:gtk - Install gtk-based geoclue-test-gui
+app-misc/geoclue:hostip - Install hostip.info provder
+app-misc/geoclue:manual - Install manual provider
+app-misc/geoclue:modemmanager - Enable geolocation through 3G or GPS enabled hardware through net-misc/modemmanager.
+app-misc/geoclue:nominatim - Install openstreetmap.org provider
+app-misc/geoclue:plazes - Install plazes.com provider
+app-misc/geoclue:skyhook - Install skyhookwireless.com provider
+app-misc/geoclue:yahoo-geo - Install Yahoo geolocation provider
+app-misc/geoclue:zeroconf - Enable retrieval of GPS location from Android devices with https://wiki.gnome.org/Apps/GeoclueShare
+app-misc/gourmet:i18n - Enable support for i18n through elib.intl
+app-misc/gourmet:ipython - Enable support for the interactive Python console plugin
+app-misc/gourmet:pdf - Enable export to PDF
+app-misc/gourmet:print - Enable pretty Python printing
+app-misc/gourmet:spell - Enable support for the spell check plugin
+app-misc/gourmet:web - Enable support for the web import plugin
+app-misc/gramps:geo - Enable rendering of geographical data using sci-geosciences/osm-gps-map
+app-misc/gramps:reports - All external software that is needed for graphical reports will be installed
+app-misc/graphlcd-base:g15 - Add support for app-misc/g15daemon driver (e.g. Logitech G15 Keybord)
+app-misc/irtrans-irserver:mono - Enable mono support
+app-misc/jq:oniguruma - Use dev-libs/oniguruma for regular expression support
+app-misc/lcd4linux:mpd - Add support for display of mpd controlled music (media-libs/libmpd)
+app-misc/lcdproc:ftdi - Enable support for FTDI connections in some selected LCD_DEVICES (currently hd44780)
+app-misc/lcdproc:hid - Enable HID support using libhid
+app-misc/lcdproc:irman - Enable support for IRMan (media-libs/libirman)
+app-misc/lcdproc:lcd_devices_sdeclcd - Enable support for VLSYS M428 display
+app-misc/lcdproc:lcd_devices_vlsys_m428 - Enable support for VLSYS M428 display
+app-misc/lcdproc:nfs - Adds support for NFS file system
+app-misc/lcdproc:seamless-hbars - Try to avoid gaps in horizontal bars
+app-misc/lirc:audio - Support using an audio device connected to an IR receiver
+app-misc/lirc:devinput - Support the devinput input device
+app-misc/lirc:ftdi - Support FTDI devices
+app-misc/lirc:gtk - Include GTK support which enables the use of lirc-setup
+app-misc/lirc:hardware-carrier - The transmitter device generates its clock signal in hardware
+app-misc/lirc:iguanair - Support iguanaIR devices
+app-misc/lirc:inputlirc - Add a dependency on app-misc/inputlircd
+app-misc/lirc:irman - Add a dependency on media-libs/libirman
+app-misc/lirc:transmitter - Add transmitter support to some lirc-drivers (e.g. serial)
+app-misc/lirc:uinput - Enable support for uinput
+app-misc/mc:edit - Compile and install the mcedit application
+app-misc/mc:mclib - Compile and install the libmc.so shared library
+app-misc/mc:sftp - Add support for sftp (uses net-libs/libssh2 for it).
+app-misc/mc:slang - Use sys-libs/slang instead of sys-libs/ncurses.
+app-misc/mc:xdg - Toggles mc's config dir location. Enable for $XDG_CONFIG_HOME/mc, disable for $HOME/.mc
+app-misc/mosquitto:bridge - Enable bridge support in the MQTT broker.
+app-misc/mosquitto:persistence - Store messages and subscriptions to a file.
+app-misc/mosquitto:srv - Include SRV lookup support.
+app-misc/mosquitto:websockets - Support the WebSocket protocol.
+app-misc/muttprint:doc - Builds documentation
+app-misc/neofetch:X - Enable support for detecting DEs, WMs, screen resolutions, and showing images from an X terminal
+app-misc/nnn:fish-completion - Enable fish completion support
+app-misc/note:general - Add support for ascii flatfile backend
+app-misc/note:text - Add support for text backend
+app-misc/openastro:jpeg - Enable exporting Astrological Charts to jpeg
+app-misc/openastro:png - Enable exporting Astrological Charts to png
+app-misc/pax-utils:python - Install a more powerful/faster version of lddtree
+app-misc/recoll:camelcase - Enable indexing for camelCase sentences and words
+app-misc/recoll:inotify - Use the Linux Kernel notification subsystem for monitoring file alterations in realtime
+app-misc/recoll:session - Stop monitoring file alterations when X11 session terminates
+app-misc/rlwrap:debug - Enable debug
+app-misc/screen:multiuser - Enable multiuser support (by setting correct permissions)
+app-misc/screen:nethack - Express error messages in nethack style
+app-misc/screen:utmp - Include utmp support
+app-misc/screenfetch:X - Use the media-gfx/scrot package to take screenshots
+app-misc/sphinx:id64 - use 64-bit document and word IDs
+app-misc/sphinx:re2 - use the dev-libs/re2 regular expression library
+app-misc/sphinx:stemmer - Enable language stemming support
+app-misc/task:sync - Enable "task sync" support
+app-misc/tmux:utempter - Include libutempter support
+app-misc/towitoko:moneyplex - Makes libtowitoko work for the moneyplex home banking software
+app-misc/tracker:cue - Enable cue sheet parsing
+app-misc/tracker:firefox-bookmarks - Install bookmark data miner plugin for www-client/firefox and www-client/firefox-bin
+app-misc/tracker:gsf - Enable gnome-extra/libgsf based data extractor and for ODT.
+app-misc/tracker:iptc - Enable extraction of IPTC data from pictures
+app-misc/tracker:iso - Enable extraction of metadata from ISO disk images
+app-misc/tracker:miner-fs - Enable tracker-miner-fs (required for filesystem indexing)
+app-misc/tracker:nautilus - Enable tracker to integrate with gnome-base/nautilus by providing entries in its context menu
+app-misc/tracker:playlist - Add support for playlists
+app-misc/tracker:stemmer - Add word stemming via dev-libs/snowball-stemmer.
+app-misc/tracker:thunderbird - Install email data miner plugin for mail-client/thunderbird and mail-client/thunderbird-bin
+app-misc/tracker:xps - Add support for XPS file format through app-text/libgxps.
+app-misc/unfoo:minimal - Do not install all support archive binaries
+app-misc/vcontrold:man - Build the manpages
+app-misc/vcontrold:vclient - Build the vclient helper program to talk to vcontrold
+app-misc/vcontrold:vsim - Build the vsim helper program (simulates the heating's answers, for development and debugging)
+app-misc/vifm:X - Add support for X11
+app-misc/vifm:compatibility - Compatibility with previous versions of vifm
+app-misc/vifm:developer - Enable features of interest to developers
+app-misc/vifm:extended-keys - Support for extended keys (arrows, home etc)
+app-misc/vifm:gtk - Use gtk+ to determine mimetypes
+app-misc/vifm:magic - Use libmagic to determine mimetypes
+app-misc/vifm:vim - Install the vifm vim plugin and vim-compatible documentation
+app-misc/vifm:vim-plugin - Install the vifm vim plugin
+app-misc/vifm:vim-syntax - Pulls in related vim syntax scripts
+app-misc/worker:avfs - Enable support for sys-fs/avfs
+app-misc/worker:magic - Add magic file support from sys-apps/file to automatically detect file types
+app-misc/workrave:mate - Add support for MATE panel
+app-misc/workrave:xfce - Add support for XFCE panel
+app-misc/zygrib:maps - Installs additional GSHHS maps for high resolution coastline data and cities
+app-mobilephone/gammu:bluetooth - Enables bluetooth support
+app-mobilephone/gammu:curl - Enables curl support
+app-mobilephone/gammu:irda - Enables infrared support
+app-mobilephone/gammu:mysql - Use mysql for data storage
+app-mobilephone/gammu:nls - Enable native language support
+app-mobilephone/gammu:odbc - Use ODBC as DB connector
+app-mobilephone/gammu:postgres - Use PostgreSQL for data storage
+app-mobilephone/gammu:usb - Enable USB suport
+app-mobilephone/gnokii:ical - Enable support for dev-libs/libical
+app-mobilephone/gnokii:irda - Enable infrared support
+app-mobilephone/gnokii:pcsc-lite - Enable smartcard support with sys-apps/pcsc-lite
+app-mobilephone/gnokii:sms - Enable SMS support (build smsd)
+app-mobilephone/smstools:stats - Enable statistic reporting
+app-office/abiword:collab - Enable collaborative editing plugin
+app-office/abiword:goffice - Enable goffice plugin
+app-office/abiword:grammar - Enable grammar checking via dev-libs/link-grammar
+app-office/abiword:map - Enable world map support through media-libs/libchamplain
+app-office/abiword:math - Enable support for x11-libs/gtkmathview
+app-office/abiword:ots - Enable Text Summarizer plugin
+app-office/abiword:plugins - Enable plugins build (see http://www.abisource.com/wiki/PluginMatrix for more information). If your file cannot be opened due lack of support, try enabling this.
+app-office/abiword:redland - Enables support redland and raptor libs.
+app-office/abiword:thesaurus - Enable thesaurus support
+app-office/abiword:wordperfect - Enable wordperfect file support via app-text/libwpd
+app-office/calligra:activities - Enable kactivities support
+app-office/calligra:gemini - Enable tablet and 2:1 devices support
+app-office/calligra:import-filter - Enable support for various import filter file formats like WordPerfect, Visio and Apple Keynote
+app-office/calligra:lcms - Build colorengine plugins using media-libs/lcms
+app-office/calligra:okular - Enable bindings for kde-apps/okular
+app-office/calligra:phonon - Build stage/eventplugins and videoshape plugin using media-libs/phonon
+app-office/calligra:pim - Enable support for KDE PIM resources integration
+app-office/calligra:spacenav - Enable support for the 3Dconnexion spacenav input device via dev-libs/libspnav
+app-office/glabels:barcode - Enable barcode support through external libraries.
+app-office/gnucash:aqbanking - Connect to some internet banks via AqBanking
+app-office/gnucash:chipcard - Enable support for chipcard reading and processing.
+app-office/gnucash:hbci - Enable HBCI support, for connecting to some internet banks
+app-office/gnucash:quotes - Enable Online Stock Quote retrieval
+app-office/gnucash:register2 - Use the new register (Experimental)
+app-office/gnumeric:libgda - Enable database support through gnome-extra/libgda.
+app-office/gnumeric:perl - Enable perl plugin loader.
+app-office/gnumeric:python - Enable python plugin loader.
+app-office/kexi:marble - Enable displaying of maps using kde-apps/marble
+app-office/kexi:mdb - Enable support for Microsoft Access database
+app-office/kexi:webkit - Enable web form designer widget using dev-qt/qtwebkit
+app-office/kmymoney:activities - Enable kde-frameworks/kactivities integration
+app-office/kmymoney:addressbook - Enable kde-apps/akonadi contact integration
+app-office/kmymoney:hbci - Enable HBCI support using net-libs/aqbanking
+app-office/kmymoney:holidays - Enable kde-apps/kholidays integration
+app-office/kmymoney:quotes - Enable Online Stock Quote retrieval
+app-office/kmymoney:weboob - Enable import of online banking transactions extracted by www-client/weboob
+app-office/kraft:pim - Enable support for KDE PIM resources integration
+app-office/libreoffice:coinmp - Use sci-libs/coinor-mp as alternative solver
+app-office/libreoffice:collada - Enable Collada for rendering 3D models stored in *.dae and *.kmz format
+app-office/libreoffice:gltf - Use media-libs/libgltf for inserting 3D models in the glTF format into presentations
+app-office/libreoffice:googledrive - Enable support for remote files on Google Drive
+app-office/libreoffice:gtk2 - Enable legacy gtk2 frontend
+app-office/libreoffice:gtk3 - Enable experimental gtk3 frontend
+app-office/libreoffice:jemalloc - Use dev-libs/jemalloc for allocations
+app-office/libreoffice:odk - Build the Office Development Kit
+app-office/libreoffice:pdfimport - Enable PDF import via the Poppler library
+app-office/libreoffice:quickstarter - Build the system tray quickstarter
+app-office/libreoffice:vlc - Use media-video/vlc for video embedding
+app-office/libreoffice-l10n:offlinehelp - Install help files locally instead of using the LibreOffice Wiki
+app-office/lyx:aspell - Add support for aspell spellchecking
+app-office/lyx:dia - Add support for diagrams (app-office/dia)
+app-office/lyx:docbook - Add support for docbook export
+app-office/lyx:dot - Add support for DOT import (media-gfx/graphviz)
+app-office/lyx:enchant - Add support for enchant spellchecking wrapper (both aspell and hunspell can be used by LyX).
+app-office/lyx:gnumeric - Add support for importing Gnumeric/OpenOffice/MS Excel spreadsheets into LyX.
+app-office/lyx:html - Add support for HTML import
+app-office/lyx:hunspell - Add support for spellchecking based on hunspell and reuse system-wide OpenOffice dictionaries. This also enable thesaurus dictionaries not accessible via aspell.
+app-office/lyx:monolithic-build - This should speed up compilation significantly when you have enough RAM (> 600 MB)
+app-office/lyx:rcs - Add support for revision control via dev-vcs/rcs
+app-office/lyx:rtf - Add support for RTF import/export packages
+app-office/magicpoint:contrib - Install additional contributed scripts
+app-office/orage:clock-panel-plugin - Build the clock plugin for the XFCE panel
+app-office/scribus:boost - Enable support for Boost based enhancement
+app-office/scribus:hunspell - Enable support for spell checking with app-text/hunspell
+app-office/scribus:minimal - Don't install headers (only required for e.g. plug-in developers)
+app-office/scribus:osg - 3D redering via dev-games/openscenegraph
+app-office/scribus:scripts - Install the scripts
+app-office/scribus:templates - Document tamplates
+app-office/scribus:tk - Install tk based scripts e.g. FontSample.py
+app-office/skrooge:activities - Enable kactivities support
+app-office/skrooge:designer - Build plugins for dev-qt/designer
+app-office/texmacs:netpbm - Add support for media-libs/netpbm
+app-office/texmacs:pdf - Add the experimental native pdf export
+app-office/texstudio:video - Use phonon for video embedding
+app-office/wps-office:sharedfonts - Install WPS fonts available system wide
+app-pda/barry:boost - Enable boost support
+app-pda/barry:desktop - Install the GUI desktop control panel
+app-pda/barry:gui - Install the GUI backup tool
+app-pda/gtkpod:clutter - Enable clutter support for displaying coverart
+app-portage/conf-update:colordiff - Use colors when displaying diffs (app-misc/colordiff)
+app-portage/conf-update:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+app-portage/eix:debug - Build with upstream's CXXFLAGS/LDFLAGS for debugging support; not recommended for normal use.
+app-portage/eix:doc - Create description of the eix cache file additionally in html format
+app-portage/eix:sqlite - Compile in support for portage's sqlite backend; to actually use it you need additional configuration of portage and eix
+app-portage/g-sorcery:bson - Support BSON file format for package DB
+app-portage/gemato:blake2 - Install dependencies needed for BLAKE2 hash functions
+app-portage/gemato:gpg - Install dependencies needed for OpenPGP signature verification support
+app-portage/gemato:sha3 - Install dependencies needed for SHA3 hash functions
+app-portage/grs:server - Install all the tools building systems
+app-portage/layman:bazaar - Support dev-vcs/bzr based overlays
+app-portage/layman:cvs - Support dev-vcs/cvs based overlays
+app-portage/layman:darcs - Support dev-vcs/darcs based overlays
+app-portage/layman:g-sorcery - Support app-portage/g-sorcery based overlays
+app-portage/layman:git - Support dev-vcs/git based overlays
+app-portage/layman:gpg - Support app-crypt/gnupg signed overlays lists and manifests
+app-portage/layman:mercurial - Support dev-vcs/mercurial based overlays
+app-portage/layman:squashfs - Support mounting squashfs image overlays locally read-only
+app-portage/layman:subversion - Support dev-vcs/subversion based overlays
+app-portage/layman:sync-plugin-portage - Install the sys-apps/portage sync module
+app-portage/pfl:network-cron - Adds a cron job which does a weekly submit of the package database
+app-portage/tatt:templates - Install template scripts to be used with tatt
+app-shells/autojump:ipython - Add support for dev-python/ipython
+app-shells/bash:bashlogger - Log ALL commands typed into bash; should ONLY be used in restricted environments such as honeypots
+app-shells/bash:mem-scramble - Build with custom malloc/free overwriting allocated/freed memory
+app-shells/bash:net - Enable /dev/tcp/host/port redirection
+app-shells/bash:plugins - Add support for loading builtins at runtime via 'enable'
+app-shells/dash:vanilla - Support echo -n, and enable echo -e all the time (unsupported)
+app-shells/mpv-bash-completion:luajit - Use dev-lang/luajit instead of dev-lang/lua
+app-shells/pdsh:rsh - This allows the use of rsh (remote shell) and rcp (remote copy) for authoring websites. sftp is a much more secure protocol and is preferred.
+app-shells/scsh-install-lib:scsh - Use a non-FHS directory layout
+app-shells/shish:diet - Use dev-libs/dietlibc
+app-text/asciidoc:highlight - Enable source code highlighting
+app-text/atril:caja - Enable property page extension in mate-base/caja
+app-text/atril:dvi - Enable build-in DVI viewer
+app-text/atril:epub - Enable build-in DVI viewer using net-libs/webkit-gtk
+app-text/atril:gtk3 - Build with GTK+3 instead of GTK+2
+app-text/atril:t1lib - Enable the Type-1 fonts for the build-in DVI viewer (media-libs/t1lib)
+app-text/atril:xps - Enable XPS viewer using app-text/libgxps
+app-text/blogc:git - Build blogc-git-receiver tool
+app-text/blogc:httpd - Build blogc-runserver tool
+app-text/blogc:make - Build blogc-make tool
+app-text/cb2bib:webengine - Use dev-qt/qtwebengine instead of dev-qt/qtwebkit
+app-text/coolreader:wxwidgets - Use x11-libs/wxGTK instead of Qt5
+app-text/crm114:mew - Add support for using the mewdecode mime decoder (app-emacs/mew)
+app-text/crm114:mimencode - Add support for using the mimencode mime (net-mail/metamail)
+app-text/crm114:normalizemime - Add support for using the normalizemime (mail-filter/normalizemime)
+app-text/dbacl:interactive - Enable the interactive mailinspect ability
+app-text/dblatex:inkscape - Use inkscape to convert SVG. Disable to use gnome-base/librsvg instead.
+app-text/dictd:judy - Build Judy-based (dev-libs/judy) plugin implementing fast "exact" and especially "lev" strategies
+app-text/dictd:minimal - Don't build server but dict client, dictzip and dictfmt only.
+app-text/docbook-sgml-utils:jadetex - Add support for app-text/jadetex (for processing tex files produced by the TeX backend of Jade)
+app-text/docbook-xsl-ns-stylesheets:ruby - Install the Ruby-based dbtoepub script; requires an interpreter compatible with app-eselect/eselect-ruby.
+app-text/docbook-xsl-stylesheets:ruby - Install the Ruby-based dbtoepub script; requires an interpreter compatible with app-eselect/eselect-ruby.
+app-text/ebook-tools:lit2epub - Install lit2epub script
+app-text/editorconfig-core-c:cli - Install command line interface.
+app-text/enchant:aspell - Adds support for app-text/aspell spell checker
+app-text/enchant:hunspell - Adds support for app-text/hunspell spell checker
+app-text/enchant:zemberek - Adds support for app-text/zemberek-server spell checker server
+app-text/evince:dvi - Enable the built-in DVI viewer
+app-text/evince:nautilus - Enable property page extension in gnome-base/nautilus
+app-text/evince:t1lib - Enable the Type-1 fonts for the built-in DVI viewer (media-libs/t1lib)
+app-text/evince:xps - Enable XPS viewer using app-text/libgxps
+app-text/getxbook:ocr - Use app-text/tesseract for optical character recognition
+app-text/ghostscript-gpl:unicode - Add support for unicode passwords via net-dns/libidn
+app-text/glark:zip - Support for ZIP files using dev-ruby/rubyzip
+app-text/groonga:abort - Enable query abortion
+app-text/groonga:benchmark - Build benchmark programs
+app-text/groonga:dynamic-malloc-change - Allow dynamic memory allocation change for testing
+app-text/groonga:exact-alloc-count - Atomic counting for memory alloc count
+app-text/groonga:fmalloc - Make memory allocation failed in specified condition for debug
+app-text/groonga:futex - Use futex
+app-text/groonga:libevent - Enable dev-libs/libevent used for suggestion
+app-text/groonga:mecab - Use app-text/mecab for morphological analysis
+app-text/groonga:msgpack - Enable dev-libs/msgpack used for suggestion
+app-text/groonga:nfkc - Use nfkc based utf8 normalization
+app-text/groonga:sphinx - Enable document generation by app-misc/sphinx
+app-text/groonga:uyield - Build for detecting race conditions
+app-text/groonga:zeromq - Enable net-libs/zeromq used for suggestion
+app-text/gtranslator:gnome-dictionary - Enable plugin for dictionary lookups using app-dicts/gnome-dictionary.
+app-text/gtranslator:gucharmap - Enable plugin for unicode symbols selection using gnome-extra/gucharmap.
+app-text/hyperestraier:mecab - Enable app-text/mecab support for Estraier
+app-text/kbibtex:webengine - Use dev-qt/qtwebengine for HTML previews
+app-text/kbibtex:webkit - Use dev-qt/qtwebkit for HTML previews
+app-text/kbibtex:zotero - Enable support for synchronisation with zotero.org web service
+app-text/lcdf-typetools:kpathsea - Enable integration with kpathsea search library (TeX related)
+app-text/libebook:tools - Build file conversion tools
+app-text/libmwaw:tools - Build file conversion tools
+app-text/libqxp:tools - Build file conversion tools
+app-text/libstaroffice:tools - Build conversion tools
+app-text/libstaroffice:zlib - Enable support for compressed data
+app-text/libwpd:tools - Build file conversion tools
+app-text/libwps:tools - Build file conversion tools
+app-text/mathtex:png - Generate png images by default instead of gif
+app-text/mupdf:openssl - Use dev-libs/openssl crypto backend
+app-text/pandoc:embed_data_files - Embed data files in binary for relocatable executable.
+app-text/pandoc:http-conduit - Enable downloading of resources over https.
+app-text/pandoc:https - Enable support for downloading of resources over https.
+app-text/pandoc:make-pandoc-man-pages - Build program to regenerate pandoc man pages from README.
+app-text/pandoc:network-uri - Get Network.URI from the network-uri package.
+app-text/pandoc:trypandoc - Build trypandoc cgi executable.
+app-text/pandoc:weigh-pandoc - Build weigh-pandoc to measure memory usage.
+app-text/pastebinit:crypt - Install pbputs for gpg-encrypted pastes
+app-text/pdfgrep:unac - Removing accents and ligatures before search
+app-text/pelican:markdown - Markdown support
+app-text/podofo:boost - Add support for boost
+app-text/podofo:tools - Build and install commandline tools.
+app-text/poppler:nss - Enable signatures handling with dev-libs/nss
+app-text/poppler:utils - Install command-line PDF converters and various utilities.
+app-text/qpdf:perl - Install fix-qdf tool (for reverting PDF edits) written in perl
+app-text/qpdfview:fitz - Use experimental fitz rendering, provided by app-text/mupdf, instead of poppler
+app-text/qpdfview:synctex - Add support for searching TeX sources
+app-text/sdcv:darkterm - Improve readability of color output on terminals with dark background.
+app-text/sgmltools-lite:jadetex - Add support for app-text/jadetex (for processing tex files produced by the TeX backend of Jade)
+app-text/stardict:advertisement - Enable stardict advertisements plugin
+app-text/stardict:cal - Enable calendar support using cal program
+app-text/stardict:dictdotcn - Enable dict.cn network plugin (for Chinese language)
+app-text/stardict:espeak - Enable text to speech synthesizer plugin using app-accessibility/espeak engine
+app-text/stardict:flite - Enable text to speech synthesizer plugin using app-accessibility/flite engine
+app-text/stardict:fortune - Enable plugin to read fortune messages using games-misc/fortune-mod. You may consider installing games-misc/fortune-mod-all to get all fortune messages.
+app-text/stardict:gucharmap - Enable plugin for unicode symbols description using gnome-extra/gucharmap
+app-text/stardict:htmlparse - Enable plugin to parse dictionaries with html content
+app-text/stardict:info - Enable plugin to read info pages
+app-text/stardict:man - Enable plugin to read manual pages
+app-text/stardict:powerwordparse - Enable plugin to parse powerword dictionaries
+app-text/stardict:pronounce - Install WyabdcRealPeopleTTS package (it is just many .wav files) to make StarDict pronounce English words
+app-text/stardict:qqwry - Enable QQWry plugin, which provides information (in Chinese language) about geographical positions, owner, etc. for IP addresses
+app-text/stardict:tools - Build and install dictionary management tools and converters from various dictionary formats
+app-text/stardict:updateinfo - Enable plugin to check for stardict updates
+app-text/stardict:wikiparse - Enable plugin to parse dictionaries in wikimedia format
+app-text/stardict:wordnet - Enable wordnet plugin to find similar English words using lexical database
+app-text/stardict:xdxfparse - Enable plugin to parse dictionaries in xdxf (XML Dictionary eXchange Format)
+app-text/stardict:youdaodict - Enable youdao.com network plugin (for Chinese language)
+app-text/sword:clucene - Use dev-cpp/clucene for lucene search support
+app-text/tesseract:math - Enable support for recognition of equations.
+app-text/tesseract:opencl - Enable opencl support for speedup using GPU computation.
+app-text/tesseract:osd - Enable support orientation and script detection.
+app-text/tesseract:scrollview - Install viewer to debug recognition (ScrollView).
+app-text/tesseract:training - Install training applications to add support for new languages.
+app-text/tesseract:webp - Enable support for webp image format.
+app-text/texlive:context - Add support for the ConTeXt format (dev-texlive/texlive-context)
+app-text/texlive:detex - Add support for dev-tex/detex, a filter program that removes the LaTeX (or TeX) control sequences
+app-text/texlive:dvi2tty - Add support for dev-tex/dvi2tty to preview dvi-files on text-only devices
+app-text/texlive:epspdf - Add support for app-text/epspdf, a tool for converting [e]ps files to pdf
+app-text/texlive:extra - Add support for extra TeXLive packages
+app-text/texlive:games - Add typesetting support for games (chess, etc.) (dev-texlive/texlive-games)
+app-text/texlive:graphics - Add support for several graphics packages (pgf, tikz,...)
+app-text/texlive:humanities - Add LaTeX support for the humanities (dev-texlive/texlive-humanities)
+app-text/texlive:jadetex - Add support for app-text/jadetex (for processing tex files produced by the TeX backend of Jade)
+app-text/texlive:luatex - Add extra support for luatex
+app-text/texlive:metapost - Add support for metapost: A tool for creating graphics in scalable PostScript
+app-text/texlive:music - Add support for music typesetting (dev-texlive/texlive-music)
+app-text/texlive:omega - Add omega packages (dev-texlive/texlive-omega)
+app-text/texlive:pdfannotextractor - Add dev-tex/pdfannotextractor support, for extracting annotations from PDF files
+app-text/texlive:pstricks - Add pstricks packages (dev-texlive/texlive-pstricks)
+app-text/texlive:publishers - Add support for publishers (dev-texlive/texlive-publishers)
+app-text/texlive:science - Add typesetting support for natural and computer sciences (dev-texlive/texlive-science)
+app-text/texlive:tex4ht - Add support for dev-tex/tex4ht (for converting (La)TeX to (X)HTML, XML and OO.org)
+app-text/texlive:texi2html - Add support for app-text/texi2html which converts texi files to HTML
+app-text/texlive:xetex - Add support for XeTeX macros (dev-texlive/texlive-xetex)
+app-text/texlive:xindy - Add support for app-text/xindy, a flexible indexing system
+app-text/texlive-core:luajittex - Add support for LuaJitTeX: LuaTeX based on LuaJIT which is usually faster.
+app-text/texlive-core:xetex - Add support for XeTeX: a TeX system with Unicode and modern font technologies.
+app-text/wdiff:experimental - Build experimental utilities (mdiff, unify, wdiff2)
+app-text/webgen:builder - Enable programmatic HTML/XML generation
+app-text/webgen:highlight - Enable syntax highlighting for certain plugins
+app-text/webgen:markdown - Markdown support
+app-text/wklej:vim - Install the vim plugin allowing to paste through ':Wklej'.
+app-text/writerperfect:abiword - Add support for abiword format using app-text/libabw
+app-text/writerperfect:ebook - Add support for various ebook formats using app-text/libebook
+app-text/writerperfect:freehand - Add support for freehand format using media-libs/libfreehand
+app-text/writerperfect:gsf - Add support for structured files using gnome-extra/libgsf
+app-text/writerperfect:keynote - Add support for keynote format using app-text/libetonyek
+app-text/writerperfect:mspub - Add support to mspub format using app-text/libmspub
+app-text/writerperfect:mwaw - Add support to mwaw formats using app-text/libmwaw
+app-text/writerperfect:pagemaker - Add support to pagemaker formats using media-libs/libpagemaker
+app-text/writerperfect:visio - Add support for visio format using media-libs/libvisio
+app-text/writerperfect:wpd - Add support for wpd format using app-text/libwpd
+app-text/writerperfect:wpg - Add support for wpg format using app-text/libwpg
+app-text/writerperfect:wps - Add support for wps format using app-text/libwps
+app-text/wv:tools - Install optional utilities considered deprecated in favor of using AbiWord.
+app-text/xmlto:text - Support conversion from XML to plain text
+app-text/zathura:magic - Use libmagic to determine mimetypes
+app-text/zathura:synctex - Use libsynctex to get latex codeline from pdf
+app-text/zathura-meta:cb - Install plug-in for ComicBook support
+app-vim/gentoo-syntax:ignore-glep31 - Remove GLEP 31 (UTF-8 file encodings) settings
+app-vim/vim-latex:html - Install HTML documentation
+app-vim/youcompleteme:clang - Enable semantic support for C-family languages using sys-devel/clang
+dev-ada/asis:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/asis:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/aunit:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/aunit:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/aws:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/aws:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gnat_util:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/gnat_util:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gnat_util:shared - Build gnat_util shared library
+dev-ada/gnat_util:static-pic - Build gnat_util static library with pic code
+dev-ada/gnatcoll:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/gnatcoll:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gnatcoll:projects - Adds support for projects
+dev-ada/gnatcoll:pygobject - Adds support for pygobject
+dev-ada/gnatcoll:shared - Build shared library
+dev-ada/gnatcoll:tools - Build associated tools
+dev-ada/gnatmem:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/gnatmem:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gprbuild:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/gprbuild:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gtkada:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/gtkada:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/gtkada:shared - Build gtkada as shared library
+dev-ada/libadalang:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/libadalang:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/libgpr:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/libgpr:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/libgpr:shared - Build shared library
+dev-ada/libgpr:static-pic - Build static library with pic code
+dev-ada/xmlada:gnat_2016 - Compile with dev-lang/gnat-gpl-2016
+dev-ada/xmlada:gnat_2017 - Compile with dev-lang/gnat-gpl-2017
+dev-ada/xmlada:shared - Build shared library
+dev-ada/xmlada:static-pic - Build static library with pic code
+dev-cpp/eigen:c++11 - Build using the C++11 standard
+dev-cpp/eigen:cuda - Build with cuda support
+dev-cpp/glog:gflags - Use dev-cpp/gflags for flag parsing
+dev-cpp/glog:unwind - Use sys-libs/libunwind for stack unwinding instead of glibc/gcc (may be more reliable on x86_64)
+dev-cpp/libcmis:man - Build and install man pages.
+dev-cpp/libjson-rpc-cpp:http-client - Build support for HTTP client using net-misc/curl
+dev-cpp/libjson-rpc-cpp:http-server - Build support for HTTP server using net-libs/libmicrohttpd
+dev-cpp/libjson-rpc-cpp:redis-client - Build support for Redis client using dev-libs/hiredis
+dev-cpp/libjson-rpc-cpp:redis-server - Build support for Redis server using dev-libs/hiredis
+dev-cpp/libjson-rpc-cpp:stubgen - Build header stub code generator (needed for development and when pregenerated headers are not bundled)
+dev-cpp/websocketpp:boost - Use dev-libs/boost instead of C++11
+dev-cpp/xsd:ace - Enable support for serializing to/from an ACE CDR stream
+dev-db/aerospike-server-community:tools - Install extra tools
+dev-db/cppdb:mysql_internal - Don't build a separate mysql loadable module but rather build it into the cppdb library itself
+dev-db/cppdb:odbc_internal - Don't build a separate postgresql loadable module but rather build it into the cppdb library itself
+dev-db/cppdb:postgres_internal - Don't build a separate odbc loadable module but rather build it into the cppdb library itself
+dev-db/cppdb:sqlite_internal - Don't build a separate sqlite3 loadable module but rather build it into the cppdb library itself
+dev-db/etcd:server - Installs etcd daemon
+dev-db/firebird:server - Install the server components of Firebird, not just the client
+dev-db/firebird:xinetd - Install ClassicServer
+dev-db/maatkit:udf - Build the MySQL UDFs shipped with maatkit, requires non-minimal MySQL
+dev-db/mariadb:backup - Build mariadb-backup which supports SST and hot backup of InnoDB, Aria and MyISAM including compression and encryption
+dev-db/mariadb:client-libs - Build the client libraries from the server package instead of the C Connector packages
+dev-db/mariadb:cluster - Add support for NDB clustering (deprecated)
+dev-db/mariadb:community - Enables the community features from upstream.
+dev-db/mariadb:embedded - Build embedded server (libmysqld)
+dev-db/mariadb:extraengine - Add support for alternative storage engines (Archive, CSV, Blackhole, Federated(X), Partition)
+dev-db/mariadb:galera - Enables galera replication
+dev-db/mariadb:innodb-lz4 - Enables lz4 compression methods for InnoDB/XtraDB
+dev-db/mariadb:innodb-lzo - Enables lzo compression methods for InnoDB/XtraDB
+dev-db/mariadb:innodb-snappy - Enables snappy compression methods for InnoDB/XtraDB using app-arch/snappy
+dev-db/mariadb:jdbc - Enable the CONNECT engine to access foreign databases via JDBC
+dev-db/mariadb:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/mariadb:latin1 - Use LATIN1 encoding instead of UTF8
+dev-db/mariadb:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+dev-db/mariadb:max-idx-128 - Raise the max index per table limit from 64 to 128
+dev-db/mariadb:minimal - Install client programs only, no server
+dev-db/mariadb:mroonga - Add support for the Mroonga engine for interfacing with the Groonga text search
+dev-db/mariadb:numa - Enable NUMA support using sys-process/numactl (NUMA kernel support is also required)
+dev-db/mariadb:openssl - Enable SSL connections and crypto functions using dev-libs/openssl
+dev-db/mariadb:oqgraph - Add support for the Open Query GRAPH engine
+dev-db/mariadb:pam - Enable the optional PAM authentication plugin for the server
+dev-db/mariadb:profiling - Add support for statement profiling (requires USE=community).
+dev-db/mariadb:rocksdb - Add support for RocksDB; a key/value, LSM database optimized for flash storage
+dev-db/mariadb:server - Build the server program
+dev-db/mariadb:sphinx - Add suport for the sphinx full-text search engine
+dev-db/mariadb:sst-mariabackup - Add tools needed to support the mariabackup SST method
+dev-db/mariadb:sst-rsync - Add tools needed to support the rsync SST method
+dev-db/mariadb:sst-xtrabackup - Add tools needed to support the xtrabackup and xtrabackup-v2 SST methods
+dev-db/mariadb:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-db/mariadb:test - Install upstream testsuites for end use.
+dev-db/mariadb:tokudb - Add support for TokuDB storage engine
+dev-db/mariadb:yassl - Enable SSL connections and crypto functions using the bundled yaSSL
+dev-db/mariadb-connector-c:mysqlcompat - Enable mysqlclient library symbolic links
+dev-db/mariadb-galera:embedded - Build embedded server (libmysqld)
+dev-db/mariadb-galera:extraengine - Add support for alternative storage engines (Archive, CSV, Blackhole, Federated(X), Partition)
+dev-db/mariadb-galera:jdbc - Enable the CONNECT engine to access foreign databases via JDBC
+dev-db/mariadb-galera:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/mariadb-galera:latin1 - Use LATIN1 encoding instead of UTF8
+dev-db/mariadb-galera:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+dev-db/mariadb-galera:openssl - Enable SSL connections and crypto functions using dev-libs/openssl
+dev-db/mariadb-galera:oqgraph - Add support for the Open Query GRAPH engine
+dev-db/mariadb-galera:profiling - Add support for statement profiling (requires USE=community).
+dev-db/mariadb-galera:server - Build the server program
+dev-db/mariadb-galera:sphinx - Add suport for the sphinx full-text search engine
+dev-db/mariadb-galera:sst-rsync - Add tools needed to support the rsync SST method
+dev-db/mariadb-galera:sst-xtrabackup - Add tools needed to support the xtrabackup and xtrabackup-v2 SST methods
+dev-db/mariadb-galera:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-db/mariadb-galera:test - Install upstream testsuites for end use.
+dev-db/mariadb-galera:tokudb - Add support for TokuDB storage engine
+dev-db/mariadb-galera:yassl - Enable SSL connections and crypto functions using the bundled yaSSL
+dev-db/maxscale:jemalloc - Use dev-libs/jemalloc for allocations
+dev-db/maxscale:rabbitmq - Add support for RabbitMQ message queue
+dev-db/mongodb:mms-agent - Install the MongoDB Monitoring Service agent
+dev-db/mongodb:tools - Install the MongoDB tools (mongoimport, mongodump...) from app-admin/mongo-tools
+dev-db/mysql:cluster - Add support for NDB clustering (deprecated)
+dev-db/mysql:community - Enables the community features from upstream.
+dev-db/mysql:embedded - Build embedded server (libmysqld)
+dev-db/mysql:extraengine - Add support for alternative storage engines (Archive, CSV, Blackhole, Federated(X), Partition)
+dev-db/mysql:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/mysql:latin1 - Use LATIN1 encoding instead of UTF8
+dev-db/mysql:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+dev-db/mysql:max-idx-128 - Raise the max index per table limit from 64 to 128
+dev-db/mysql:minimal - Install client programs only, no server
+dev-db/mysql:numa - Enable NUMA support using sys-process/numactl (NUMA kernel support is also required)
+dev-db/mysql:openssl - Enable SSL connections and crypto functions using dev-libs/openssl
+dev-db/mysql:profiling - Add support for statement profiling (requires USE=community).
+dev-db/mysql:server - Build the server program
+dev-db/mysql:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-db/mysql:test - Install upstream testsuites for end use.
+dev-db/mysql:yassl - Enable SSL connections and crypto functions using the bundled yaSSL
+dev-db/mysql-cluster:cluster - Add support for NDB clustering
+dev-db/mysql-cluster:community - Enables the community features from upstream.
+dev-db/mysql-cluster:embedded - Build embedded server (libmysqld)
+dev-db/mysql-cluster:extraengine - Add support for alternative storage engines (Archive, CSV, Blackhole, Federated(X), Partition)
+dev-db/mysql-cluster:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/mysql-cluster:latin1 - Use LATIN1 encoding instead of UTF8
+dev-db/mysql-cluster:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+dev-db/mysql-cluster:max-idx-128 - Raise the max index per table limit from 64 to 128
+dev-db/mysql-cluster:minimal - Install client programs only, no server
+dev-db/mysql-cluster:numa - Enable NUMA support using sys-process/numactl (NUMA kernel support is also required)
+dev-db/mysql-cluster:openssl - Enable SSL connections and crypto functions using dev-libs/openssl
+dev-db/mysql-cluster:profiling - Add support for statement profiling (requires USE=community).
+dev-db/mysql-cluster:server - Build the server program
+dev-db/mysql-cluster:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-db/mysql-cluster:test - Install upstream testsuites for end use.
+dev-db/mysql-cluster:yassl - Enable SSL connections and crypto functions using the bundled yaSSL
+dev-db/mysql-connector-c++:gcov - Build coverage support
+dev-db/oracle-instantclient:jdbc - Support for XA, Internationalization, and RowSet operations under JDBC
+dev-db/oracle-instantclient:odbc - Libraries for enabling ODBC applications
+dev-db/oracle-instantclient:sdk - Header files and an example makefile for developing Oracle applications
+dev-db/oracle-instantclient:sqlplus - Libraries and executable for running SQL*Plus
+dev-db/oracle-instantclient:tools - Workload Replay Client
+dev-db/percona-server:embedded - Build embedded server (libmysqld)
+dev-db/percona-server:extraengine - Add support for alternative storage engines (Archive, CSV, Blackhole, Federated(X), Partition)
+dev-db/percona-server:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/percona-server:latin1 - Use LATIN1 encoding instead of UTF8
+dev-db/percona-server:libressl - Enable SSL connections and crypto functions using dev-libs/libressl
+dev-db/percona-server:numa - Enable NUMA support using sys-process/numactl (NUMA kernel support is also required)
+dev-db/percona-server:openssl - Enable SSL connections and crypto functions using dev-libs/openssl
+dev-db/percona-server:profiling - Add support for statement profiling (requires USE=community).
+dev-db/percona-server:server - Build the server program
+dev-db/percona-server:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-db/percona-server:test - Install upstream testsuites for end use.
+dev-db/percona-server:tokudb - Add support for TokuDB storage engine
+dev-db/percona-server:tokudb-backup-plugin - Builds the TokuDB backup plugin
+dev-db/percona-server:yassl - Enable SSL connections and crypto functions using the bundled yaSSL
+dev-db/pgadmin3:databasedesigner - Enable the Database Designer component
+dev-db/pgbouncer:c-ares - Use c-ares as the DNS backend instead of evdns (libevent).
+dev-db/pgbouncer:udns - Use udns as the DNS backend instead of evdns (libevent). Supports IPv4 only.
+dev-db/pgpool2:memcached - Use memcached for query caching.
+dev-db/pgrouting:drivingdistance - Enable to calculate driving distance
+dev-db/pgrouting:html - Install HTML formatted documentation
+dev-db/phpmyadmin:setup - Installs the phpMyAdmin setup utility. Users who don't use the utility should disable this USE flag for security reasons as the setup tool was the target of various exploits in the past.
+dev-db/postgis:address-standardizer - Normalize US and CA postal addresses
+dev-db/postgis:gtk - Build graphical interface for shp2pgsql (shp2pgsql-gui)
+dev-db/postgis:mapbox - Add capability to transform geometry into Mapbox Vector Tile
+dev-db/postgis:topology - Build topology spatial types and functions
+dev-db/postgresql:pg_legacytimestamp - Use double precision floating-point numbers instead of 64-bit integers for timestamp storage.
+dev-db/postgresql:server - Disable to build and install the clients and libraries only.
+dev-db/postgresql:uuid - Enable server side UUID generation (via dev-libs/ossp-uuid).
+dev-db/psqlodbc:iodbc - Use dev-db/libiodbc. Disable to use dev-db/unixODBC.
+dev-db/redis:jemalloc - Use dev-libs/jemalloc for allocations.
+dev-db/redis:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-db/redis:tcmalloc - Use tcmalloc from dev-util/google-perftools for allocations.
+dev-db/rethinkdb:jemalloc - Use dev-libs/jemalloc for allocations (default).
+dev-db/rethinkdb:tcmalloc - Use tcmalloc from dev-util/google-perftools for allocations.
+dev-db/soci:boost - Enable boost support
+dev-db/soci:empty - Build the sample backend called Empty
+dev-db/spatialite:geos - Add the sci-libs/geos library for exact topological tests
+dev-db/spatialite:proj - Add the sci-libs/proj library for reprojection features
+dev-db/spatialite:xls - Add the dev-libs/freexl library for xls import support
+dev-db/sqlite:secure-delete - Enable overwriting of deleted content with zeros by default (http://sqlite.org/pragma.html#pragma_secure_delete), causing some performance penalty
+dev-db/sqlite:tools - Install additional tools
+dev-db/sqlitestudio:cli - Build CLI interface
+dev-db/tokumx:pax_kernel - Apply patch needed for hardened kernels
+dev-db/unixODBC:minimal - Disable bundled drivers and extra libraries (most users don't need these)
+dev-db/unixODBC:odbcmanual - Administrator, Internal Structure, Programmer and User documentation
+dev-embedded/avrdude:ftdi - Enable support for USB FTDI chips via dev-embedded/libftdi
+dev-embedded/libftdi:tools - build ftdi_eeprom helper tool
+dev-embedded/openocd:cmsis-dap - Support for CMSIS-DAP compliant adapters
+dev-embedded/openocd:dummy - Build the dummy port driver
+dev-embedded/openocd:ftdi - Enable support for USB FTDI chips via dev-embedded/libftdi
+dev-embedded/openocd:jlink - Build the SEGGER J-Link driver
+dev-embedded/openocd:parport - Enable support for parport JTAG devices
+dev-embedded/openocd:verbose-io - Verbose IO and comm JTAG and USB messages
+dev-embedded/sdcc:boehm-gc - Enable Hans Boehm's garbage collector dev-libs/boehm-gc
+dev-embedded/sdcc:device-lib - Enable built of devices libraries
+dev-embedded/sdcc:ds390 - Add support for Dallas DS390
+dev-embedded/sdcc:ds400 - Add support for Dallas DS400
+dev-embedded/sdcc:gbz80 - Add support for Gameboy gbz80
+dev-embedded/sdcc:hc08 - Add support for Freescale/Motorola HC08 based
+dev-embedded/sdcc:mcs51 - Add support for Intel mcs51
+dev-embedded/sdcc:non-free - Enable non-free runtime library parts
+dev-embedded/sdcc:packihx - Enable Intel HEX files pack utility
+dev-embedded/sdcc:pic14 - Add support for Microchip 14 bits PICs
+dev-embedded/sdcc:pic16 - Add support for Microchip 16 bits PICs
+dev-embedded/sdcc:r2k - Add support for Rabbit 2000
+dev-embedded/sdcc:r3ka - Add support for Rabbit 3000A
+dev-embedded/sdcc:s08 - Add support for Freescale/Motorola S08
+dev-embedded/sdcc:sdbinutils - Enable SDCC library archive utilities sdar, sdranlib, sdnm
+dev-embedded/sdcc:sdcdb - Enable SDCC source level debugger
+dev-embedded/sdcc:sdcpp - Enable SDCC preprocessor based on GCC cpp
+dev-embedded/sdcc:stm8 - Add support for STMicroelectronics STM8
+dev-embedded/sdcc:tlcs90 - Add support for TLCS-90
+dev-embedded/sdcc:ucsim - Enable software simulator for microcontrollers
+dev-embedded/sdcc:z180 - Add support for Zilog Z180
+dev-embedded/sdcc:z80 - Add support for Zilog Z80
+dev-embedded/urjtag:ftd2xx - Enable support for USB FTDI chips via dev-embedded/libftd2xx
+dev-embedded/urjtag:ftdi - Enable support for USB FTDI chips via dev-embedded/libftdi
+dev-games/aseprite:bundled-libs - Use the upstream provided bundled version of allegro 4.4.2
+dev-games/aseprite:gtk3 - Enable support for the experimental native GTK File Dialog
+dev-games/aseprite:webp - Enable webp image format support
+dev-games/cegui:devil - Build the DevIL based ImageCodec module
+dev-games/cegui:freeimage - Build the FreeImage based ImageCodec module
+dev-games/cegui:irrlicht - Enable the Irrlicht renderer
+dev-games/cegui:ogre - Enable the OGRE renderer
+dev-games/cegui:tinyxml - Enable the Tiny XML parser module
+dev-games/cegui:xerces-c - Enable the Xerces-C++ XML parser module
+dev-games/cegui:zip - Enable the Minizip resource provider
+dev-games/crystalspace:3ds - Enables support for .3DS files in CrystalSpace
+dev-games/crystalspace:bullet - include support for Bullet library
+dev-games/crystalspace:cal3d - include support for skeleton animation
+dev-games/crystalspace:cegui - include support for Crazy Eddie GUI
+dev-games/crystalspace:cg - NVIDIA toolkit plugin
+dev-games/crystalspace:ode - include support for Open Dynamics Engine
+dev-games/guichan:allegro - Build the Allegro frontend
+dev-games/mygui:l10n_ru - Install some additional russian docs if 'doc' useflag enabled
+dev-games/mygui:ogre - Use the ogre render subsystem. (cannot combine with opengl)
+dev-games/mygui:opengl - Use the opengl render subsystem. (cannot combine with ogre)
+dev-games/mygui:plugins - Build MyGUI plugins
+dev-games/mygui:samples - Install MyGUI demos (needs ogre USE flag)
+dev-games/mygui:tools - Build the tools for development
+dev-games/ode:double-precision - more precise calculations at the expense of speed
+dev-games/ode:gyroscopic - enable gyroscopic term (may cause instability)
+dev-games/ogre:boost - enable boost support
+dev-games/ogre:cg - NVIDIA toolkit plugin
+dev-games/ogre:double-precision - more precise calculations at the expense of speed
+dev-games/ogre:freeimage - support images via freeimage
+dev-games/ogre:gl3plus - Build OpenGL 3+ RenderSystem (EXPERIMENTAL)
+dev-games/ogre:gles2 - build OpenGL ES 2.x RenderSystem
+dev-games/ogre:gles3 - Enable OpenGL ES 3.x Features
+dev-games/ogre:ois - pull in Object-oriented Input System library for samples
+dev-games/ogre:poco - when USE=threads, use poco for threading
+dev-games/ogre:tbb - when USE=threads, use tbb for threading
+dev-games/ogre:tools - build+install helper tools
+dev-games/ogre:zip - support zip archives
+dev-games/openscenegraph:asio - Enable support for dev-cpp/asio library
+dev-games/openscenegraph:fox - Build examples using x11-libs/fox library
+dev-games/openscenegraph:gdal - Enable support for sci-libs/gdal library
+dev-games/openscenegraph:las - Enable support for geospatial data LAS LiDAR format using sci-geosciences/liblas
+dev-games/openscenegraph:openinventor - Build OpenInventor plugin
+dev-games/openscenegraph:osgapps - Build osg applications
+dev-games/openscenegraph:sdl2 - Use media-libs/libsdl2 additionally to media-libs/libsdl
+dev-games/openscenegraph:xrandr - Enable support for the X xrandr extension
+dev-games/physfs:grp - Enable Build Engine GRP archive support
+dev-games/physfs:hog - Enable Descent I/II HOG archive support
+dev-games/physfs:mvl - Enable Descent I/II MVL archive support
+dev-games/physfs:qpak - Enable Quake I/II QPAK archive support
+dev-games/physfs:wad - Enable Doom WAD archive support
+dev-games/physfs:zip - Enable ZIP archive support
+dev-games/simgear:dns - Enable DNS resolver via net-libs/udns
+dev-games/simgear:gdal - Enable alternative terrain engine based on pagedLOD via sci-libs/gdal
+dev-games/simgear:subversion - Enable terrasync scenery downloader
+dev-haskell/abstract-deque:usecas - Enable the reference implementation to use hardware compare-and-swap.
+dev-haskell/aeson-pretty:lib-only - don't build 'aeson-pretty' executable.
+dev-haskell/ansi-terminal:example - Build the example application.
+dev-haskell/ansi-wl-pprint:example - Build the example application.
+dev-haskell/authenticate:network-uri - Get Network.URI from the network-uri package
+dev-haskell/bifunctors:semigroups - You can disable the use of the `semigroups` package using `-f-semigroups`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/bifunctors:tagged - You can disable the use of the `tagged` package using `-f-tagged`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/biosff:fclip - Build the fclip executable.
+dev-haskell/biosff:flower - Build the flower executable.
+dev-haskell/biosff:frecover - Build the frecover executable.
+dev-haskell/blaze-builder-enumerator:newbuilder - use bytestring-builder instead of blaze-builder-0.3
+dev-haskell/bytedump:executable - build executable file
+dev-haskell/bytes:test-doctests - Enable the doctest suite when using the enable-tests option for cabal.
+dev-haskell/c2hs:regression - run regression tests
+dev-haskell/cabal-install:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/cabal-install:noprefs - Ignore 'preferred-versions' file from hackage's tarball.
+dev-haskell/certificate:executable - Build the executable
+dev-haskell/cgi:extensible-exceptions-in-base - Required to be enabled for >=dev-lang/ghc-7.
+dev-haskell/cgi:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/chell:color-output - use colors in program output
+dev-haskell/citeproc-hs:bibutils - use Chris Putnam's app-text/bibutils
+dev-haskell/citeproc-hs:embed_data_files - Embed locale files into the library (needed for windows packaging)
+dev-haskell/citeproc-hs:hexpat - use dev-haskell/hexpat instead of dev-haskell/xml for XML parsing
+dev-haskell/citeproc-hs:network - use dev-haskell/network and dev-haskell/http to retrieve CSL file from URIs
+dev-haskell/citeproc-hs:small_base - Choose the new smaller, split-up base package.
+dev-haskell/citeproc-hs:unicode_collation - Use Haskell bindings to the dev-libs/icu
+dev-haskell/cmark:system-cmark - use app-text/cmark instead of bundled copy
+dev-haskell/cmdargs:quotation - Build quote module
+dev-haskell/cmdargs:testprog - Build the test program
+dev-haskell/comonad:containers - You can disable the use of the `containers` package using `-f-containers`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/comonad:contravariant - You can disable the use of the `contravariant` package using `-f-contravariant`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If disabled we will not supply instances of `Contravariant`
+dev-haskell/comonad:distributive - You can disable the use of the `distributive` package using `-f-distributive`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If disabled we will not supply instances of `Distributive`
+dev-haskell/comonad:test-doctests - Run the doctests test suite
+dev-haskell/conduit:nohandles - experimental code to use raw system calls in place of handles. Not recommended for general use
+dev-haskell/configfile:buildtests - Build the executable to run unit tests.
+dev-haskell/contravariant:safe - Get Safe guarantees rather than merely Trustworthy, but with worse constant factors.
+dev-haskell/contravariant:semigroups - You can disable the use of the `semigroups` package using `-f-semigroups`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/contravariant:statevar - You can disable the use of the `StateVar` package using `-f-StateVar`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/contravariant:tagged - You can disable the use of the `tagged` package on older versons of GHC using `-f-tagged`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/cpu:executable - build 'cpuid' tool
+dev-haskell/crypto-api:all_cpolys - Build all the CMAC polynomes up to 10000 bits instead of just the usual ones
+dev-haskell/crypto-conduit:conduit11 - Use conduit >= 1.1.
+dev-haskell/cryptohash:cryptoapi - Defines crypto-api instances
+dev-haskell/cryptonite:integer-gmp - Whether or not to use GMP for some functions
+dev-haskell/cryptonite:support_aesni - allow compilation with AESNI on system and architecture that supports it
+dev-haskell/cryptonite:support_blake2_sse - Use SSE optimized version of BLAKE2
+dev-haskell/cryptonite:support_deepseq - add deepseq instances for cryptographic types
+dev-haskell/cryptonite:support_pclmuldq - Allow compilation with pclmuldq on architecture that supports it
+dev-haskell/cryptonite:support_rdrand - allow compilation with AESNI on system and architecture that supports it
+dev-haskell/dav:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/distributive:lib-werror - Compile with the ghc -Werror option
+dev-haskell/encoding:systemencoding - Provide the getSystemEncoding action to query the locale.
+dev-haskell/entropy:halvm - Build for the HaLVM.
+dev-haskell/filestore:maxcount - Make use of a recent (>= 2.3.0) Darcs feature which vastly improves the performance of 'latest'. You should disable this flag if you plan to use gitit with an older version of Darcs, or 'latest' will raise an error.
+dev-haskell/glib:closure_signals - Use the the GClosure-based signals implementation.
+dev-haskell/gtk:deprecated - Include definitions in this library that are considered obsolete.
+dev-haskell/gtk:fmode-binary - Set the default file translation mode for file I/O operations to _O_BINARY.
+dev-haskell/gtk:gio - Depend on GIO package, thereby enabling certain features.
+dev-haskell/gtk2hs-buildtools:closuresignals - Use the the GClosure-based signals implementation.
+dev-haskell/gtk3:fmode-binary - Set the default file translation mode for file I/O operations to _O_BINARY.
+dev-haskell/gtk3:gio - Depend on GIO package, thereby enabling certain features.
+dev-haskell/hackage-security:use-network-uri - Get Network.URI from the network-uri package.
+dev-haskell/happstack-server:network-uri - Get Network.URI from the network-uri package
+dev-haskell/happstack-server:template_haskell - Description: Template Haskell is available on this system
+dev-haskell/hashed-storage:diff - Provide the Storage.Hashed.Diff module.
+dev-haskell/hashed-storage:hpc - Compile with the profiling ghc flag -fhpc.
+dev-haskell/hashtables:bounds-checking - if on, use bounds-checking array accesses
+dev-haskell/hashtables:portable - if on, use only pure Haskell code and no GHC extensions.
+dev-haskell/hashtables:unsafe-tricks - turn on unsafe GHC tricks
+dev-haskell/haskeline:legacy-encoding - Use legacy iconv encoding for POSIX. This is only intended for testing.
+dev-haskell/haskeline:libiconv - Explicitly link against the libiconv library.
+dev-haskell/haskeline:terminfo - Use the terminfo package for POSIX consoles.
+dev-haskell/hdbc-odbc:buildstresstest - Build stress test
+dev-haskell/hdbc-sqlite3:buildtests - Build the executable to run unit tests
+dev-haskell/hdbc-sqlite3:splitbase - Choose the new smaller, split-up package.
+dev-haskell/hexpat:bundled-expat - Use bundled expat instead of dev-libs/expat
+dev-haskell/highlighting-kate:executable - Build the Highlight executable.
+dev-haskell/highlighting-kate:pcre-light - Use the pcre-light library instead of regex-pcre-builtin.
+dev-haskell/hit:executable - Build the executable
+dev-haskell/hlint:gpl - Use GPL libraries, specifically hscolour.
+dev-haskell/hps:build-exec - Build the `hps-fractals' executable
+dev-haskell/hs3:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/hslogger:buildtests - Build the executable to run unit tests.
+dev-haskell/hslua:apicheck - Compile Lua with -DLUA_USE_APICHECK..
+dev-haskell/hslua:system-lua - Use the system-wide lua instead of the bundled copy.
+dev-haskell/hsopenssl:fast-bignum - Enable fast moving of bignums between OpenSSL and GMP (GHC Only)
+dev-haskell/http:conduit10 - Use version 1.0.x or below of the conduit package (for the test suite).
+dev-haskell/http:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/http-api-data:use-text-show - Use text-show library for efficient ToHttpApiData implementations
+dev-haskell/http-client:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/http-streams:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/httpd-shed:buildexamples - Build example executables.
+dev-haskell/httpd-shed:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/hxt:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/icalendar:network-uri - use network-uri package
+dev-haskell/json:generic - Add support for generic encoder (dev-haskell/syb)
+dev-haskell/json:mapdict - Encode Haskell maps as JSON dicts
+dev-haskell/json:parsec - Add support for parsing with Parsec
+dev-haskell/json:pretty - Add support for using pretty printing combinators
+dev-haskell/language-dot:executable - Build the `ppdot' executable
+dev-haskell/lens:benchmark-uniplate - Enable benchmarking against Neil Mitchell's uniplate library for comparative performance analysis. Defaults to being turned off to avoid the extra dependency.
+dev-haskell/lens:dump-splices - Build and run the doctests test-suite.
+dev-haskell/lens:inlining - Generate inline pragmas when using template-haskell. This defaults to enabled, but you can to shut it off to benchmark the relative performance impact, or as last ditch effort to address compile errors resulting from the myriad versions of template-haskell that all purport to be 2.8.
+dev-haskell/lens:j - Attempt a parallel build with GHC 7.8.
+dev-haskell/lens:lib-werror - Turn on ghc-options: -Werror
+dev-haskell/lens:old-inline-pragmas - Some 7.6.1-rc1 users report their TH still uses old style inline pragmas. This lets them turn on inlining.
+dev-haskell/lens:safe - Disallow unsafeCoerce
+dev-haskell/lens:test-doctests - Build and run the doctests test-suite.
+dev-haskell/lens:test-hlint - You can disable the hlint test suite with -f-test-hlint
+dev-haskell/lens:test-hunit - You can disable the hunit test suite with -f-test-hunit
+dev-haskell/lens:test-properties - Build the properties test if we're building tests
+dev-haskell/lens:test-templates - Build the test templates if we're building tests
+dev-haskell/lens:trustworthy - Assert that we are trustworthy when we can
+dev-haskell/lifted-async:monad-control-1 - Use moand-control == 1.*
+dev-haskell/linear:template-haskell - You can disable the use of the `template-haskell` package using `-f-template-haskell`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/monad-control:instancest - If enabled this package will export MonadBaseControl instances for the lazy and strict ST monad. If disabled these instances are only exported when base >= 4.4. If enabled it is required that the transformer-base package exports MonadBase instances for ST. It will do this by default.
+dev-haskell/monad-logger:template_haskell - Enable Template Haskell support.
+dev-haskell/monad-par:chaselev - Use Chase-Lev Deques for higher-perf work-stealing.
+dev-haskell/nats:hashable - You can disable the use of the `hashable` package using USE=-hashable. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If set we will not supply an instance of `Hashable`.
+dev-haskell/network-data:small_base - Build the split-up base package.
+dev-haskell/pandoc-citeproc:bibutils - use Chris Putnam's app-text/bibutils
+dev-haskell/pandoc-citeproc:embed_data_files - Embed locale files into the library (needed for windows packaging)
+dev-haskell/pandoc-citeproc:hexpat - use dev-haskell/hexpat instead of dev-haskell/xml for XML parsing
+dev-haskell/pandoc-citeproc:network - use dev-haskell/network and dev-haskell/http to retrieve CSL file from URIs
+dev-haskell/pandoc-citeproc:small_base - Choose the new smaller, split-up base package.
+dev-haskell/pandoc-citeproc:test_citeproc - Build the test-citeproc program
+dev-haskell/pandoc-citeproc:unicode_collation - Use Haskell bindings to the dev-libs/icu
+dev-haskell/persistent:nooverlap - Use OverlappingInstances only for String. Only developers should use this.
+dev-haskell/persistent-sqlite:build-sanity-exe - Build a sanity check test executable.
+dev-haskell/pointed:comonad - optional instances
+dev-haskell/pointed:containers - optional instances
+dev-haskell/pointed:kan-extensions - optional instances
+dev-haskell/pointed:semigroupoids - optional instances
+dev-haskell/pointed:semigroups - optional instances
+dev-haskell/pointed:stm - optional instances
+dev-haskell/pointed:tagged - optional instances
+dev-haskell/pointed:transformers - optional instances
+dev-haskell/pointed:unordered-containers - optional instances
+dev-haskell/publicsuffixlist:create - export Network.PublicSuffixList.Create module
+dev-haskell/publicsuffixlist:runtimelist - read suffix list from dist at startup instead of embedding list into library
+dev-haskell/quickcheck:template_haskell - Enable additional test modules requiring Template Haskell support.
+dev-haskell/recaptcha:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/reflection:template-haskell - Enable template haskell.
+dev-haskell/rfc5051:mkunicodedata - build codes generator itself
+dev-haskell/sandi:with-conduit - Build with conduit
+dev-haskell/scientific:bytestring-builder - Provide the Data.ByteString.Builder.Scientific module (requires bytestring >= 0.10).
+dev-haskell/semigroupoid-extras:profunctors - You can disable the use of the `profunctors` package using `-f-profunctors`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroupoids:comonad - You can disable the use of the `comonad` package using `-f-comonad`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If disabled we will not supply instances of `Comonad`
+dev-haskell/semigroupoids:containers - You can disable the use of the `containers` package using `-f-containers`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroupoids:contravariant - You can disable the use of the `contravariant` package using `-f-contravariant`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If disabled we will not supply instances of `Contravariant`
+dev-haskell/semigroupoids:distributive - You can disable the use of the `distributive` package using `-f-distributive`. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If disabled we will not supply instances of `Distributive`
+dev-haskell/semigroupoids:tagged - You can disable the use of the `tagged` package using `-f-tagged`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroups:binary - provide instances for binary package
+dev-haskell/semigroups:bytestring - You can disable the use of the `bytestring` package using USE=-bytestring. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroups:containers - You can disable the use of the `containers` package using USE=-containers. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroups:deepseq - You can disable the use of the `deepseq` package using `-f-deepseq`. Disabing this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroups:hashable - You can disable the use of the `hashable` package using USE=-hashable. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users. If set we will not supply an instance of `Hashable`.
+dev-haskell/semigroups:text - You can disable the use of the `text` package using USE=-text. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/semigroups:transformers - provide instances for transformers package.
+dev-haskell/semigroups:unordered-containers - You can disable the use of the `unordered-containers` package using USE=-unordered-containers. Disabling this is an unsupported configuration, but it may be useful for accelerating builds in sandboxes for expert users.
+dev-haskell/sendfile:portable - Explicitly enable portable sendfile support (implemented in Haskell)
+dev-haskell/sha:exe - Build a sha1 and a sha384 executable similar to 'md5sum'.
+dev-haskell/shakespeare:test_coffee - Render tests through coffeescript render function.
+dev-haskell/shakespeare:test_export - Test export.
+dev-haskell/shakespeare:test_roy - Render tests through roy render function.
+dev-haskell/shakespeare-js:test_coffee - Test coffee.
+dev-haskell/shakespeare-js:test_export - Test export.
+dev-haskell/shakespeare-js:test_roy - Test roy.
+dev-haskell/shelly:lifted - run the tests against Shelly.Lifted
+dev-haskell/shuffle:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/simple-sendfile:allow-bsd - Allow use of BSD sendfile (disable on GNU/kFreeBSD)
+dev-haskell/skein:big-endian - When manually selecting the endianness, use big-endian (default is little-endian)
+dev-haskell/skein:force-endianness - Use a manually selected endian when compiling (see flag 'big-endian')
+dev-haskell/skein:reference - Use the reference implementation instead of the optimized one
+dev-haskell/skylighting:executable - Build the skylighting executable.
+dev-haskell/snap-core:portable - No non-haskell unportable code.
+dev-haskell/snap-server:build-pong - Build a server that just returns "PONG"
+dev-haskell/snap-server:openssl - enable https support using dev-haskell/hsopenssl
+dev-haskell/snap-server:portable - no non-haskell unportable code.
+dev-haskell/tagsoup:download - Build with Download module.
+dev-haskell/tagsoup:testprog - Build the test program.
+dev-haskell/tasty:colors - Enable colorful output
+dev-haskell/tasty-quickcheck:old-quickcheck - Use Quick-Check < 2.7.
+dev-haskell/texmath:executable - Compile test executable.
+dev-haskell/texmath:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/text:developer - operate in developer mode
+dev-haskell/thyme:bug-for-bug - bug-for-bug compatibility with time
+dev-haskell/thyme:lens - use the full lens package
+dev-haskell/thyme:show-internal - instance Show of internal representation
+dev-haskell/tls:compat - Accept SSLv2 compatible handshake.
+dev-haskell/tls:network - Use the base network library.
+dev-haskell/transformers-base:orphaninstances - Build instances for orphan datatypes.
+dev-haskell/transformers-compat:three - Use transformers-0.3
+dev-haskell/unix-compat:old-time - build against old-time package
+dev-haskell/uuagc:bootstrap_external - Use an external uuagc executable for bootstrapping.
+dev-haskell/uuagc:with-loag - Use dev-haskell/minisat external SAT-solver to schedule all Linear Ordered AGs.
+dev-haskell/vector:boundschecks - Enable bounds checking
+dev-haskell/vector:internalchecks - Enable internal consistency checks at the cost of a significant performance penalty
+dev-haskell/vector:unsafechecks - Enable bounds checking in unsafe operations at the cost of a significant performance penalty
+dev-haskell/vector-algorithms:bench - Build a benchmarking program.
+dev-haskell/vector-algorithms:boundschecks - Enable bounds checking.
+dev-haskell/vector-algorithms:internalchecks - Enable internal consistency checks at the cost of a significant performance penalty.
+dev-haskell/vector-algorithms:properties - Enable quickcheck tests.
+dev-haskell/vector-algorithms:unsafechecks - Enable bounds checking in unsafe operations at the cost of a significant performance penalty.
+dev-haskell/void:safe - dissable effective but unsafe coersions
+dev-haskell/wai-app-static:print - print debug info.
+dev-haskell/warp:allow-sendfilefd - Allow use of sendfileFd (not available on GNU/kFreeBSD).
+dev-haskell/warp:warp-debug - Add additional debuging information
+dev-haskell/x11:screensaver - whether to build XScreenSaver.
+dev-haskell/x509-store:executable - Build the executable
+dev-haskell/xss-sanitize:network-uri - Get Network.URI from the network-uri package.
+dev-haskell/yaml:no-examples - don't build the examples
+dev-haskell/yaml:no-exe - don't install the yaml2json executable
+dev-haskell/yaml:no-unicode - Don't enable unicode output. Instead, unicode characters will be escaped.
+dev-haskell/yaml:system-libyaml - Use system libyaml instead on generic one
+dev-haskell/yesod-auth:network-uri - Get Network.URI from the network-uri package
+dev-haskell/yesod-form:network-uri - Get Network.URI from the network-uri package
+dev-haskell/zip-archive:executable - Build the Zip executable.
+dev-haskell/zlib:non-blocking-ffi - Execute FFI calls in the context of haskell thread.
+dev-java/ant:antlr - Enable ANTLR Ant tasks
+dev-java/ant:bcel - Enable bcel (bytecode manipulation) Ant tasks
+dev-java/ant:commonslogging - Enable commons-logging Ant tasks
+dev-java/ant:commonsnet - Enable commons-net Ant tasks
+dev-java/ant:jai - Enable JAI (Java Imaging) Ant task
+dev-java/ant:javamail - Enable JavaMail Ant task
+dev-java/ant:jdepend - Enable Jdepend Ant tasks
+dev-java/ant:jmf - Enable JMF (Java Media Framework) Ant tasks
+dev-java/ant:jsch - Disable Jsch (ssh, scp and related) Ant tasks
+dev-java/ant:log4j - Enable Apache log4j Ant tasks
+dev-java/ant:oro - Enable Apache Oro Ant tasks
+dev-java/ant:regexp - Enable Apache Regexp Ant tasks
+dev-java/ant:resolver - Enable Apache Resolver Ant tasks
+dev-java/ant:testutil - Enable optional test util classes
+dev-java/commons-collections:test-framework - Install the test framework
+dev-java/commons-logging:avalon-framework - Add optional support for avalon-framework
+dev-java/commons-logging:avalon-logkit - Add optional support for avalon-logkit
+dev-java/commons-logging:log4j - Add optional support for log4j
+dev-java/commons-logging:servletapi - Add optional support for servletapi
+dev-java/ecj-gcj:native - Build a native binary along with the jar. Provides faster execution time, but needs about 1G memory and some patience to compile.
+dev-java/eclipse-ecj:ant - Support using ecj in Ant builds via dev-java/ant-eclipse-ecj
+dev-java/emma:launcher - Install /usr/bin/emma. Collides with sci-biology/emboss.
+dev-java/gcj-jdk:awt - Install AWT libraries, needed by some GUIs (not needed to build icedtea)
+dev-java/gnu-classpath:alsa - Build with ALSA javax.sound.midi provider
+dev-java/gnu-classpath:dssi - Build with DSSI javax.sound.midi provider
+dev-java/gnu-classpath:gconf - Build with GConf preferences backend
+dev-java/gnu-classpath:gjdoc - Build GJDoc, a documentation generator
+dev-java/gnu-classpath:gmp - Build with GMP backend for java.math.BigInteger
+dev-java/gnu-classpath:gtk - Build with Gtk+ AWT peers
+dev-java/gnu-classpath:xml - Build with native XML backend
+dev-java/icedtea:cacao - Use the CACAO virtual machine rather than HotSpot.
+dev-java/icedtea:cups - Link against the CUPS library at compile time, rather than using it dynamically at runtime.
+dev-java/icedtea:headless-awt - Don't install the X backend for AWT, needed by some GUIs (used to be X flag)
+dev-java/icedtea:jamvm - Use the JamVM virtual machine rather than HotSpot.
+dev-java/icedtea:jbootstrap - If possible, recompile the final IcedTea executables with itself.
+dev-java/icedtea:nsplugin - Enable browser plugin (NPPlugin), requires also the webstart flag to be enabled.
+dev-java/icedtea:pax_kernel - Apply patch needed for pax enabled kernels.
+dev-java/icedtea:shenandoah - Include the Shenandoah ultra-low pause time garbage collector (-XX:+UseShenandoahGC) (x86_64 only)
+dev-java/icedtea:smartcard - Build the PCSC driver against pcsc-lite
+dev-java/icedtea:sunec - Build the SunEC provider against system NSS
+dev-java/icedtea:webstart - Enable Web Start support (via NetX).
+dev-java/icedtea:zero - Enable Zero assembler port (usually for non-HotSpot architectures)
+dev-java/icedtea-bin:headless-awt - Don't install the X backend for AWT, needed by some GUIs (used to be X flag)
+dev-java/icedtea-bin:webstart - Provide javaws command through symlink to icedtea-web
+dev-java/icedtea-web:javascript - Enable support for using proxy auto config (PAC) files.
+dev-java/icedtea-web:nsplugin - Enable the browser plugin (NPPlugin).
+dev-java/icedtea-web:tagsoup - Depend on dev-java/tagsoup which allows parsing malformed .jnlp files
+dev-java/itext:rtf - Build and provide libraries for rich text format
+dev-java/itext:rups - Build and provide GUI for Reading/Updating PDF Syntax
+dev-java/jcs:admin - Enable JCS Admin servlets
+dev-java/jdbc-mysql:c3p0 - Enable c3p0 support
+dev-java/jdbc-mysql:log4j - Enable log4 support
+dev-java/jfreesvg:debug - Enable debugging during compilation.
+dev-java/jna:awt - Enables support for Java AWT
+dev-java/jna:nio-buffers - Enables support for NIO buffers
+dev-java/log4j:javamail - Build the SMTPAppender
+dev-java/log4j:jms - Build the JMSAppender
+dev-java/logback:tomcat - Builds Apache Tomcat support
+dev-java/lucene:contrib - Include extra functionality from contrib/
+dev-java/miglayout:swt - Add support for the SWT toolkit.
+dev-java/oracle-jdk-bin:commercial - Install features requiring a commercial license for production use
+dev-java/oracle-jdk-bin:derby - Install bundled Derby (Java database)
+dev-java/oracle-jdk-bin:gentoo-vm - Allow this JDK to be recognised by Gentoo (package manager, eselect, java-config, EXPERIMENTAL!)
+dev-java/oracle-jdk-bin:gtk2 - Enable GTK+ 2 support in JavaFX
+dev-java/oracle-jdk-bin:gtk3 - Enable GTK+ 3 support in JavaFX
+dev-java/oracle-jdk-bin:headless-awt - Don't install the X backend for AWT, needed by some GUIs (used to be X flag)
+dev-java/oracle-jdk-bin:javafx - Install JavaFX libraries
+dev-java/oracle-jdk-bin:jce - Install Java Cryptographic Extension Unlimited Strength Jurisdiction Policy Files
+dev-java/oracle-jdk-bin:source - Install JVM (and optionally JavaFX) sources
+dev-java/oracle-jdk-bin:visualvm - Install VisualVM debugging tool
+dev-java/oracle-jre-bin:commercial - Install features requiring a commercial license for production use
+dev-java/oracle-jre-bin:gentoo-vm - Allow this JRE to be recognised by Gentoo (package manager, eselect, java-config, EXPERIMENTAL!)
+dev-java/oracle-jre-bin:gtk2 - Enable GTK+ 2 support in JavaFX
+dev-java/oracle-jre-bin:gtk3 - Enable GTK+ 3 support in JavaFX
+dev-java/oracle-jre-bin:headless-awt - Don't install the X backend for AWT, needed by some GUIs (used to be X flag)
+dev-java/oracle-jre-bin:javafx - Install JavaFX libraries
+dev-java/oracle-jre-bin:jce - Install Java Cryptographic Extension Unlimited Strength Jurisdiction Policy Files
+dev-java/proguard:ant - Ant task for using ProGuard in build.xml scripts
+dev-java/proguard:j2me - Adds support for J2ME Wireless Toolkit
+dev-java/protobuf-java:nano - Enable code generator and runtime library designed specifically for resource-constrained systems, like Android
+dev-java/rxtx:lfd - Installs and uses LockFileServer daemon (lfd)
+dev-java/sbt:binary - Install from (Gentoo-compiled) binary instead of building from sources. Set this when you run out of memory during build.
+dev-lang/bas:lr0 - Use the LR0 parser instead of the recursive descending parser
+dev-lang/crystal:blocking-stdio-hack - Keep STDIO file descriptors in blocking mode.
+dev-lang/crystal:debug - Build each module as a separate object file. Speeds build up.
+dev-lang/crystal:xml - Use the dev-libs/libxml2 library to enable Crystal xml module
+dev-lang/crystal:yaml - Use the dev-libs/libyaml library to enable Crystal yaml module
+dev-lang/ekopath:mpich - Include pre-built MPICH libraries
+dev-lang/ekopath:openmpi - Include pre-built OpenMPI 1.x libraries
+dev-lang/ekopath:openmpi2 - Include pre-built OpenMPI 2.x libraries
+dev-lang/erlang:compat-ethread - Enable compatibility with pre-pentium 4 CPUs in the ethread library.
+dev-lang/erlang:dirty-schedulers - Enable dirty schedulers
+dev-lang/erlang:halfword - Enable halfword emulator
+dev-lang/erlang:hipe - HIgh Performance Erlang extension
+dev-lang/erlang:kpoll - Enable kernel polling support
+dev-lang/fpc:ide - Build and install the Free Pascal Compiler IDE
+dev-lang/gdl:eigen - Build matrix manipulation with dev-cpp/eigen
+dev-lang/gdl:grib - Add support for the meteorological GRIB format with sci-libs/grib_api
+dev-lang/gdl:gshhs - Add support for projection adn continent maps with sci-geosciences/gshhs-data
+dev-lang/gdl:hdf - Add support for the Hierarchical Data Format v.4
+dev-lang/gdl:proj - Add support for sci-libs/proj (geographic projections)
+dev-lang/gdl:udunits - Add support for manipulating units of physical quantities
+dev-lang/ghc:binary - Install the binary version directly, rather than using it to build the source version.
+dev-lang/ghc:ghcbootstrap - Internal: Bootstrap GHC from an existing GHC installation.
+dev-lang/ghc:ghcmakebinary - Internal: Build binary friendly for redistribution.
+dev-lang/gnat-gpl:awt - Useful only when building GCJ, this enables Abstract Window Toolkit (AWT) peer support on top of GTK+
+dev-lang/gnat-gpl:cilk - Support the Cilk Plus language (C/C++ based languages for parallel programming)
+dev-lang/gnat-gpl:fixed-point - Enable fixed-point arithmetic support for MIPS targets in gcc (Warning: significantly increases compile time!)
+dev-lang/gnat-gpl:go - Build the GCC Go language frontend.
+dev-lang/gnat-gpl:graphite - Add support for the framework for loop optimizations based on a polyhedral intermediate representation
+dev-lang/gnat-gpl:libssp - Build SSP support into a dedicated library rather than use the code in the C library (DO NOT ENABLE THIS IF YOU DON'T KNOW WHAT IT DOES)
+dev-lang/gnat-gpl:mpx - Enable support for Intel Memory Protection Extensions (MPX)
+dev-lang/gnat-gpl:nopie - Disable PIE support (NOT FOR GENERAL USE)
+dev-lang/gnat-gpl:nossp - Disable SSP support (NOT FOR GENERAL USE)
+dev-lang/gnat-gpl:objc - Build support for the Objective C code language
+dev-lang/gnat-gpl:objc++ - Build support for the Objective C++ language
+dev-lang/gnat-gpl:objc-gc - Build support for the Objective C code language Garbage Collector
+dev-lang/gnat-gpl:pgo - Build GCC using Profile Guided Optimization (PGO)
+dev-lang/gnat-gpl:regression-test - Run the testsuite and install the results (requires FEATURES=test)
+dev-lang/gnat-gpl:sanitize - Build support for various sanitizer functions (ASAN/TSAN/etc...)
+dev-lang/gnat-gpl:ssp - Build packages with stack smashing protector on by default
+dev-lang/gnat-gpl:vtv - Build support for virtual table verification (a C++ hardening feature)
+dev-lang/go:gccgo - Enable bootstrapping using gccgo
+dev-lang/icon:iplsrc - install the icon programming library source
+dev-lang/lazarus:minimal - Don't build extra packages from the bigide component
+dev-lang/logtalk:fop - Support for generating pdf documentation using fop
+dev-lang/logtalk:xslt - Support for generating html documentation using xslt
+dev-lang/lua:deprecated - make deprecated data structures/routines available
+dev-lang/luajit:lua52compat - Enable some upwards-compatible features from Lua 5.2 that are unlikely to break existing code.
+dev-lang/mercury:erlang - Support Mercury Erlang grade
+dev-lang/mercury:trail - Support Mercury trail grades
+dev-lang/mlton:binary - install a binary version (need to do this once to bootstrap, until smlnj is supported)
+dev-lang/moarvm:asan - Enable clang's Address Sanitizer functionality. Expect longer compile time.
+dev-lang/moarvm:clang - Use clang compiler instead of GCC
+dev-lang/moarvm:jit - Enable Just-In-Time-Compiler. Has no effect except on AMD64 and Darwin.
+dev-lang/moarvm:optimize - Enable optimization via CFLAGS
+dev-lang/moarvm:ubsan - Enable clang's Undefined Behavior Sanitizer functionality. Expect longer compile time.
+dev-lang/mono:pax_kernel - Enable if the user plans to run the package under a pax enabled hardened kernel
+dev-lang/mono:xen - Make mono generate code that is considerably faster on xen VMs but slightly slower on for normal systems.
+dev-lang/nqp:clang - Toggle usage of the clang compiler in conjunction with MoarVM
+dev-lang/nqp:moar - Build the MoarVM backend (experimental/broken)
+dev-lang/ocaml:flambda - Enables the Flambda optimizer: A new intermediate representation (introduced in ocaml 4.03) in the depths of the compiler designed to allow for better inlining.
+dev-lang/ocaml:spacetime - Enables the Spacetime memory profiler. See https://caml.inria.fr/pub/docs/manual-ocaml/spacetime.html for more information.
+dev-lang/orc:pax_kernel - Apply patch needed for pax enabled kernels.
+dev-lang/perl:ithreads - Enable Perl threads, has some compatibility problems
+dev-lang/php:argon2 - Enable password hashing algorithm from app-crypt/argon2
+dev-lang/php:cli - Enable CLI SAPI
+dev-lang/php:coverage - Include gcov symbols for test coverage and lcov reports. Only useful for extension developers, and requires GCC.
+dev-lang/php:embed - Enable embed SAPI
+dev-lang/php:enchant - Add supports Enchant spelling library.
+dev-lang/php:fileinfo - Add fileinfo extension support
+dev-lang/php:filter - Add filter extension support
+dev-lang/php:fpm - Enable the FastCGI Process Manager SAPI
+dev-lang/php:gd - Adds support for gd (bundled with PHP)
+dev-lang/php:hash - Enable the hash extension
+dev-lang/php:intl - Enables the intl extension for extended internalization support
+dev-lang/php:json - Enable JSON support
+dev-lang/php:ldap-sasl - Add SASL support for the PHP LDAP extension
+dev-lang/php:libmysqlclient - Use libmyslclient driver for mysql, mysqli, PDO_Mysql (not recommended)
+dev-lang/php:lmdb - Enable support for dev-db/lmdb db backend
+dev-lang/php:opcache - Enables built-in opcode cache, replacing pecl-apc et al.
+dev-lang/php:pdo - Enable the bundled PDO extensions
+dev-lang/php:phar - Enables the phar extension to provide phar archive support
+dev-lang/php:phpdbg - Enable the PHP Debug Command Line SAPI (like gdb for php)
+dev-lang/php:session-mm - Include dev-libs/mm support for session storage
+dev-lang/php:sodium - Enable support for crypto through dev-libs/libsodium
+dev-lang/php:tokyocabinet - Enable support for dev-db/tokyocabinet db backend
+dev-lang/php:vpx - Enable webp support for GD in php-5.x
+dev-lang/php:webp - Enable webp support for GD in php-7.x
+dev-lang/php:xmlreader - Enable XMLReader support
+dev-lang/php:xmlwriter - Enable XMLWriter support
+dev-lang/php:xslt - Enable the XSL extension
+dev-lang/php:zip - Enable ZIP file support
+dev-lang/php:zip-encryption - Enable ZIP file encryption from dev-libs/libzip
+dev-lang/polyml:portable - Build the portable interpreter version of Poly/ML instead of native
+dev-lang/python:threads - Enable threading support. (DON'T DISABLE THIS UNLESS YOU KNOW WHAT YOU'RE DOING)
+dev-lang/python:wide-unicode - Enable wide Unicode implementation which uses 4-byte Unicode characters. Switching of this USE flag changes ABI of Python and requires reinstallation of many Python modules. (DON'T DISABLE THIS UNLESS YOU KNOW WHAT YOU'RE DOING)
+dev-lang/python:wininst - Install Windows executables required to create an executable installer for MS Windows.
+dev-lang/qu-prolog:pedro - Pedro subscription/notification communications system
+dev-lang/rakudo:clang - Use Clang to compile the MoarVM backend
+dev-lang/rakudo:moar - Use the MoarVM as backend
+dev-lang/rubinius:llvm - Build with llvm. Currently the package only builds against old versions of llvm.
+dev-lang/ruby:jemalloc - Use dev-libs/jemalloc for memory allocation.
+dev-lang/ruby:rdoc - Install dev-ruby/rdoc after installing Ruby.
+dev-lang/ruby:readline - Use the sys-libs/readline library to provide the readline extension, used for instance by the irb tool. This flag is meaningful only if the libedit USE flag is disabled. If neither libedit nor readline USE flags are enabled, the readline extension will not be built (and irb will lose line editing functionality).
+dev-lang/ruby:rubytests - Install ruby tests that can only be run after ruby is installed
+dev-lang/rust:clang - Use sys-devel/clang for building
+dev-lang/rust:extended - Build and install rls, rustfmt and cargo alongside the compiler and stdlib
+dev-lang/rust:jemalloc - Use dev-libs/jemalloc as the standard memory allocator
+dev-lang/rust:libcxx - Use sys-libs/libcxx as standard library when building with sys-devel/clang
+dev-lang/rust:system-llvm - Use system sys-devel/llvm in place of the bundled one
+dev-lang/scala:binary - Install from (Gentoo-compiled) binary instead of building from sources. Set this when you run out of memory during build.
+dev-lang/spidermonkey:custom-optimization - Build with user-specified compiler optimizations (-Os, -O0, -O1, -O2, -O3) from CFLAGS (unsupported)
+dev-lang/spidermonkey:debug - Enable assertions to allow for easier debugging of programs that link to spidermonkey -- note this will often crash software on regular end-user systems
+dev-lang/spidermonkey:system-icu - Use the system-wide dev-libs/icu instead of bundled -- note, only takes effect when icu flag is enabled
+dev-lang/spidermonkey:threadsafe - Build a threadsafe version of spidermonkey
+dev-lang/swi-prolog:archive - Use libarchive for extension packs
+dev-lang/swi-prolog:uuid - Use ossp-uuid for UUID pack
+dev-lang/swig:ccache - build ccache-swig(a fast compiler cache)
+dev-lang/yap:R - Enable support for connecting R to Prolog
+dev-libs/DirectFB:bmp - build BMP image provider
+dev-libs/DirectFB:divine - enable DiVine
+dev-libs/DirectFB:drmkms - build with DRM/KMS support
+dev-libs/DirectFB:dynload - enable dynload support
+dev-libs/DirectFB:egl - build with EGL support
+dev-libs/DirectFB:fusiondale - enable FusionDale
+dev-libs/DirectFB:fusionsound - enable FusionSound
+dev-libs/DirectFB:gles2 - build gles2 gfxdriver
+dev-libs/DirectFB:imlib2 - build Imlib2 image provider
+dev-libs/DirectFB:input_hub - provides an asynchronous interface to the input devices available and those being added/removed
+dev-libs/DirectFB:mpeg2 - build MPEG2 image provider
+dev-libs/DirectFB:mpeg3 - build Libmpeg3 video provider
+dev-libs/DirectFB:multicore - enable multicore support
+dev-libs/DirectFB:pnm - build PNM (PBM/PGM/PPM) image provider
+dev-libs/DirectFB:sawman - enable SaWMan (window manager and application manager)
+dev-libs/DirectFB:swfdec - build Swfdec (Flash decoder) video provider
+dev-libs/DirectFB:tremor - build Ogg/Vorbis music provider using Tremor
+dev-libs/DirectFB:webp - build WebP image provider
+dev-libs/ace:ciao - Include Component Intergraced Ace ORB into the build of ace
+dev-libs/ace:tao - Include the ACE ORB (CORBA stuff) (called tao) into the build of ace
+dev-libs/actor-framework:benchmarks - Due to the number of out-of-tree deps, these only get installed as docs
+dev-libs/actor-framework:boost - Make use of Boost's ASIO functionality
+dev-libs/actor-framework:cash - Build the C Actor Shell for introspection and debugging
+dev-libs/actor-framework:debug - Raises log-level to DEBUG, enables runtime checks and address sanitizer
+dev-libs/actor-framework:doc - Compiles and installs the documentation as PDF and HTML
+dev-libs/actor-framework:examples - Installs the provided example source files
+dev-libs/actor-framework:mem_management - Enables built-in memory management
+dev-libs/actor-framework:nexus - Nexus is the central component for CAF's runtime inspection
+dev-libs/actor-framework:opencl - Compiles against the provided opencl implementation
+dev-libs/actor-framework:riac - Runtime inspection and configuration
+dev-libs/actor-framework:static - Provides a static build
+dev-libs/actor-framework:test - Builds the provided unit tests
+dev-libs/antlr-c:debugger - Compiles debug info into the library
+dev-libs/appstream:apt - Enables Debians APT support
+dev-libs/appstream-glib:stemmer - Add word stemming via dev-libs/snowball-stemmer.
+dev-libs/apr:older-kernels-compatibility - Enable binary compatibility with older kernels
+dev-libs/apr:urandom - Use /dev/urandom instead of /dev/random
+dev-libs/apr-util:libressl - Use dev-libs/libressl instead of dev-libs/openssl for 'openssl' USE flag
+dev-libs/apr-util:nss - Install apr_crypto_nss module
+dev-libs/apr-util:openssl - Install apr_crypto_openssl module
+dev-libs/atcore:gui - Build test GUI
+dev-libs/beignet:ocl-icd - Enable compatibility with the dev-libs/ocl-icd OpenCL ICD loader
+dev-libs/beignet:ocl20 - Enable experimental OpenCL 2.0 support on Skylake and newer architectures
+dev-libs/bitset:jemalloc - Use dev-libs/jemalloc for allocations
+dev-libs/bitset:tcmalloc - Use tcmalloc from dev-util/google-perftools for allocations
+dev-libs/blitz:boost - Enable usage of boost::serialization
+dev-libs/boost:context - Build and install the Boost.Context (and Boost.Fiber) library and all other Boost libraries that depend on it
+dev-libs/boost:debug - Build and install only the debug version of the Boost libraries. Only enable this flag if you're developing against boost.
+dev-libs/boost:doc - Install the full API documentation documentation. This takes over 200MB of extra disk space.
+dev-libs/boost:nls - Build libboost_locale. This library requires compatible C library interfaces, which might not be provided by uClibc or other embedded libraries.
+dev-libs/boost:threads - Build multi-thread-compatible libraries instead of single-threaded only.
+dev-libs/boost:tools - Build and install the boost tools (bcp, quickbook, inspect, wave)
+dev-libs/botan:boost - use dev-libs/boost
+dev-libs/c-blosc:lz4 - Enable lz4 compression
+dev-libs/c-blosc:snappy - Enable snappy compression
+dev-libs/c-blosc:zstd - Enable zstd compression
+dev-libs/check:subunit - Enable support for the subunit unit test protocol
+dev-libs/cyberjack:fox - Enable installation of x11-libs/fox based fxcyberjack program
+dev-libs/cyrus-sasl:authdaemond - Add Courier-IMAP authdaemond unix socket support (net-mail/courier-imap, mail-mta/courier)
+dev-libs/cyrus-sasl:ldapdb - Enable ldapdb plugin
+dev-libs/cyrus-sasl:openldap - Add ldap support for saslauthd
+dev-libs/cyrus-sasl:sample - Enable sample client and server
+dev-libs/cyrus-sasl:srp - Enable SRP authentication
+dev-libs/cyrus-sasl:urandom - Use /dev/urandom instead of /dev/random
+dev-libs/dbus-c++:ecore - Use Ecore integration
+dev-libs/dbus-c++:glib - Use glib integration
+dev-libs/eekboard:libcanberra - Enable support for media-libs/libcanberra
+dev-libs/eekboard:xtest - Enable support for x11-libs/libXtst
+dev-libs/efl:bmp - Enable WBMP image loader
+dev-libs/efl:drm - Enable DRM engine
+dev-libs/efl:eet - Enable Eet image loader
+dev-libs/efl:egl - Enable EGL rendering
+dev-libs/efl:fribidi - Enable bidirectional text support
+dev-libs/efl:gles - Enable the OpenGL ES GL implementation
+dev-libs/efl:glib - Enable dev-libs/glib support
+dev-libs/efl:harfbuzz - Enable complex text shaping and layout support
+dev-libs/efl:ibus - Enable Intelligent Input Bus
+dev-libs/efl:ico - Enable Ico image loader
+dev-libs/efl:oldlua - USE dev-lang/lua instead of dev-lang/luajit
+dev-libs/efl:physics - Enable Bullet physics effects and support
+dev-libs/efl:pixman - Enable PixMan for software rendering
+dev-libs/efl:ppm - Enable PMAPS image loader
+dev-libs/efl:psd - Enable PSD image loader
+dev-libs/efl:scim - Enable Smart Common Input Method
+dev-libs/efl:tga - Enable Tga image loader
+dev-libs/efl:tslib - Enable x11-libs/tslib for touchscreen events
+dev-libs/efl:unwind - Enable debug support via sys-libs/libunwind
+dev-libs/efl:valgrind - Enable usage of dev-util/valgrind in debug
+dev-libs/efl:webp - Enable WebP image loader
+dev-libs/efl:xim - Enable X Input Method
+dev-libs/elfutils:lzma - Support automatic decompression of LZMA-compressed files and kernel images
+dev-libs/elfutils:threads - Build the libraries with thread safe support
+dev-libs/elfutils:utils - Install command-line utilities (all the eu-* programs)
+dev-libs/fcgi:html - Install HTML documentation
+dev-libs/folks:telepathy - Load contacts from the Telepathy framework
+dev-libs/folks:tracker - Load contacts from app-misc/tracker index
+dev-libs/folks:utils - Build the folks-inspect utility
+dev-libs/folks:zeitgeist - Add support for Zeitgeist event tracking system
+dev-libs/fstrm:utils - Build fstrm utility programs
+dev-libs/gecode:gist - Enable Gist, the Gecode Interactive Search Tool
+dev-libs/gecode:gmp - Enable trigonometric and transcendental float constraints
+dev-libs/gf2x:bindist - Disable automatic fine-tuning to local processor features like pclmul or sse2.
+dev-libs/gf2x:custom-tune - Extra long compile time for tuning hardware specific low-level routines
+dev-libs/gf2x:fft - Build an FFT API for multiplication of 2 polynomials over GF(2)
+dev-libs/glib:dbus - Enable dependencies required by glib libraries using dbus service to manage settings saving
+dev-libs/glib:mime - Pull in shared MIME database that many glib-based applications require at runtime to detect or open files. Warning: do not disable this flag unless installing on a headless server.
+dev-libs/glib:systemtap - Build support for profiling and tracing using dev-util/systemtap
+dev-libs/glib:utils - Install gtester-report utility to generate test report files for your software; build gresource utility with ELF support.
+dev-libs/gmime:smime - Enable experimental S/MIME support
+dev-libs/gmp:asm - Enable use of hand optimized assembly routines (faster execution)
+dev-libs/gmp:pgo - After building gmp, run some tests against to produce faster libraries -- this option will double the compile time
+dev-libs/gobject-introspection:doctool - Install g-ir-doc-tool for generating documentation from introspected data
+dev-libs/granite:demo - Build the Granite demo application (to present all available UI features provided by the library)
+dev-libs/hidapi:fox - Build a x11-libs/fox GUI
+dev-libs/input-pad:eekboard - Enable support for dev-libs/eekboard
+dev-libs/input-pad:xtest - Enable support for x11-libs/libXtst
+dev-libs/intel-common:compiler - Install the libraries needed for the icc and ifort compilers
+dev-libs/jemalloc:hugepages - Enable transparent huge page support
+dev-libs/jemalloc:lazy-lock - Enable lazy locking (only lock when multi-threaded)
+dev-libs/jemalloc:stats - Enable statistics calculation/reporting
+dev-libs/jemalloc:xmalloc - Add support for xmalloc (abort-on-out-of-memory)
+dev-libs/kreport:marble - Enable displaying of maps using kde-apps/marble
+dev-libs/kreport:scripting - Support Qml scripting using dev-qt/qtdeclarative
+dev-libs/leveldb:snappy - support the snappy compression library
+dev-libs/libbase58:tools - Build command line base58 tool
+dev-libs/libcdio:minimal - Only build the libcdio library and little more, just to be used to link against from multimedia players. With this USE flag enabled, none of the command-line utilities are built, nor is the CDDA library.
+dev-libs/libcec:cubox - Enable support for enable support for the TDA995x
+dev-libs/libcec:exynos - Enable support for Exynos chipsets
+dev-libs/libcec:raspberry-pi - Enable support for the Raspberry Pi
+dev-libs/libcec:xrandr - Enable detection of active HDMI using xrandr extensions
+dev-libs/libcgroup:daemon - Install the configuration tools and init/config files.
+dev-libs/libcgroup:tools - Install the cgroup rules processing daemon and init/config files.
+dev-libs/libclsync:extra-debug - Enable extra debugging. This will hurt performance badly. Be ready for tons of output.
+dev-libs/libclsync:extra-hardened - Enable extra security checks. This may hurt performance.
+dev-libs/libdbusmenu:gtk - Enable support for GTK+2
+dev-libs/libdbusmenu:gtk3 - Enable support for GTK+3
+dev-libs/libdivecomputer:tools - Install tools that can be used to test the library.
+dev-libs/libdynd:cuda - Enable NVIDIA CUDA toolkit support
+dev-libs/libdynd:mkl - Enable a plugin for Intel Math Kernel Library sci-libs/mkl
+dev-libs/libevent:debug - Support runtime debug mode and malloc hooks (for programmers)
+dev-libs/libffi:pax_kernel - Use PaX emulated trampolines, for we can't use PROT_EXEC
+dev-libs/libflatarray:cuda - Enables plugins for NVIDIA GPUs (e.g. CUDAAllocator)
+dev-libs/libgcrypt:o-flag-munging - Enable O-flag mangling during build
+dev-libs/libgdata:gnome-online-accounts - Enable net-libs/gnome-online-accounts support
+dev-libs/libgit2:gssapi - Enable GSSAPI support for SPNEGO auth
+dev-libs/libgit2:ssh - Enable SSH transport support
+dev-libs/libgit2:trace - Enable tracing support
+dev-libs/libgit2-glib:ssh - Enable SSH transport support
+dev-libs/libgpg-error:common-lisp - Install common-lisp files
+dev-libs/libgpuarray:cuda - Enable NVIDIA CUDA toolkit support
+dev-libs/libgpuarray:opencl - Enable OpenCL support
+dev-libs/libgweather:glade - Installs catalog files for dev-util/glade
+dev-libs/libisoburn:external-filters - Allow the use of external processes as file content filters (Note: this is a potential security risk)
+dev-libs/libisoburn:external-filters-setuid - Also allow the use of external setuid processes as file content filters (Note: this is a potential security risk)
+dev-libs/libisoburn:frontend-optional - Use dev-tcltk/bwidget which is not strictly required for the frontend
+dev-libs/libisoburn:launch-frontend - Enable the tcl gui for xorriso
+dev-libs/libisoburn:launch-frontend-setuid - Enable the tcl gui for xorriso under setuid
+dev-libs/libisofs:verbose-debug - Enable verbose debug messages
+dev-libs/liblogging:rfc3195 - Enables RFC 3195 protocol (aka syslog-reliable) support. If you don't know what this is, you don't need it!
+dev-libs/liblogging:stdlog - Enables liblogging's core component (think of it as a the next version of the syslog(3) API).
+dev-libs/libmail:apop - Enables the APOP authentication method
+dev-libs/libmateweather:gtk3 - Build with GTK+3 instead of GTK+2
+dev-libs/libmemcached:hsieh - Use Hsieh hash algorithm.
+dev-libs/libmemcached:libevent - Use the libevent event loop interface.
+dev-libs/libmemcached:sasl - Use sasl auth for communications.
+dev-libs/libmspack:utils - Enables building cabrip, chmextract, msexpand and oabextract
+dev-libs/libnfc:pcsc-lite - Enable NFC drivers that require pcsc-lite
+dev-libs/libnl:doc - Install development documentation
+dev-libs/libnl:python - Install experimental dev-lang/python bindings
+dev-libs/libnl:utils - Install command line interface utils
+dev-libs/liborcus:spreadsheet-model - Enable the spreadsheet model implementation
+dev-libs/liborcus:tools - Build various low-level parsers
+dev-libs/libowfat:diet - Compile against dev-libs/dietlibc
+dev-libs/libp11:doc - Generate and install API documentation for the package.
+dev-libs/libpcre:bzip2 - Add support for pcregrep command to search within bzip2-compressed files (via app-arch/bzip2).
+dev-libs/libpcre:pcre16 - Build PCRE library for 16 bit characters (e.g. UTF-16).
+dev-libs/libpcre:pcre32 - Build PCRE library for 32 bit characters (e.g. UTF-32).
+dev-libs/libpcre:readline - Add support for command line editing to pcretest, through sys-libs/readline.
+dev-libs/libpcre:recursion-limit - Limit match recursion to 8192; if disabled, the default limit is used, which is the same as the match limit.
+dev-libs/libpcre:zlib - Add support for pcregrep command to search within gzip-compressed files (via sys-libs/zlib).
+dev-libs/libpcre2:bzip2 - Add support for pcregrep command to search within bzip2-compressed files (via app-arch/bzip2).
+dev-libs/libpcre2:pcre16 - Build PCRE library for 16 bit characters (e.g. UTF-16).
+dev-libs/libpcre2:pcre32 - Build PCRE library for 32 bit characters (e.g. UTF-32).
+dev-libs/libpcre2:readline - Add support for command line editing to pcretest, through sys-libs/readline.
+dev-libs/libpcre2:recursion-limit - Limit match recursion to 8192; if disabled, the default limit is used, which is the same as the match limit.
+dev-libs/libpcre2:zlib - Add support for pcregrep command to search within gzip-compressed files (via sys-libs/zlib).
+dev-libs/libpeas:glade - Install the glade catalog
+dev-libs/libpeas:python - Build support for loading dev-lang/python plugins
+dev-libs/librdkafka:lz4 - Enable support for Kafka's LZ4 compression based on KIP-57 (uses app-arch/lz4)
+dev-libs/libressl:asm - Enables assembly
+dev-libs/libsecp256k1:asm - Enable x86_64 assembly optimisation
+dev-libs/libsecp256k1:ecdh - Enable ECDH shared secret computation
+dev-libs/libsecp256k1:endomorphism - Enable endomorphism
+dev-libs/libsecp256k1:experimental - Allow experimental USE flags
+dev-libs/libsecp256k1:recovery - Enable ECDSA pubkey recovery module
+dev-libs/libsecp256k1:schnorr - Enable Schnorr signature module
+dev-libs/libsecp256k1:test_openssl - Enable OpenSSL comparison tests
+dev-libs/libslz:tools - Install additional tools (zenc, zdec)
+dev-libs/libsodium:asm - Enables assembly implementations
+dev-libs/libsodium:urandom - Use /dev/urandom instead of /dev/random
+dev-libs/libsolv:rpm - Enable support for RPM files
+dev-libs/libspt:libtirpc - Build against net-libs/libtirpc for RPC support
+dev-libs/libsqlora8:orathreads - Use Oracle threads
+dev-libs/libtasn1:valgrind - Enable usage of dev-util/valgrind in debug
+dev-libs/libtermkey:demos - Install demos, which pulls in dev-libs/glib
+dev-libs/libucl:regex - Enable regex checking for schema
+dev-libs/libucl:signatures - Enable signatures check
+dev-libs/libucl:urlfetch - Enable URLs fetch
+dev-libs/libucl:utils - Install the chargen and objdump utilities
+dev-libs/libunibreak:doc - Install html API documentation.
+dev-libs/libunibreak:man - Generate man pages with doxygen.
+dev-libs/libverto:glib - Support event loops using dev-libs/glib
+dev-libs/libverto:libev - Support event loops using dev-libs/libev
+dev-libs/libverto:libevent - Support event loops using dev-libs/libevent
+dev-libs/libverto:tevent - Support event loops using sys-libs/tevent
+dev-libs/libzia:ftdi - Enable support for FTDI USB chips
+dev-libs/link-grammar:aspell - Adds support for app-text/aspell spell checker
+dev-libs/link-grammar:hunspell - Adds support for app-text/hunspell spell checker
+dev-libs/log4cplus:iconv - Use inconv for wchar_t <-> char conversions. See also log4cplus's unicode.txt documentation
+dev-libs/log4cplus:working-c-locale - Use the C99 locale facilities for wchar_t <-> char conversions. See also log4cplus's unicode.txt documentation
+dev-libs/log4cplus:working-locale - Use C++'s std::locale for wchar_t <-> char conversions. See also log4cplus's unicode.txt documentation
+dev-libs/log4cxx:smtp - Offer SMTP support via net-libs/libesmtp
+dev-libs/m17n-lib:X - Build the Graphical User Interface API and utilities
+dev-libs/m17n-lib:anthy - Enable support for app-i18n/anthy input method
+dev-libs/m17n-lib:athena - Enable the MIT Athena widget set (x11-libs/libXaw)
+dev-libs/m17n-lib:gd - Build API and utilities based on media-libs/gd. This flag is only meaningful if the X USE flag is also enabled.
+dev-libs/m17n-lib:libotf - Use dev-libs/libotf to handle OpenType fonts
+dev-libs/m17n-lib:libxml2 - Use dev-libs/libxml2 to parse XML
+dev-libs/nss:cacert - Include root/class3 certs from CAcert (http://www.cacert.org/)
+dev-libs/nss:nss-pem - Add support for libnsspem
+dev-libs/nss:utils - Install utilities included with the library
+dev-libs/onigmo:combination-explosion-check - enable combination explosion check
+dev-libs/onigmo:crnl-as-line-terminator - enable CR+NL as line terminator
+dev-libs/oniguruma:combination-explosion-check - enable combination explosion check
+dev-libs/oniguruma:crnl-as-line-terminator - enable CR+NL as line terminator
+dev-libs/opencryptoki:tpm - Enable support for Trusted Platform Module (TPM) using app-crypt/trousers
+dev-libs/openct:debug - Add debug output to the driver library for pcsc-lite.
+dev-libs/openct:pcsc-lite - Build a driver library for sys-apps/pcsc-lite, providing PC/SC API access to devices supported by OpenCT.
+dev-libs/openct:udev - Install rules for sys-fs/udev to auto-start openct.
+dev-libs/openobex:irda - Enable IrDA support
+dev-libs/opensc:ctapi - Use CT-API for accessing Smartcard hardware
+dev-libs/opensc:openct - Use dev-libs/openct (and CT-API) for accessing Smartcard hardware
+dev-libs/opensc:pcsc-lite - Use sys-apps/pcsc-lite (and PC/SC API) for accessing Smartcard hardware
+dev-libs/opensc:secure-messaging - Enable secure messaging
+dev-libs/openssl:asm - Support assembly hand optimized crypto functions (i.e. faster run time)
+dev-libs/openssl:bindist - Disable/Restrict EC algorithms (as they seem to be patented) -- note: changes the ABI
+dev-libs/openssl:rfc3779 - Enable support for RFC 3779 (X.509 Extensions for IP Addresses and AS Identifiers)
+dev-libs/openssl:sslv2 - Support for the old/insecure SSLv2 protocol -- note: not required for TLS/https
+dev-libs/openssl:sslv3 - Support for the old/insecure SSLv3 protocol -- note: not required for TLS/https
+dev-libs/openssl:tls-heartbeat - Enable the Heartbeat Extension in TLS and DTLS
+dev-libs/pkcs11-helper:nss - Enable NSS crypto engine
+dev-libs/poco:7z - Add Support for the 7z archive format
+dev-libs/poco:apache - Enable support to write Apache modules using POCO
+dev-libs/poco:cppparser - Build and install a minimal C++ parser
+dev-libs/poco:crypto - Encryption and digital signing classes
+dev-libs/poco:data - Database abstraction layer to easily send/retrieve data to/from various databases
+dev-libs/poco:file2pagecompiler - Utility to convert ordinary files to Page Compiler source files
+dev-libs/poco:json - Add JSON support
+dev-libs/poco:mongodb - Add dev-db/mongodb support
+dev-libs/poco:net - Classes to write network clients & servers
+dev-libs/poco:pagecompiler - Simple compiler translating HTML pages containing embedded C++ code into HTTPRequestHandler classes
+dev-libs/poco:pocodoc - POCO documentation generator
+dev-libs/poco:util - Several utility classes (like logger, timer, config file parser)
+dev-libs/poco:zip - Add support for the zip & gz archive formats
+dev-libs/ppl:lpsol - Build the ppl_lpsol linear programming problem solver
+dev-libs/protobuf:java - Builds the Java implementation. This is not needed for Java support in protoc.
+dev-libs/protobuf:python - Builds the Python implementation. This is not needed for Python support in protoc.
+dev-libs/softhsm:migration-tool - Build db migration tool
+dev-libs/starpu:cuda - Enable NVIDIA CUDA toolkit support
+dev-libs/starpu:gcc-plugin - Enable GCC extension plugin (experimental)
+dev-libs/starpu:opencl - Enable OpenCL support
+dev-libs/sway:gdk-pixbuf - Enable additional image format support via the x11-libs/gdk-pixbuf library.
+dev-libs/sway:swaybar - Build 'swaybar': sway's status bar component.
+dev-libs/sway:swaybg - Build 'swaybg': allows to set a desktop background image.
+dev-libs/sway:swaygrab - Build 'swaygrab': allows taking screenshots or screencasts.
+dev-libs/sway:swaylock - Build 'swaylock': sway's screen locker.
+dev-libs/sway:swaymsg - Build 'swaymsg': tool for communicating with a running sway instance.
+dev-libs/sway:tray - Enable support for StatusNotifierItem tray specification.
+dev-libs/sway:wallpapers - Install sway's default wallpaper image.
+dev-libs/tinyxml:stl - Compile with TIXML_USE_STL support
+dev-libs/tntnet:server - Enable tntnet server daemon
+dev-libs/totem-pl-parser:archive - Enables support for accessing media files in archives transparently via app-arch/libarchive
+dev-libs/totem-pl-parser:quvi - Use media-libs/libquvi for parsing video links
+dev-libs/tvision:gpm - Support text mode mouse through sys-libs/gpm
+dev-libs/ucommon:socks - Build with socks proxy support
+dev-libs/userspace-rcu:regression-test - Run regression tests (requires FEATURES=test)
+dev-libs/ustr:ustr-import - Install ustr-import developer program and source code for bundling.
+dev-libs/weston:colord - Allow setting color managment
+dev-libs/weston:drm - Enable drm compositor support
+dev-libs/weston:editor - Install wayland-editor example application
+dev-libs/weston:fbdev - Enable fbdev compositor support
+dev-libs/weston:gles2 - Use GLESv2 cairo instead of full GL
+dev-libs/weston:headless - Headless backend and a noop renderer, mainly for testing purposes
+dev-libs/weston:ivi - Enable the IVI shell
+dev-libs/weston:launch - Install weston-launch utility
+dev-libs/weston:rdp - Enable Remote Desktop Protocol compositor support
+dev-libs/weston:resize-optimization - Increase performance, allocate more RAM. Recommended to disable on Raspberry Pi
+dev-libs/weston:rpi - Raspberry Pi GPU support
+dev-libs/weston:screen-sharing - Enable screen-sharing through RDP
+dev-libs/weston:unwind - Enable libunwind usage for backtraces
+dev-libs/weston:wayland-compositor - Enable Wayland compositor support
+dev-libs/weston:webp - Add support for the WebP image format
+dev-libs/weston:xwayland - Enable ability support native X11 applications
+dev-libs/wlc:X - Enable X11 backend.
+dev-libs/wlc:systemd - Enable support for systemd-logind.
+dev-libs/wlc:xwayland - Enable XWayland application support.
+dev-libs/xapian:brass - Enabled brass backend db support
+dev-libs/xapian:chert - Enabled chert backend db support
+dev-libs/xapian:glass - Enabled glass backend db support
+dev-libs/xapian:inmemory - Enabled inmemory backend db support
+dev-libs/xerces-c:iconv - Use iconv (virtual/libiconv) as message loader and transcoder (in general it would be possible to use iconv only as message loader and something else like icu or the native method as transcoder and vice-versa, but this is a less common case and hard to handle)
+dev-libs/xerces-c:threads - Enable threading support through pthread (or other libraries on AIX, IRIX, HPUX, Solars). Highly recommended
+dev-libs/xml-security-c:nss - Use dev-libs/nss for certain crypto operations (configureable at runtime)
+dev-libs/xml-security-c:xalan - Enable support for XSLT and XPath parsing by dev-libs/xalan-c
+dev-libs/xmlrpc-c:abyss - Build the Abyss mini web-server.
+dev-libs/xmlrpc-c:libxml2 - Use dev-libs/libxml2 to parse XML instead of the internal expat library.
+dev-libs/xmlrpc-c:threads - Controls whether to build the Abyss web-server with pthreads or fork 'threading'.
+dev-libs/xmlrpc-c:tools - Build the xmlrpc* tools.
+dev-libs/xmlsec:gcrypt - Install xmlsec-gcrypt library
+dev-libs/xmlsec:gnutls - Install xmlsec-gnutls library
+dev-libs/xmlsec:nss - Install xmlsec-nss library
+dev-libs/xmlsec:openssl - Install xmlsec-openssl library
+dev-libs/xqilla:faxpp - Use dev-libs/faxpp instead of Xerces-C for certain tasks
+dev-libs/xqilla:htmltidy - Use app-text/htmltidy when parsing HTML
+dev-libs/yaz:ziffy - Install ziffy, a promiscuous Z39.50 APDU sniffer
+dev-lisp/abcl:clisp - Build Armed Bear Common Lisp using GNU CLISP
+dev-lisp/abcl:cmucl - Build Armed Bear Common Lisp using CMU Common Lisp
+dev-lisp/abcl:jad - Enable support for disassembling compiled code using JAD
+dev-lisp/clisp:hyperspec - Use local hyperspec instead of online version
+dev-lisp/clisp:new-clx - Build CLISP with support for the NEW-CLX module which is a -C binding to the Xorg libraries
+dev-lisp/clisp:pari - Build CLISP with support for the PARI Computer Algebra System
+dev-lisp/clisp:svm - Build CLISP with support for the Support Vector Machine module
+dev-lisp/clx:doc - Builds documentation
+dev-lisp/cmucl:source - Include source code for CMUCL in installation
+dev-lisp/ecls:gengc - Use generational garbage collection (experimental)
+dev-lisp/ecls:libatomic - Use dev-libs/libatomic_ops library
+dev-lisp/ecls:precisegc - Use type information during garbage collection (experimental)
+dev-lisp/gcl:ansi - Build a GCL with ANSI support (else build a traditional CLtL1 image)
+dev-lisp/gcl:athena - Build xgcl - an interface to x11-libs/libXaw
+dev-lisp/sbcl:pax_kernel - Enable if the user plans to run the package under a pax enabled hardened kernel
+dev-lua/lpeg:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/lua-openssl:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/luacheck:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/luafilesystem:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/luaossl:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/luarocks:curl - Uses net-misc/curl for fetching lua packages instead of net-misc/wget.
+dev-lua/luarocks:openssl - Uses dev-libs/openssl for verifying lua packages instead of md5sum.
+dev-lua/luassert:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/luvit:bundled-libs - Use bundled versions of some libraries.
+dev-lua/messagepack:luajit - Use the lua just-in-time compiler dev-lang/luajit instead of dev-lang/lua
+dev-lua/mpack:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-lua/say:luajit - Use dev-lang/luajit instead of dev-lang/lua
+dev-ml/cairo-ocaml:pango - Enable support for x11-libs/pango
+dev-ml/csv:lwt - Enables the Lwt-based library for asynchronous operations.
+dev-ml/dose3:parmap - Adds multi-core CPU support via dev-ml/parmap.
+dev-ml/dose3:rpm4 - Adds support for handling rpm4 files.
+dev-ml/dose3:zip - Adds support for handling zip files.
+dev-ml/eliom:ppx - Enable PPX syntax extension support.
+dev-ml/js_of_ocaml:camlp4 - Build with camlp4 syntax extensions.
+dev-ml/js_of_ocaml:deriving - Enable dev-ml/deriving support for improving the type safety.
+dev-ml/js_of_ocaml:lwt - Enable dev-ml/lwt support.
+dev-ml/js_of_ocaml:ppx - Enables the ppx syntax extension
+dev-ml/js_of_ocaml:react - Enable functionnal reactive programming support.
+dev-ml/lablgtk:glade - Enable libglade bindings compilation.
+dev-ml/lablgtk:gnomecanvas - Enable libgnomecanvas bindings compilation.
+dev-ml/lablgtk:sourceview - Enable GtkSourceView support
+dev-ml/logs:cli - Enables the Logs_cli library that provides command line support for controlling Logs.
+dev-ml/logs:fmt - Enables the Logs_fmt reporter.
+dev-ml/logs:lwt - Enables the Logs_lwt library that provides Lwt logging functions.
+dev-ml/lwt:camlp4 - Enable camlp4 syntax extension
+dev-ml/lwt:libev - Enable the dev-libs/libev-based backend.
+dev-ml/lwt:ppx - Enables the ppx syntax extension
+dev-ml/ocaml-cohttp:async - Enables support for the dev-ml/async asynchronous execution library.
+dev-ml/ocaml-cohttp:lwt - Enables support for the dev-ml/lwt cooperative light-weight thread library.
+dev-ml/ocaml-cstruct:async - Support for asynchronous execution
+dev-ml/ocaml-cstruct:lwt - Enable threads via lwt
+dev-ml/ocaml-cstruct:ppx - Enable the ppx syntax extension
+dev-ml/ocaml-websocket:async - Enables support for the dev-ml/async asynchronous execution library.
+dev-ml/ocaml-websocket:lwt - Enables support for the dev-ml/lwt cooperative light-weight thread library.
+dev-ml/ocamlnet:httpd - Enables net-httpd web server component
+dev-ml/ocamlnet:zip - Enables netzip support to read/write gzip data using object channels
+dev-ml/onanomsg:lwt - Enables lwt support.
+dev-ml/pgocaml:camlp4 - Enable PG'Ocaml syntax extension.
+dev-ml/tyxml:camlp4 - Enables the camlp4 syntax extension (deprecated)
+dev-ml/tyxml:ppx - Enables the ppx syntax extension (preferred)
+dev-ml/uutf:utftrip - Builds and install the utftrip executable: Among other things, reads unicode on stdin and rewrites it on stdout.
+dev-ml/zarith:mpir - Use MPIR library instead of GMP.
+dev-perl/App-Nopaste:browser - Spawn browser with pasted page
+dev-perl/App-Nopaste:clipboard - copying of URLs with -x/--copy
+dev-perl/App-Nopaste:github - Github authentication
+dev-perl/App-Nopaste:pastebin - pastebin.com support
+dev-perl/Business-ISBN:barcode - Install dev-perl/GD-Barcode for rendering ISBN numbers as barcodes
+dev-perl/Business-ISBN:xisbn - Install dev-perl/Mojolicious for querying xisbn.worldcat.org
+dev-perl/Config-Any:conf - Install dev-perl/Config-General to support decoding .conf/.cnf files
+dev-perl/Config-Any:ini - Install dev-perl/Config-Tiny to support decoding INI config files
+dev-perl/Config-Any:json - Install support libraries to support decoding JSON config files
+dev-perl/Config-Any:xml - Install support libraries to support decoding XML config files
+dev-perl/Config-Any:yaml - Install support libraries to support decoding YAML config files
+dev-perl/Convert-UUlib:system-uulib - Use dev-libs/uulib instead of bundled version.
+dev-perl/Cookie-Baker:xs - Install dev-perl/Cookie-Baker-XS for accelerated performance
+dev-perl/Coro:ev - Build support for using dev-perl/EV as an event-loop via Coro::EV
+dev-perl/Coro:event - Build support for using dev-perl/Event as an event-loop via Coro::Event
+dev-perl/DBD-SQLite:system-sqlite - Use the system-wide dev-db/sqlite installation
+dev-perl/DBD-mysql:embedded - Support embedded server (libmysqld)
+dev-perl/DBD-mysql:ssl - Compile in support for SSL connections via libmysqlclient
+dev-perl/DBIx-Class:admin - Modules required for the DBIx::Class administrative library
+dev-perl/DBIx-Class:admin_script - Modules required for the CLI DBIx::Class interface dbicadmin
+dev-perl/DBIx-Class:deploy - Modules required for "deploy" in DBIx::Class::Storage::DBI and "deploymen_statements" in DBIx::Class::Storage::DBI
+dev-perl/DBIx-Class:replicated - Modules required for DBIx::Class::Storage::DBI::Replicated
+dev-perl/File-HomeDir:xdg - Ensure XDG Semantics for returned paths via x11-misc/xdg-user-dirs
+dev-perl/File-Which:pwhich - Install dev-perl/App-pwhich which used to be a part of this package
+dev-perl/GD:animgif - Enable animated gif support
+dev-perl/GD:fcgi - Build for FastCGI compatibility via dev-libs/fcgi instead of using PerlIO
+dev-perl/Graphics-ColorNames:recommended - Install recommended support modules
+dev-perl/HTML-Mason:modperl - Enable www-apache/mod_perl support
+dev-perl/HTTP-Entity-Parser:xs - Install C-Based dependieces for faster performance
+dev-perl/JSON:xs - Install C-based dev-perl/JSON-XS for faster performance
+dev-perl/JSON-MaybeXS:xs - Install a C-Based backend to make JSON encode/decode fast
+dev-perl/Lab-VXI11:libtirpc - Build against net-libs/libtirpc for RPC support
+dev-perl/List-MoreUtils:xs - Install C-Based backend implementation for performance
+dev-perl/MCE:sereal - Install dev-perl/Sereal-Encoder and decoder for faster worker IPC
+dev-perl/Mail-IMAPClient:md5 - Install support for DIGEST-MD5 and CRAM-MD5 Authentication
+dev-perl/Mail-IMAPClient:ntlm - Install support for NTLM Authentication
+dev-perl/Mail-IMAPClient:ssl - Install support for SSL Connections
+dev-perl/Mail-IMAPClient:zlib - Install support for COMPRESS DEFLATE connections
+dev-perl/Net-OpenSSH:sftp - Enable SFTP protocol support.
+dev-perl/Net-SSH2:gcrypt - Use libgcrypt instead of openssl
+dev-perl/PDL:badval - Enable bad values support
+dev-perl/PDL:hdf - Enable HDF (version 4) format support
+dev-perl/PDL:netpbm - Enable NETPBM and MPEG support
+dev-perl/PDL:pdl2 - Build pdf2 shell (requires Devel-REPL)
+dev-perl/PDL:pgplot - Enable PGPLOT plotting capabilities
+dev-perl/Panotools-Script:gui - Installs GUIs for some tools
+dev-perl/Ref-Util:xs - Install C-Based dev-perl/Ref-Util-XS for accelerated performance
+dev-perl/Sub-Name:suggested - Install extra dependencies needed for extended regression tests
+dev-perl/Sysadm-Install:hammer - Enable hammer() funtion to run a command in the shell and simulate a user hammering the ENTER key to accept defaults on prompts
+dev-perl/Test-Warnings:suggested - Install optional dependencies for extra tests
+dev-perl/Text-CSV:xs - Install dev-perl/Text-CSV_XS for accelerated decoding
+dev-perl/WWW-Form-UrlEncoded:xs - Install C-Based dependieces for faster performance
+dev-perl/perl-headers:debug - Add source locations in generated .ph files to assist with debugging when errors occur
+dev-perl/perl-headers:sizeof-warning - Include logic to warn when a .ph file tries to use a sizeof() that is unknown
+dev-php/PEAR-HTTP_Request2:curl - Force dev-lang/php to be compiled with curl extension
+dev-php/PEAR-HTTP_Request2:fileinfo - Force dev-lang/php to be compiled with fileinfo extension
+dev-php/PEAR-HTTP_Request2:ssl - Force dev-lang/php to be compiled with ssl extension
+dev-php/PEAR-HTTP_Request2:zlib - Force dev-lang/php to be compiled with zlib extension
+dev-php/PEAR-PHP_Beautifier:cli - Require dev-lang/php to be built with the "cli" SAPI and install the php_beautifier script.
+dev-php/ZendFramework:cli - Enables the CLI
+dev-php/ZendFramework:doc - Installs the documentation
+dev-php/ZendFramework:examples - Installs the examples
+dev-php/ZendFramework:minimal - Installs the minimal version without Dojo toolkit, tests and demos
+dev-php/agavi:executable - Install the "agavi" executable used to manage projects. This requires dev-php/phing, and may be omitted if you are (for example) deploying an existing site to a production server.
+dev-php/maxmind-db-reader:extension - Build the C extension that uses dev-libs/libmaxminddb
+dev-php/pecl-apcu:lock_pthreadmutex - Enable pthread mutex locking
+dev-php/pecl-apcu:lock_pthreadrw - Enable pthread read/write locking
+dev-php/pecl-apcu:lock_semaphore - Enable semaphore locks instead of fcntl
+dev-php/pecl-apcu:lock_spinlock - Enable spin locks (EXPERIMENTAL)
+dev-php/pecl-event:extra - Add support of the Libevent extra API
+dev-php/pecl-memcached:igbinary - Enable support for the igbinary serializer
+dev-php/pecl-memcached:json - Enable support for json serialization
+dev-php/pecl-mysqlnd_qc:memcached - Use dev-libs/libmemcached as a storage handler
+dev-php/pecl-mysqlnd_qc:sqlite - Use dev-db/sqlite as a storage handler
+dev-php/pecl-redis:igbinary - Enables igbinary serialisation support
+dev-php/pecl-zmq:czmq - Use the czmq high level bindings
+dev-php/phing:zip - Support zip archives by requiring said support in dev-lang/php.
+dev-php/twig:extension - Build the C extension (only for php-5.6.x).
+dev-php/xcache:coverage - Enable the coverager module (not recommended for production servers).
+dev-python/Kivy:camera - Install libraries needed to support camera
+dev-python/Kivy:garden - Install garden tool to manage user maintained widgets
+dev-python/PyFoam:extras - Enable optional dependencies
+dev-python/PyQt4:X - Build bindings for the QtGui module
+dev-python/PyQt4:compat - Install the deprecated pyqtconfig module for backward compatibility
+dev-python/PyQt4:dbus - Build bindings for the QtDBus module
+dev-python/PyQt4:declarative - Build bindings for the QtDeclarative module
+dev-python/PyQt4:designer - Build bindings for the QtDesigner module and enable the designer plugin
+dev-python/PyQt4:help - Build bindings for the QtHelp module
+dev-python/PyQt4:multimedia - Build bindings for the QtMultimedia module
+dev-python/PyQt4:opengl - Build bindings for the QtOpenGL module
+dev-python/PyQt4:phonon - Build bindings for the phonon module
+dev-python/PyQt4:script - Build bindings for the QtScript module
+dev-python/PyQt4:scripttools - Build bindings for the QtScriptTools module
+dev-python/PyQt4:sql - Build bindings for the QtSql module
+dev-python/PyQt4:svg - Build bindings for the QtSvg module
+dev-python/PyQt4:testlib - Build bindings for the QtTest module
+dev-python/PyQt4:webkit - Build bindings for the QtWebKit module
+dev-python/PyQt4:xmlpatterns - Build bindings for the QtXmlPatterns module
+dev-python/PyQt5:bluetooth - Build bindings for the QtBluetooth module
+dev-python/PyQt5:dbus - Build bindings for the QtDBus module
+dev-python/PyQt5:declarative - Build bindings for the QtQml/QtQuick modules and enable the qmlscene plugin
+dev-python/PyQt5:designer - Build bindings for the QtDesigner module and enable the designer plugin
+dev-python/PyQt5:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-python/PyQt5:gui - Build bindings for the QtGui module
+dev-python/PyQt5:help - Build bindings for the QtHelp module
+dev-python/PyQt5:location - Build bindings for the QtLocation module
+dev-python/PyQt5:multimedia - Build bindings for the QtMultimedia module
+dev-python/PyQt5:network - Build bindings for the QtNetwork module
+dev-python/PyQt5:opengl - Build bindings for the QtOpenGL module
+dev-python/PyQt5:positioning - Build bindings for the QtPositioning module
+dev-python/PyQt5:printsupport - Build bindings for the QtPrintSupport module
+dev-python/PyQt5:sensors - Build bindings for the QtSensors module
+dev-python/PyQt5:serialport - Build bindings for the QtSerialPort module
+dev-python/PyQt5:sql - Build bindings for the QtSql module
+dev-python/PyQt5:svg - Build bindings for the QtSvg module
+dev-python/PyQt5:testlib - Build bindings for the QtTest module
+dev-python/PyQt5:webchannel - Build bindings for the QtWebChannel module
+dev-python/PyQt5:webengine - Build bindings for the QtWebEngine module
+dev-python/PyQt5:webkit - Build bindings for the QtWebKit module
+dev-python/PyQt5:websockets - Build bindings for the QtWebSockets module
+dev-python/PyQt5:widgets - Build bindings for the QtWidgets module
+dev-python/PyQt5:x11extras - Build bindings for the QtX11Extras module
+dev-python/PyQt5:xmlpatterns - Build bindings for the QtXmlPatterns module
+dev-python/PythonQt:extensions - Install extensions
+dev-python/QtPy:designer - Build bindings for the QtDesigner module and enable the designer plugin
+dev-python/QtPy:gui - Build bindings for the QtGui module
+dev-python/QtPy:pyqt5 - Enable the dev-python/PyQt5 backend
+dev-python/QtPy:pyside - Enable the dev-python/pyside backend
+dev-python/QtPy:svg - Build bindings for the QtSvg module
+dev-python/QtPy:testlib - Build bindings for the QtTest module
+dev-python/QtPy:webkit - Build bindings for the QtWebKit module
+dev-python/amqplib:extras - Install extra tools to generate initial Python mod from an AMQP XML file
+dev-python/anyvc:bazaar - Add support for Bazaar
+dev-python/anyvc:mercurial - Add support for Mercurial
+dev-python/celery:redis - Enables redis support
+dev-python/celery:sqs - Enables Amazon SQS transport module for celery
+dev-python/celery:yaml - Enable support of yaml as a configuration file format
+dev-python/celery:zeromq - Enable logging and deployment via ZeroMQ
+dev-python/cgkit:3ds - Enable support for importing 3D Studio models
+dev-python/cvxopt:dsdp - Use interior point library sci-libs/dsdp
+dev-python/cvxopt:glpk - Use GNU Linear Programming Kit sci-mathematics/glpk
+dev-python/dap:server - Enable OpenDAP server support
+dev-python/dask:distributed - Add support for distributed computing with dev-python/distributed
+dev-python/django-cms:admin-style - Install plugin customizing admin panel styles
+dev-python/django-cms:ckeditor - Install text-ckeditor plugin for rich text editing
+dev-python/django-cms:file - Install djangocms file plugin
+dev-python/django-cms:flash - Install djangocms flash plugin
+dev-python/django-cms:inherit - Install djangocms inherit plugin
+dev-python/django-cms:link - Install djangocms link plugin
+dev-python/django-cms:picture - Install djangocms picture plugin
+dev-python/django-cms:snippet - Install djangocms snippet plugin
+dev-python/django-cms:teaser - Install djangocms teaser plugin
+dev-python/django-cms:video - Install djangocms video plugin
+dev-python/django-tastypie:bip - An optional serialiser dev-python/biplist
+dev-python/django-tastypie:digest - Library to aid in implementing HTTP Digest Authentication
+dev-python/django-tastypie:lxml - An optional serialiser dev-python/lxml
+dev-python/django-tastypie:yaml - An optional serialiser dev-python/yaml
+dev-python/django-two-factor-auth:yubikey - Adds support for Yubikeys via django-otp-yubikey
+dev-python/editorconfig-core-py:cli - Install command line interface as well as python library
+dev-python/falcon:cython - Build cython-based python modules
+dev-python/fastparquet:brotli - Enable support for brotli compression
+dev-python/fastparquet:snappy - Enable support for snappy compression
+dev-python/flask-restful:paging - Enable resource paging support
+dev-python/geopy:timezone - Enables localized date support
+dev-python/geopy:yahoo - Enables use of YahooPlaceFinder
+dev-python/glance_store:cinder - enable cinder backend supprt
+dev-python/glance_store:swift - enable swift backend supprt
+dev-python/glance_store:vmware - enable vmware backend supprt
+dev-python/gmpy:mpir - Use sci-libs/mpir as gmp implementation
+dev-python/icalendar:doc - Generate examples and other extra documentation
+dev-python/ipython:matplotlib - Add support for dev-python/matplotlib
+dev-python/ipython:mongodb - Enable support for MongoDB via dev-python/pymongo
+dev-python/ipython:nbconvert - Enable support for converting notebooks to various formats using app-text/pandoc
+dev-python/ipython:notebook - Install requirements for the web notebook based on www-servers/tornado
+dev-python/ipython:octave - Enable octave bridge via dev-python/oct2py
+dev-python/jira:filemagic - Include filemagic support (for identifying uploaded filetypes)
+dev-python/jira:ipython - Include Interactive Python (IPython)
+dev-python/jira:oauth - Support OAuth authentication
+dev-python/kaa-base:tls - SSL/TLS support via dev-python/tlslite
+dev-python/kafka-python:snappy - Install snappy compression/decompression support
+dev-python/kazoo:gevent - Enable support for the gevent based handler
+dev-python/kombu:amqplib - Enable amqplib support
+dev-python/kombu:mongodb - Enables MongoDB backend
+dev-python/kombu:msgpack - Enables MessagePack (de)serializer for Python
+dev-python/kombu:redis - Enables Redis backend
+dev-python/kombu:sqs - Enables Amazon SQS transport module for Kombu
+dev-python/kombu:yaml - Enables yaml backend
+dev-python/markdown:pygments - Enable fancy pygments support
+dev-python/matplotlib:excel - Pull dev-python/xlwt for the exceltools toolkit
+dev-python/matplotlib:gtk2 - Enable x11-libs/gtk+:2 support
+dev-python/matplotlib:gtk3 - Enable x11-libs/gtk+:3 support
+dev-python/matplotlib:pyside - Qt support via dev-python/pyside
+dev-python/mpmath:matplotlib - Add support for dev-python/matplotlib
+dev-python/msgpack:native-extensions - Compiles native "C" extensions (speedups, instead of using python fallback code).
+dev-python/nbdime:webtools - Install web-based diff and merge tools.
+dev-python/netaddr:cli - Enable netaddr shell with dev-python/ipython
+dev-python/networkx:scipy - Enables scipy backend
+dev-python/nltk:numpy - Use numpy for the saved word tokenizer
+dev-python/numexpr:mkl - Enable support for Intel Vector Math Library, part of sci-libs/mkl.
+dev-python/pandas:R - Enable support for R via dev-python/rpy
+dev-python/pandas:excel - Pull a few Python packages for Microsoft Excel i/o
+dev-python/pandas:full-support - Pull all packages to give pandas full support
+dev-python/pandas:html - Enable HTML i/o via dev-python/beautifulsoup
+dev-python/passlib:bcrypt - bcrpyt hash algoryptm support
+dev-python/passlib:scrypt - accelerated scrypt algoythm support
+dev-python/passlib:totp - time based one time password support
+dev-python/paste:flup - enable support for flup (and therefore for various wgsi servers and middleware)
+dev-python/paste:openid - enable OpenID support
+dev-python/pillow:imagequant - Build with Image Quantization Library support
+dev-python/py-amqp:extras - Install extra tools to generate initial Python mod from an AMQP XML file
+dev-python/pygame:midi - Enable midi support using media-libs/portmidi
+dev-python/pygpu:cuda - Enable NVIDIA CUDA toolkit support
+dev-python/pygpu:opencl - Enable OpenCL support
+dev-python/pyilmbase:numpy - Add bindings for dev-python/numpy use.
+dev-python/pyocr:cuneiform - Enable support for the app-text/cuneiform OCR engine
+dev-python/pyocr:tesseract - Enable support for the app-text/tesseract OCR engine
+dev-python/pypax:ptpax - Enable PT_PAX_FLAGS support.
+dev-python/pypax:xtpax - Enable XATTR_PAX_FLAGS support.
+dev-python/pyplusplus:indexing - Install indexing_suite_v2 to enhance boost python
+dev-python/pyplusplus:numpy - Generate code for dev-libs/boost-numpy to accelerate arrays
+dev-python/pypy:low-memory - Build using PyPy with the engine configured towards low memory footprint. This makes it possible to build PyPy using ~3.5G of RAM on amd64 and ~half of that on x86, at the cost of lengthened build time.
+dev-python/pypy:sandbox - Enable sandboxing functionality
+dev-python/pypy3:low-memory - Build using PyPy with the engine configured towards low memory footprint. This makes it possible to build PyPy using ~3.5G of RAM on amd64 and ~half of that on x86, at the cost of lengthened build time.
+dev-python/pypy3:sandbox - Enable sandboxing functionality
+dev-python/pyside:X - Build QtGui and QtTest modules
+dev-python/pyside:declarative - Build QtDeclarative module
+dev-python/pyside:designer - Build QtDesigner and QtUiTools modules
+dev-python/pyside:help - Build QtHelp module
+dev-python/pyside:multimedia - Build QtMultimedia module
+dev-python/pyside:opengl - Build QtOpenGL module
+dev-python/pyside:phonon - Build phonon module
+dev-python/pyside:script - Build QtScript module
+dev-python/pyside:scripttools - Build QtScriptTools module
+dev-python/pyside:sql - Build QtSql module
+dev-python/pyside:svg - Build QtSvg module
+dev-python/pyside:webkit - Build QtWebKit module
+dev-python/pyside:xmlpatterns - Build QtXmlPatterns module
+dev-python/python-caja:gtk3 - Build with GTK+3 instead of GTK+2
+dev-python/python-stdnum:vies - Enable VIES
+dev-python/pyudev:pygobject - Install PyGobject bindings
+dev-python/pyudev:pyside - Install PySide bindings
+dev-python/pyudev:qt4 - Install PyQt4 bindings
+dev-python/pyudev:qt5 - Install PyQt5 bindings
+dev-python/pyyaml:libyaml - enable support for C implementation using libyaml
+dev-python/pyzor:gevent - Enable support for the gevent based handler
+dev-python/pyzor:mysql - Enables mysql support
+dev-python/pyzor:pyzord - enable support for pyzord
+dev-python/pyzor:redis - Enables redis support
+dev-python/rarfile:compressed - Enables the module to support compressed v3 archives by calling the app-arch/unrar.
+dev-python/rdflib:redland - enable support for Redland triplestore
+dev-python/restkit:cli - Install the restcli command line interface/tool, based on dev-python/ipython
+dev-python/scrapy:boto - Add support for Amazon S3 via dev-python/boto
+dev-python/scrapy:ibl - Use Instace Based Learning algorithm for automatic extraction
+dev-python/setuptools_scm:mercurial - Enables mercurial backend
+dev-python/simplecv:shell - Enable the iPython SimpleCV shell
+dev-python/simplespectral:faster - Use sci-libs/scipy to speed up drawing
+dev-python/simplespectral:fastest - Use dev-python/pyFFTW to speed up drawing to the max
+dev-python/sphinx:net - enable internet capabilities
+dev-python/sympy:imaging - Add support for dev-python/pillow
+dev-python/sympy:ipython - Add support for dev-python/ipython
+dev-python/sympy:mathml - Add support for mathml
+dev-python/sympy:pyglet - Use dev-python/pyglet for plots and print preview
+dev-python/sympy:symengine - Add support for a dev-python/symengine backend
+dev-python/sympy:texmacs - Add app-office/texmacs interface
+dev-python/sympy:theano - Add support for dev-python/theano
+dev-python/tdaemon:coverage - Enable code coverage support
+dev-python/translate-toolkit:html - Support conversion between po and html files
+dev-python/translate-toolkit:ical - Support conversion between po and ical files
+dev-python/translate-toolkit:ini - Support conversion between po and ini files
+dev-python/translate-toolkit:subtitles - Support conversion between po and sub files
+dev-python/translate-toolkit:yaml - Support YAML format
+dev-python/twisted:conch - include Twisted SSHv2 implementation
+dev-python/twisted:http2 - include http2 support
+dev-python/twisted:serial - include serial port support
+dev-python/twisted-core:serial - include serial port support
+dev-python/vatnumber:vies - Enable VIES
+dev-python/ws4py:client - Install client modules
+dev-python/ws4py:server - Install server modules
+dev-python/wxpython:doc - Install HTML wxWidgets docs and wxpython API reference.
+dev-python/wxpython:examples - Install interactive demo module browser and sample applets.
+dev-python/zeep:async - Add async support
+dev-python/zeep:tornado - Add tornado support
+dev-python/zsi:twisted - add support for python-twisted (needs dev-python/twisted-core and dev-python/twisted-web)
+dev-qt/assistant:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/designer:declarative - Build the qdeclarativeview plugin
+dev-qt/designer:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/designer:phonon - Build the phononwidgets plugin
+dev-qt/designer:qt3support - Build the qt3supportwidgets plugin
+dev-qt/designer:webkit - Build the qwebview plugin
+dev-qt/linguist:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/linguist-tools:qml - Enable QML support in lupdate
+dev-qt/pixeltool:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qdbusviewer:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qdoc:qml - Enable QML/JS parsing support
+dev-qt/qt-creator:android - Build plugin for Android devices
+dev-qt/qt-creator:autotools - Enable autotools project manager plugin
+dev-qt/qt-creator:baremetal - Build plugin for bare metal devices
+dev-qt/qt-creator:bazaar - Add support for dev-vcs/bzr version control system
+dev-qt/qt-creator:clangcodemodel - Build clang-based code model and refactoring plugins
+dev-qt/qt-creator:clangstaticanalyzer - Build clang-based static analyzer plugin
+dev-qt/qt-creator:clearcase - Add support for IBM ClearCase version control system (requires manual installation of ClearCase client)
+dev-qt/qt-creator:cmake - Enable cmake project manager plugin
+dev-qt/qt-creator:designer - Build widget designer plugin
+dev-qt/qt-creator:glsl - Enable GLSL source code editor
+dev-qt/qt-creator:ios - Build plugin for Apple iOS devices
+dev-qt/qt-creator:mercurial - Add support for dev-vcs/mercurial version control system
+dev-qt/qt-creator:modeling - Enable graphical model editor
+dev-qt/qt-creator:nim - Enable Nim source code editor
+dev-qt/qt-creator:perforce - Add support for Perforce version control system (requires manual installation of Perforce client)
+dev-qt/qt-creator:python - Enable Python source code editor
+dev-qt/qt-creator:qbs - Enable QBS project manager plugin
+dev-qt/qt-creator:qnx - Build plugin for QNX devices
+dev-qt/qt-creator:scxml - Enable graphical SCXML editor
+dev-qt/qt-creator:systemd - Add support for retrieving application output from journald
+dev-qt/qt-creator:valgrind - Add support for memory debugging using dev-util/valgrind
+dev-qt/qt-creator:webengine - Use dev-qt/qtwebengine to view documentation
+dev-qt/qt-creator:winrt - Build plugin for WinRT devices
+dev-qt/qt-docs:charts - Install documentation for dev-qt/qtcharts
+dev-qt/qt-docs:datavis - Install documentation for dev-qt/qtdatavis3d
+dev-qt/qt-docs:networkauth - Install documentation for dev-qt/qtnetworkauth
+dev-qt/qt-docs:script - Install documentation for dev-qt/qtscript
+dev-qt/qt-docs:speech - Install documentation for dev-qt/qtspeech
+dev-qt/qt-docs:virtualkeyboard - Install documentation for dev-qt/qtvirtualkeyboard
+dev-qt/qt-docs:webengine - Install documentation for dev-qt/qtwebengine
+dev-qt/qt-meta:qt3support - Enable the Qt3Support library for Qt4
+dev-qt/qt3d:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qt3d:qml - Build QML/QtQuick bindings
+dev-qt/qt3support:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtbearer:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtbluetooth:qml - Build QML/QtQuick bindings and imports
+dev-qt/qtcharts:qml - Build QML/QtQuick bindings and imports
+dev-qt/qtcore:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtcore:glib - Enable dev-libs/glib eventloop support
+dev-qt/qtcore:qt3support - Enable the Qt3Support libraries for Qt4. Note that this does not mean you can compile pure Qt3 programs with Qt4.
+dev-qt/qtcore:systemd - Enable native journald logging support
+dev-qt/qtdatavis3d:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtdatavis3d:qml - Build QML/QtQuick bindings and imports
+dev-qt/qtdbus:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtdeclarative:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtdeclarative:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtdeclarative:localstorage - Build the LocalStorage import for QtQuick (requires QtSql)
+dev-qt/qtdeclarative:qt3support - Enable the Qt3Support libraries for Qt4. Note that this does not mean you can compile pure Qt3 programs with Qt4.
+dev-qt/qtdeclarative:webkit - Build the WebView QML component
+dev-qt/qtdeclarative:widgets - Enable QtWidgets support
+dev-qt/qtdeclarative:xml - Build the XmlListModel import for QtQuick (requires QtXmlPatterns)
+dev-qt/qtdemo:dbus - Build QtDBus examples and demos
+dev-qt/qtdemo:declarative - Build QtDeclarative examples and demos
+dev-qt/qtdemo:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtdemo:multimedia - Build QtMultimedia examples and demos
+dev-qt/qtdemo:opengl - Build QtOpenGL examples and demos
+dev-qt/qtdemo:phonon - Build Phonon examples and demos
+dev-qt/qtdemo:webkit - Build QtWebKit examples and demos
+dev-qt/qtdemo:xmlpatterns - Build QtXmlPatterns examples and demos
+dev-qt/qtdiag:network - Report network information
+dev-qt/qtdiag:widgets - Report widget style information
+dev-qt/qtgui:egl - Enable EGL integration
+dev-qt/qtgui:eglfs - Build the EGL Full Screen/Single Surface platform plugin
+dev-qt/qtgui:evdev - Enable support for input devices via evdev
+dev-qt/qtgui:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtgui:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtgui:glib - Enable integration with the dev-libs/glib event loop
+dev-qt/qtgui:gtkstyle - Build a widgets style that mimics the active GTK+ theme
+dev-qt/qtgui:ibus - Build the IBus input method plugin
+dev-qt/qtgui:libinput - Enable support for input devices via dev-libs/libinput
+dev-qt/qtgui:qt3support - Enable the Qt3Support libraries for Qt4. Note that this does not mean you can compile pure Qt3 programs with Qt4.
+dev-qt/qtgui:trace - Build the 'trace' graphicssystem engine which allows to record all drawing operations into a trace buffer. The trace can be replayed later with the qttracereplay tool.
+dev-qt/qtgui:tslib - Enable support for touchscreen devices via x11-libs/tslib
+dev-qt/qtgui:tuio - Build plugin to receive touch events over the TUIO protocol
+dev-qt/qtgui:xcb - Build the XCB platform plugin and enable X11 integration
+dev-qt/qthelp:compat - Build the extra compatibility layer required by a few packages, see http://blog.qt.io/blog/2010/06/22/qt-assistant-compat-version-available-as-extra-source-package/
+dev-qt/qthelp:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtmultimedia:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtmultimedia:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtmultimedia:gstreamer - Enable audio support via media-libs/gstreamer using SLOT 1.0
+dev-qt/qtmultimedia:qml - Build QML/QtQuick bindings and imports
+dev-qt/qtmultimedia:widgets - Build the QtMultimediaWidgets module
+dev-qt/qtnetwork:bindist - Disable EC support via dev-libs/openssl
+dev-qt/qtnetwork:connman - Enable net-misc/connman-based bearer plugin
+dev-qt/qtnetwork:libproxy - Use net-libs/libproxy for automatic HTTP/SOCKS proxy configuration
+dev-qt/qtnetwork:networkmanager - Enable net-misc/networkmanager-based bearer plugin
+dev-qt/qtopengl:egl - Use EGL instead of GLX to manage OpenGL contexts
+dev-qt/qtopengl:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtopengl:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtopengl:qt3support - Enable the Qt3Support libraries for Qt4
+dev-qt/qtpositioning:geoclue - Use enhanced location information from app-misc/geoclue
+dev-qt/qtpositioning:qml - Build QML bindings
+dev-qt/qtprintsupport:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtquickcontrols:widgets - Enable QtWidgets support
+dev-qt/qtquickcontrols2:widgets - Enable QtWidgets support
+dev-qt/qtscript:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtscript:scripttools - Build the QtScriptTools module (requires QtWidgets)
+dev-qt/qtsensors:qml - Build QML bindings
+dev-qt/qtsql:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtsql:qt3support - Enable the Qt3Support libraries for Qt4
+dev-qt/qtsvg:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qttest:exceptions - Add support for exceptions - like catching them inside the event loop (recommended by upstream)
+dev-qt/qtvirtualkeyboard:handwriting - Adds handwriting recognition integration support
+dev-qt/qtwayland:libinput - Enable support for input devices via dev-libs/libinput
+dev-qt/qtwebchannel:qml - Build QML/QtQuick bindings and imports
+dev-qt/qtwebengine:geolocation - Enable physical position determination via dev-qt/qtpositioning
+dev-qt/qtwebengine:pax_kernel - Enable building under a PaX enabled kernel
+dev-qt/qtwebengine:system-ffmpeg - Use the system-wide media-video/ffmpeg instead of bundled.
+dev-qt/qtwebengine:system-icu - Use the system-wide dev-libs/icu instead of bundled.
+dev-qt/qtwebengine:widgets - Enable QtWidgets support
+dev-qt/qtwebkit:geolocation - Enable physical position determination via dev-qt/qtpositioning
+dev-qt/qtwebkit:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-qt/qtwebkit:gstreamer - Enable HTML5 audio/video support via media-libs/gstreamer using SLOT 1.0
+dev-qt/qtwebkit:gstreamer010 - Enable HTML5 audio/video support via media-libs/gstreamer using SLOT 0.10
+dev-qt/qtwebkit:multimedia - Enable HTML5 audio/video support via dev-qt/qtmultimedia
+dev-qt/qtwebkit:orientation - Enable device orientation detection via dev-qt/qtsensors
+dev-qt/qtwebkit:printsupport - Enable printing via dev-qt/qtprintsupport
+dev-qt/qtwebkit:qml - Build QML/QtQuick bindings
+dev-qt/qtwebkit:webchannel - Enable integration with dev-qt/qtwebchannel
+dev-qt/qtwebkit:webp - Add support for WebP image format
+dev-qt/qtwebsockets:qml - Build QML bindings
+dev-qt/qtwidgets:gles2 - Use GLES 2.0 or later instead of full OpenGL
+dev-ros/rosbag:lz4 - Add support for lz4 compressed bags.
+dev-ros/rosconsole:glog - Use dev-cpp/glog as log backend.
+dev-ros/rosconsole:log4cxx - Use dev-libs/log4cxx as log backend.
+dev-ruby/barby:cairo - Add support for writing images (PNG, PS, EPS and, if supported, PDF and SVG) using dev-ruby/rcairo. Not available on JRuby.
+dev-ruby/barby:png - Add support for writing PNG images using dev-ruby/chunky_png.
+dev-ruby/barby:prawn - Add support for writing PDF documents using dev-ruby/prawn.
+dev-ruby/barby:qrcode - Add support for QRCode 2D codes using dev-ruby/rqrcode.
+dev-ruby/barby:rmagick - Add support for writing images (among others PNG, GIF and JPEG) using dev-ruby/rmagick. Not available on JRuby.
+dev-ruby/facter:dmi - Use sys-apps/dmidecode to determine hardware system properties
+dev-ruby/facter:pciutils - Use sys-apps/pciutils to determine hardware system properties
+dev-ruby/facter:virt - Use app-emulation/virt-what for virtual machine detection
+dev-ruby/faraday_middleware:mashify - Include FaradayMiddleware::Mashify
+dev-ruby/faraday_middleware:oauth - Include FaradayMiddleware::OAuth
+dev-ruby/faraday_middleware:parsexml - Include FaradayMiddleware::ParseXml
+dev-ruby/faraday_middleware:rashify - Include FaradayMiddleware::Rashify
+dev-ruby/maruku:highlight - Enable source code highlighting via dev-ruby/syntax
+dev-ruby/net-ssh:sodium - Use dev-libs/libsodium via dev-ruby/rbnacl for Ed25519 support
+dev-ruby/rails:asset-pipeline - Also install the default components for the asset pipeline. These are not required but they are activated automatically in new Rails projects by default.
+dev-ruby/rrdtool-bindings:graph - Enable support for graphing functions
+dev-ruby/rspec-core:highlight - Enable source code highlighting via dev-ruby/coderay
+dev-ruby/ruby-sdl:image - Enable media-libs/sdl-image support
+dev-ruby/ruby-sdl:mixer - Enable media-libs/sdl-mixer support
+dev-ruby/ruby-sdl:sge - Enable sdl-sge support
+dev-ruby/rubygems:server - Install support for the rubygems server
+dev-scheme/gauche-gl:cg - Enable NVidia Cg binding
+dev-scheme/gauche-gtk:glgd - Enable GL graph draw
+dev-scheme/guile:debug-freelist - Include garbage collector freelist debugging code
+dev-scheme/guile:debug-malloc - Include malloc debugging code
+dev-scheme/guile:deprecated - Enable deprecated features
+dev-scheme/guile:discouraged - (implied by deprecated) enable merely discouraged features
+dev-scheme/guile:networking - Include networking interfaces
+dev-scheme/guile:regex - Include regular expression interfaces
+dev-scheme/kawa:awt - Assume AWT is available
+dev-scheme/kawa:echo2 - Enable support for the Echo2 web toolkit with dev-java/echo2
+dev-scheme/kawa:frontend - Build "kawa" front-end program using sys-libs/readline
+dev-scheme/kawa:jemacs - Build JEmacs
+dev-scheme/kawa:krl - Build BRL emulation and KRL
+dev-scheme/kawa:sax - Assume SAX2 is available with dev-java/sax
+dev-scheme/kawa:servlets - Build support for generating servlets with dev-java/servletapi
+dev-scheme/kawa:swing - Assume Swing is available
+dev-scheme/kawa:xqtests - Support XQuery Test Suite
+dev-scheme/racket:futures - Enable racket/future library for fine-grained hardware parallelism
+dev-scheme/racket:places - Enable racket/place library for share-nothing parallelism and message-passing communication. Compared to futures, places are heavyweight, but they have a simpler performance model.
+dev-scheme/racket:threads - Enable support for green threads
+dev-scheme/scm:arrays - Support for arrays, uniform-arrays and uniform-vectors.
+dev-scheme/scm:bignums - Support for large precision integers.
+dev-scheme/scm:cautious - SCM will always check the number of arguments to interpreted closures.
+dev-scheme/scm:dynamic-linking - Be able to load compiled files while running.
+dev-scheme/scm:engineering-notation - Floats to display in engineering notation (exponents always multiples of 3) instead of scientific notation.
+dev-scheme/scm:gsubr - generalized c arguments: for arbitrary (more then 11) arguments to C functions.
+dev-scheme/scm:inexact - Support for floating point numbers.
+dev-scheme/scm:ioext - Commonly available I/O extensions: line I/O, file positioning, file delete and rename, and directory functions.
+dev-scheme/scm:libscm - Build and install libscm.a and related headers
+dev-scheme/scm:macro - C level support for hygienic and referentially transparent macros (syntax-rules macros).
+dev-scheme/scm:regex - String regular expression matching.
+dev-scheme/scm:unix - Support for: nice, acct, lstat, readlink, symlink, mknod and sync.
+dev-scheme/slib:gambit - Support for gambit scheme implementation
+dev-scheme/slib:scm - Support for scm scheme implementation
+dev-tcltk/expect-lite:debug - pull in packages needed for runtime interactive debugger
+dev-tcltk/tktreectrl:shellicon - shellicon extension
+dev-tex/abntex:lyx - Install with app-office/lyx layout
+dev-tex/biblatex:biber - Install the unicode compatible backend processor
+dev-tex/circuit_macros:script - Install cm2pdf to automatically create a correctly sized PDF from a circuit_macro m4 source
+dev-tex/dot2texi:pgf - Enable support for dev-tex/pgf (The TeX Portable Graphic Format)
+dev-tex/dot2texi:pstricks - Enable pstricks support
+dev-tex/pythontex:highlighting - Syntax highlighting using dev-python/pygments
+dev-texlive/texlive-basic:luajittex - Add support for LuaJitTeX: LuaTeX based on LuaJIT which is usually faster.
+dev-util/android-ndk:legacy-toolchains - Install legacy toolchains
+dev-util/android-ndk:target-32 - Support for 32-bit targets
+dev-util/android-ndk:target-64 - Support for 64-bit targets
+dev-util/anjuta:devhelp - Enable devhelp integration
+dev-util/anjuta:glade - Build glade plugin for anjuta
+dev-util/anjuta:packagekit - Use packagekit to search for missing tools
+dev-util/anjuta:terminal - Enable terminal plugin based on x11-libs/vte
+dev-util/apitrace:cli - Enable command line interface
+dev-util/apitrace:egl - Enable EGL support
+dev-util/apitrace:system-snappy - Link dynamic against app-arch/snappy
+dev-util/bazel:tools - Install extra bazel tools to build from sources
+dev-util/bitcoin-tx:knots - Build enhanced Bitcoin Knots version, rather than Bitcoin Core
+dev-util/bitcoin-tx:ljr - Enable Luke Dashjr's patches
+dev-util/buildbot:docker - Add support for worker docker command steps
+dev-util/buildbot:irc - Add support for status delivery through an ircbot.
+dev-util/buildbot:mail - Add support for watching a maildir for commits.
+dev-util/buildbot:manhole - Add support for manhole (debug over ssh)
+dev-util/bustle:interactivetests - Build interactive test programs
+dev-util/bustle:threaded - Build with support for multithreaded execution.
+dev-util/catalyst:ccache - Enables ccache support
+dev-util/cccc:apidoc - Build software docs with doxygen/graphviz and metrics with cccc
+dev-util/cccc:mfc - Add patch for MFC dialect options
+dev-util/cmake:server - Enable cmake-server support.
+dev-util/cmake:system-jsoncpp - Use system copy of dev-libs/jsoncpp instead of bundled one.
+dev-util/coccigrep:vim - Install the coccigrep vim plugin
+dev-util/codeblocks:contrib - Build additional contrib components
+dev-util/cppcheck:htmlreport - install cppcheck-htmlreport
+dev-util/ctags:json - Enable JSON output support
+dev-util/ctags:xml - Enable XML parsing support
+dev-util/ctags:yaml - Enable YAML parsing support
+dev-util/cwdiff:a2ps - install app-text/a2ps for postscript output
+dev-util/cwdiff:mercurial - install hg wdiff alias for dev-vcs/mercurial
+dev-util/devhelp:gedit - Install plugin for app-editors/gedit
+dev-util/dialog:minimal - Disable library, install command-line program only
+dev-util/diffoscope:R - Use dev-lang/R
+dev-util/diffoscope:binutils - Use sys-devel/binutils
+dev-util/diffoscope:colord - Use x11-misc/colord
+dev-util/diffoscope:cpio - Use app-arch/cpio
+dev-util/diffoscope:diff - Use sys-apps/diffutils
+dev-util/diffoscope:docx - Use app-text/docx2txt
+dev-util/diffoscope:dtc - Use sys-apps/dtc
+dev-util/diffoscope:e2fsprogs - Use sys-fs/e2fsprogs
+dev-util/diffoscope:file - Use sys-apps/file
+dev-util/diffoscope:find - Use sys-apps/findutils
+dev-util/diffoscope:gettext - Use sys-devel/gettext
+dev-util/diffoscope:gpg - Use app-crypt/gnupg
+dev-util/diffoscope:haskell - Use dev-lang/ghc
+dev-util/diffoscope:hex - Use app-editors/vim-core
+dev-util/diffoscope:iso - Use virtual/cdrtools
+dev-util/diffoscope:llvm - Use sys-devel/llvm
+dev-util/diffoscope:opendocument - Use app-text/odt2txt
+dev-util/diffoscope:pascal - Use dev-lang/fpc
+dev-util/diffoscope:rpm - Use app-arch/rpm
+dev-util/diffoscope:squashfs - Use sys-fs/squashfs-tools
+dev-util/diffoscope:ssh - Use net-misc/openssh
+dev-util/diffoscope:tar - Use app-arch/tar
+dev-util/diffoscope:tcpdump - Use net-analyzer/tcpdump
+dev-util/diffoscope:xz - Use app-arch/xz-utils
+dev-util/diffoscope:zip - Use app-arch/unzip
+dev-util/edb-debugger:graphviz - Add support for the Graphviz library
+dev-util/edb-debugger:legacy-mem-write - Probe if writes to /proc/PID/mem are broken.
+dev-util/edb-debugger:pax_kernel - Enable building under a PaX enabled kernel
+dev-util/electron:lto - Build with link time optimization enabled
+dev-util/electron:pic - Disable optimized assembly code that is not PIC friendly
+dev-util/electron:proprietary-codecs - Enable proprietary codecs like H.264, MP3
+dev-util/electron:system-ffmpeg - Use system ffmpeg instead of the bundled one
+dev-util/electron:tcmalloc - Use bundled tcmalloc instead of system malloc
+dev-util/emilpro:system-binutils - Use the gentoo binutils instead of building against an unpatched vanilla version
+dev-util/fatrace:powertop - Add powetop integration
+dev-util/geany:gtk3 - Use GTK+3 instead of GTK+2
+dev-util/geany:vte - Enable Terminal support (x11-libs/vte)
+dev-util/geany-plugins:autoclose - Enable the autoclose plugin.
+dev-util/geany-plugins:automark - Enable the automark plugin
+dev-util/geany-plugins:commander - Enable the commander plugin which provides a command panel for rapid access to any action.
+dev-util/geany-plugins:ctags - Enable ctags plugin
+dev-util/geany-plugins:debugger - Enable the debugger plugin which interfaces with sys-devel/gdb
+dev-util/geany-plugins:defineformat - Enable the defineformat plugin.
+dev-util/geany-plugins:enchant - Enable spell checking using enchant
+dev-util/geany-plugins:gpg - Enable geanypg plugin which integrates GPG using app-crypt/gpgme
+dev-util/geany-plugins:gtk3 - Use GTK+3 instead of GTK+2
+dev-util/geany-plugins:gtkspell - Use gtkspell for dictionary support in GeanyVC
+dev-util/geany-plugins:multiterm - Enable the multiterm plugin
+dev-util/geany-plugins:overview - Enable overview plugin
+dev-util/geany-plugins:pretty-printer - Enable pretty-printer plugin
+dev-util/geany-plugins:scope - Enable the scope plugin which is a graphical GDB front-end
+dev-util/geany-plugins:soup - Enable updatechecker and geniuspaste plugins which require net-libs/libsoup
+dev-util/global:vim - Integrate the GNU GLOBAL source code tag system with Vim
+dev-util/google-perftools:debug - Build a set of libraries with debug support (so-called debugalloc). These are available by default but are not needed unless you're actually developing using tcmalloc.
+dev-util/google-perftools:largepages - Use (experimental) larger pages for tcmalloc, this increases memory usage, but should speed up the allocation/free operations.
+dev-util/google-perftools:minimal - Only build the tcmalloc_minimal library, ignoring the heap checker and the profilers.
+dev-util/google-perftools:optimisememory - To build libtcmalloc with smaller internal caches.
+dev-util/gtk-doc:highlight - Enable source code highlighting
+dev-util/gtk-doc:vim - Enable source code highlighting through app-editors/vim
+dev-util/idea-community:custom-jdk - Install and use IntelliJ's custom JRE.
+dev-util/idea-ultimate:custom-jdk - Install and use IntelliJ's custom JRE.
+dev-util/intel-ocl-sdk:android - Install android related files
+dev-util/intel-ocl-sdk:system-boost - Use system boost (dev-libs/boost) instead of bundled one
+dev-util/intel-ocl-sdk:system-clang - Use system clang (sys-devel/clang) instead of bundled one
+dev-util/intel-ocl-sdk:system-qt - Use system Qt (sys-devel-qtcore, sys-devel/qtgui) instead of bundled one
+dev-util/intel-ocl-sdk:system-tbb - Use sytem Thread Building Blocks (dev-cpp/tbb) instead of bundled one
+dev-util/intel-ocl-sdk:tools - Install Intel Offline Compiler
+dev-util/kdevelop:gdbui - Enable GUI for attaching GDB to a running process
+dev-util/kdevelop:okteta - Enable hex editor plugin via kde-apps/okteta
+dev-util/kdevelop:qmake - Enable support for QMake build system
+dev-util/kdevelop:reviewboard - Enable reviewboard support
+dev-util/kdevelop:webkit - Enable deprecated dev-qt/qtwebkit instead of dev-qt/qtwebengine for integrated documentation
+dev-util/kdevelop:welcomepage - Enable welcome page, requires dev-qt/qtdeclarative
+dev-util/ltrace:unwind - Use sys-libs/libunwind for frame unwinding support
+dev-util/lttng-tools:ust - Support LTTng-UST (Userspace Tracing)
+dev-util/massif-visualizer:callgraph - Enable detailed snapshot analysis using media-gfx/kgraphviewer
+dev-util/mdds:valgrind - Add support for memory debugging using dev-util/valgrind
+dev-util/mingw64-runtime:idl - Install idl files.
+dev-util/mingw64-runtime:libraries - Build extra libraries.
+dev-util/mingw64-runtime:tools - Build extra tools.
+dev-util/molecule:plugins - Add plugins provided by dev-util/molecule-plugins
+dev-util/nemiver:memoryview - Enable the optional hexadecimal memory inspection with app-editors/ghex
+dev-util/nvidia-cuda-sdk:cuda - Build CUDA binaries
+dev-util/nvidia-cuda-sdk:opencl - Build OpenCL binaries
+dev-util/nvidia-cuda-toolkit:debugger - Installs the CUDA debugger
+dev-util/nvidia-cuda-toolkit:eclipse - Install plugins for eclipse
+dev-util/nvidia-cuda-toolkit:profiler - Installs the NVIDIA CUDA visual profiler
+dev-util/perf:demangle - Enable C++ symbol name demangling, using libbfd from sys-devel/binutils. When this flag is enabled, the package will have to be rebuilt after every version bump of binutils.
+dev-util/perf:doc - Build documentation and man pages. With this USE flag disabled, the --help parameter for perf and its sub-tools will not be available. This is optional because it depends on a few documentation handling tools that are not always welcome on user systems.
+dev-util/perf:numa - Enable NUMA support
+dev-util/perf:perl - Add support for Perl as a scripting language for perf tools.
+dev-util/perf:unwind - Use sys-libs/libunwind for frame unwinding support.
+dev-util/pkgconf:pkg-config - Install as a replacement for dev-util/pkgconfig
+dev-util/pkgconfig:internal-glib - Use internal copy of dev-libs/glib
+dev-util/pkgconfig-openbsd:pkg-config - Install as a replacement for dev-util/pkgconfig
+dev-util/radare2:system-capstone - Use dev-libs/capstone instead of bundled copy.
+dev-util/scanmem:gui - Enable the GameConqueror GUI
+dev-util/schroot:btrfs - Enable support for chroots using btrfs snapshots.
+dev-util/schroot:dchroot - Enables the building of a wrapper named "dchroot", replacing sys-apps/dchroot.
+dev-util/schroot:lvm - Enable support for chroots using LVM snapshots.
+dev-util/squashdelta:lz4 - Enable support for LZ4 compression using app-arch/lz4
+dev-util/squashmerge:lz4 - Enable support for LZ4 compression using app-arch/lz4
+dev-util/strace:aio - Enable dev-libs/libaio support for tracing Asynchronous I/O operations
+dev-util/strace:unwind - Enable stack backtraces (-k flag) via sys-libs/libunwind
+dev-util/suse-build:symlink - Provide compatibility symlinks with original openSUSE package (might clash with other packages)
+dev-util/sysdig:modules - Build kernel modules needed for tracing local events. Disable this only if you intend to use sysdig purely to work with dumpfiles.
+dev-util/sysprof:systemd - Build the sysprofd daemon service, required to run the UI without root permissions. Relies on sys-apps/systemd running as the init system.
+dev-util/systemtap:libvirt - Support probing of libvirt domains.
+dev-util/trace-cmd:udis86 - Enable support for dev-libs/udis86 disassembler library
+dev-vcs/bzr:sftp - Enable sftp support
+dev-vcs/cssc:valgrind - Enable usage of dev-util/valgrind in tests
+dev-vcs/cvs:server - Enable server support
+dev-vcs/cvs2svn:bazaar - Support for dev-vcs/bzr
+dev-vcs/cvsync:gcrypt - Use dev-libs/libgcrypt for hash functions.
+dev-vcs/cvsync:mhash - Use app-crypt/mhash for hash functions.
+dev-vcs/cvsync:openssl - Use dev-libs/openssl for hash functions.
+dev-vcs/darcs:diff - Use 'lcs' for diff building.
+dev-vcs/darcs:http - Use the pure Haskell HTTP package for HTTP support.
+dev-vcs/darcs:network-uri - Get Network.URI from the network-uri package.
+dev-vcs/darcs:terminfo - Use the terminfo package for enhanced console support.
+dev-vcs/darcs:threaded - Use threading and SMP support.
+dev-vcs/fossil:fusefs - Enable the Fuse Filesystem
+dev-vcs/fossil:json - Enable the JSON API of Fossil's wiki
+dev-vcs/fossil:legacy-mv-rm - Enable legacy behavior for mv/rm (skip checkout files).
+dev-vcs/fossil:miniz - Use the bundled miniz for compression instead of zlib. Incompatible with ssl.
+dev-vcs/fossil:system-sqlite - Use the system SQLite instead of the bundled one
+dev-vcs/fossil:tcl-private-stubs - Enable Tcl integration via private stubs mechanism
+dev-vcs/fossil:tcl-stubs - Enable Tcl integration via stubs library mechanism
+dev-vcs/fossil:th1-docs - Enable TH1 for embedded documentation pages
+dev-vcs/fossil:th1-hooks - Enable TH1 hooks for commands and web pages
+dev-vcs/git:blksha1 - Use the new optimized SHA1 implementation
+dev-vcs/git:cgi - Install gitweb too
+dev-vcs/git:curl - Support fetching and pushing (requires webdav too) over http:// and https:// protocols
+dev-vcs/git:gpg - Pull in gnupg for signing -- without gnupg, attempts at signing will fail at runtime!
+dev-vcs/git:highlight - GitWeb support for app-text/highlight
+dev-vcs/git:mediawiki - Support pulling and pushing from MediaWiki
+dev-vcs/git:mediawiki-experimental - Add experimental patches for improved MediaWiki support
+dev-vcs/git:pcre-jit - Enable JIT for pcre
+dev-vcs/git:ppcsha1 - Make use of a bundled routine that is optimized for the PPC arch
+dev-vcs/git:subversion - Include git-svn for dev-vcs/subversion support
+dev-vcs/git:tk - Include the 'gitk' and 'git gui' tools
+dev-vcs/git:webdav - Adds support for push'ing to HTTP/HTTPS repositories via DAV
+dev-vcs/git-annex:assistant - Enable git-annex assistant and watch command
+dev-vcs/git-annex:benchmark - Enable benchmarking
+dev-vcs/git-annex:concurrentoutput - Use concurrent-output library (experimental)
+dev-vcs/git-annex:magicmime - Use libmagic to determine file MIME types
+dev-vcs/git-annex:network-uri - Get Network.URI from the network-uri package.
+dev-vcs/git-annex:pairing - Enable pairing of git annex repositories
+dev-vcs/git-annex:s3 - Enable Amazon S3 remote
+dev-vcs/git-annex:torrentparser - Use haskell torrent library to parse torrent files
+dev-vcs/git-annex:webapp - Enable git-annex webapp
+dev-vcs/git-annex:webdav - Enable webdav remote
+dev-vcs/gitg:glade - Install a glade catalog file
+dev-vcs/gitg:python - Install Python bindings for those plugins requiring it.
+dev-vcs/gitolite:contrib - Install user-contributed files
+dev-vcs/gitolite:tools - Install tools to e.g. convert a Gitosis config to gitolite or one to check if your setup is gitolite >= 3.x compatible
+dev-vcs/gitolite-gentoo:contrib - Install user-contributed files
+dev-vcs/gitolite-gentoo:tools - Install tools to e.g. convert a Gitosis config to gitolite or one to check if your setup is gitolite >= 3.x compatible
+dev-vcs/kdesvn:man - Build and install man pages
+dev-vcs/mercurial:bugzilla - Support bugzilla integration.
+dev-vcs/mercurial:gpg - Support signing with GnuPG.
+dev-vcs/mercurial:tk - Install dev-lang/tk for hgk script.
+dev-vcs/rabbitvcs:caja - Enable extension for mate-base/caja
+dev-vcs/rabbitvcs:cli - Eanble console based frontend
+dev-vcs/rabbitvcs:diff - Use for diff command dev-util/meld
+dev-vcs/rabbitvcs:gedit - Enable plugin for app-editors/gedit
+dev-vcs/rabbitvcs:nautilus - Enable extension for gnome-base/nautilus
+dev-vcs/rabbitvcs:thunar - Enable extension for xfce-base/thunar
+dev-vcs/subversion:ctypes-python - Build and install Ctypes Python bindings
+dev-vcs/subversion:dso - Enable runtime module search
+dev-vcs/subversion:extras - Install extra scripts (examples, tools, hooks)
+dev-vcs/subversion:http - Enable http support using net-libs/serf
+dev-vcs/subversion:kwallet - Enable encrypted storage of passwords with kde-frameworks/kwallet
+games-action/beathazardultra:bundled-libs - Use the upstream provided bundled libraries.
+games-action/chromium-bsu:mixer - Enables media-libs/sdl-mixer sound backend instead of media-libs/openal one.
+games-action/d1x-rebirth:demo - Use the demo data instead of the full game
+games-action/d1x-rebirth:l10n_de - Provides German translations for the game's briefings, robot descriptions, and outro of the original campaign
+games-action/d1x-rebirth:music - Support for ingame music
+games-action/d1x-rebirth:opl3-musicpack - Include alternate version of the game's music, recorded with the Yamaha YMF262 OPL3 soundchip
+games-action/d1x-rebirth:sc55-musicpack - Include alternate version of the game's music, recorded with the Roland Sound Canvas SC-55 MIDI module
+games-action/d2x-rebirth:demo - Install games-action/descent2-demodata as well
+games-action/d2x-rebirth:l10n_de - Provides German translations for the game's briefings, robot descriptions, and outro of the original campaign
+games-action/d2x-rebirth:music - Support for ingame music
+games-action/d2x-rebirth:opl3-musicpack - Include alternate version of the game's music, recorded with the Yamaha YMF262 OPL3 soundchip
+games-action/d2x-rebirth:sc55-musicpack - Include alternate version of the game's music, recorded with the Roland Sound Canvas SC-55 MIDI module
+games-action/dxx-rebirth:data - Install data files
+games-action/dxx-rebirth:descent1 - Install Descent 1 resources and executable
+games-action/dxx-rebirth:descent2 - Install Descent 2 resources and executable
+games-action/dxx-rebirth:l10n_de - Provides German translations for the game's briefings, robot descriptions, and outro of the original campaign
+games-action/dxx-rebirth:music - Enable music support
+games-action/dxx-rebirth:opl3-musicpack - Include alternate version of the game's music, recorded with the Yamaha YMF262 OPL3 soundchip
+games-action/dxx-rebirth:sc55-musicpack - Include alternate version of the game's music, recorded with the Roland Sound Canvas SC-55 MIDI module
+games-action/dxx-rebirth:textures - Include high resolution (640x480) backgrounds, briefing images and fonts (Descent 1)
+games-action/hotline-miami:bundled-libs - Use bundled libraries.
+games-action/hotline-miami:launcher - Install qt launcher
+games-action/minetest:leveldb - Enable LevelDB backend
+games-action/minetest:luajit - Use dev-lang/luajit instead of dev-lang/lua
+games-action/minetest:postgres - Optionally use PostgreSQL as map backend
+games-action/minetest:redis - Enable redis backend via dev-libs/hiredis
+games-action/minetest:server - Build minetest server
+games-action/minetest:spatial - Enable SpatialIndex AreaStore backend
+games-action/solar2:bundled-libs - Use the upstream provided bundled libraries.
+games-action/super-hexagon:bundled-libs - Use the upstream provided bundled libraries.
+games-action/supermariowar:server - Compile and install Super Mario War server files
+games-action/supertuxkart:fribidi - Support for right-to-left languages
+games-action/supertuxkart:recorder - Enable recording with media-libs/libopenglrecorder
+games-action/supertuxkart:wiimote - Support for wiimote input devices
+games-action/swordandsworcery:bundled-libs - Use the upstream provided bundled libraries.
+games-action/trine2:bundled-libs - Use bundled libraries.
+games-action/trine2:launcher - Install gtk+ launcher
+games-arcade/bomns:editor - enables building the level editor
+games-arcade/burgerspace:network - Enable client-server support
+games-arcade/commandergenius:tremor - Use media-libs/tremor as ogg decoder instead of media-libs/libvorbis
+games-arcade/jumpnbump:music - Enable playing of background music
+games-arcade/lbreakout2:themes - Install additional themes
+games-arcade/moleinvasion:music - Download and install the music files
+games-arcade/performous:midi - Enable MIDI I/O support
+games-arcade/performous:songs - Install a few demo songs
+games-arcade/performous:tools - Install tools
+games-arcade/performous:webcam - Enable Webcam support
+games-arcade/savagewheels:fmod - Enable the fmod music and sound effects library
+games-arcade/slimevolley:net - Enable network support
+games-arcade/tuxanci:physfs - Use dev-games/physfs instead of dev-libs/libzip to load compressed data
+games-arcade/tuxanci:sound - Enable sound
+games-board/cockatrice:client - Build with client
+games-board/cockatrice:oracle - Build with oracle
+games-board/cockatrice:server - Compile server support
+games-board/crafty:no-opts - Don't try to enable crazy CFLAG options
+games-board/freedoko:backgrounds - Install additional background images
+games-board/freedoko:gnomecards - Install the gnome-games card set
+games-board/freedoko:kdecards - Install the KDE card set
+games-board/freedoko:net - Enable network game support
+games-board/freedoko:openclipartcards - Install the openclipartcards card set
+games-board/freedoko:pysolcards - Install the PySol card set
+games-board/freedoko:xskatcards - Install the XSkat card set
+games-board/grhino:gtp - Install the GTP (Go/Game Text Protocol) frontend
+games-board/knights:speech - Enable text-to-speech support
+games-board/pasang-emas:extras - Install some extra themes
+games-board/pioneers:help - Enable gnome ingame help via scrollkeeper
+games-board/pysolfc:extra-cardsets - Install extra cardsets
+games-board/pysolfc:sound - Enable sound support using dev-python/pygame
+games-board/spider:athena - Enable athena widgets
+games-board/stockfish:armv7 - Build for armv7; enables PIE
+games-board/stockfish:general-32 - Generic unoptimized 32-bits build
+games-board/stockfish:general-64 - Generic unoptimized 64-bits build
+games-board/stockfish:optimize - Enable upstream -O3 optimizations (default enabled)
+games-board/tablebase-syzygy:6-pieces - Install tablebases for 6 pieces (huge!)
+games-board/xboard:default-font - Install the default font that xboard uses
+games-board/xboard:zippy - Enable experimental zippy client
+games-emulation/dolphin:egl - Enable EGL support
+games-emulation/dolphin:evdev - Enable evdev input support
+games-emulation/dolphin:llvm - Enable the LLVM-based disassembler for debugger mode
+games-emulation/dolphin:log - Increase logging output
+games-emulation/dolphin:lto - Add support for link-time optimizations.
+games-emulation/dosbox:glide - Enable unofficial Glide emulation via media-libs/openglide
+games-emulation/fceux:logo - Enable the ability to add a logo screen when creating AVIs
+games-emulation/generator:sdlaudio - Enable SDL Audio
+games-emulation/higan:icarus - Build icarus library manager
+games-emulation/higan:udev - Enable udev based input
+games-emulation/m64py:7z - Ensure support for .7z archives.
+games-emulation/m64py:rar - Ensure support for .rar archives.
+games-emulation/mednafen:debugger - Build with internal debugger
+games-emulation/mednafen:pax_kernel - Triggers a paxmarking of the binary
+games-emulation/mupen64plus:audio-sdl - Enable SDL audio plugin.
+games-emulation/mupen64plus:input-sdl - Enable SDL input plugin.
+games-emulation/mupen64plus:rsp-hle - Enable HLE RSP plugin.
+games-emulation/mupen64plus:ui-console - Enable default console UI.
+games-emulation/mupen64plus:ui-m64py - Enable PyQt5 UI using games-emulation/m64py.
+games-emulation/mupen64plus:video-glide64mk2 - Enable Glide64mk2 video plugin.
+games-emulation/mupen64plus:video-rice - Enable Rice video plugin.
+games-emulation/mupen64plus-core:debugger - Build the debugger
+games-emulation/mupen64plus-core:gles2 - Use GLES2 instead of OpenGL
+games-emulation/mupen64plus-core:new-dynarec - Enable new experimental dynamic recompiler implementation (only for x86 and arm)
+games-emulation/mupen64plus-core:osd - Overlay emulator messages using on-screen-display
+games-emulation/mupen64plus-video-glide64mk2:gles2 - Use GLES2 instead of OpenGL
+games-emulation/mupen64plus-video-glide64mk2:hires - Support hi-resolution textures (requires dev-libs/boost)
+games-emulation/mupen64plus-video-rice:gles2 - Use GLES2 instead of OpenGL
+games-emulation/nestopia:gui - Enable GUI
+games-emulation/pcsxr:cdio - Use libcdio for CD support
+games-emulation/pcsxr:sdl - Use SDL sound backend (other parts of SDL are used unconditionally)
+games-emulation/ppsspp:headless - Build headless version of the PPSSPP
+games-emulation/ppsspp:system-ffmpeg - Use the system-wide media-video/ffmpeg instead of bundled
+games-emulation/sdlmame:arcade - Enable the Multiple Arcade Machine Emulator for arcade games support
+games-emulation/sdlmame:mess - Enable the Multi Emulator Super System for game system support
+games-emulation/sdlmame:tools - Build development tools shared between sdlmame and sdlmess
+games-emulation/snes9x:netplay - Enable playing ROMs over the network (not recommended)
+games-emulation/snes9x:xrandr - Enable support for the X xrandr extension
+games-emulation/vbam:link - Enable GBA linking functionality
+games-emulation/yabause:pic - disable optimized assembly code that is not PIC friendly
+games-emulation/zsnes:debug - Enable the builtin debugger
+games-emulation/zsnes:pax_kernel - Triggers a paxmarking of the binary
+games-engines/frobtads:tads2compiler - Build TADS2 compiler
+games-engines/frobtads:tads3compiler - Build TADS3 compiler
+games-engines/odamex:master - Build master server target (advertises odamex server list)
+games-engines/odamex:odalaunch - Build the wxwidgets based launcher.
+games-engines/odamex:portmidi - Enable portmidi support.
+games-engines/odamex:server - Build server target.
+games-engines/openmw:devtools - Install development tools like bsatool, esmtool and opencs.
+games-engines/renpy:development - Install IDE for game developers and an empty game template
+games-engines/scummvm:fluidsynth - compile with support for fluidsynth
+games-engines/scummvm:mpeg2 - enable mpeg2 codec for cutscenes
+games-engines/scummvm:unsupported - enable unsupported and/or broken game engines (you're on your own)
+games-engines/solarus:doc - Install doxygen developer documentation.
+games-engines/solarus:luajit - Use LuaJIT instead of default Lua.
+games-engines/stratagus:fluidsynth - compile with support for fluidsynth
+games-fps/alienarena:vidmode - Link against x11-libs/libXxf86vm. Required for full-screen support.
+games-fps/darkplaces:cdsound - Enables using CD audio in the engine
+games-fps/darkplaces:demo - Uses the demo data from quake1 (quake1-demodata)
+games-fps/darkplaces:lights - Install and setup the updated light maps
+games-fps/darkplaces:textures - Install and setup the updated textures
+games-fps/doom-data:doomsday - Add wrapper to run it within doomsday
+games-fps/doom3:dedicated - install only as a dedicated game server
+games-fps/doom3:roe - Adds support for the Resurrection of Evil expansion
+games-fps/doomsday:demo - Install launcher dor doom1.wad from games-fps/doom-data
+games-fps/doomsday:doom - Install launcher for jdoom game
+games-fps/doomsday:fluidsynth - Build the FluidSynth sound driver
+games-fps/doomsday:freedoom - Install launcher for doom1.wad from games-fps/freedoom
+games-fps/doomsday:heretic - Install launcher for jheretic game
+games-fps/doomsday:hexen - Install launcher for jhexen game
+games-fps/doomsday:resources - Enable support for games-fps/doomsday-resources in jdoom launcher
+games-fps/doomsday:snowberry - Install Snowberry doomsday front-end
+games-fps/doomsday:tools - Build additional tools such as doomsday-shell, md2tool and texc
+games-fps/duke3d:demo - Install the demo files
+games-fps/duke3d:pic - disable optimized assembly code that is not PIC friendly
+games-fps/duke3d-data:gog - Extract the data from the GOG.com installer.
+games-fps/eduke32:demo - Install games-fps/duke3d-demodata as well
+games-fps/eduke32:gtk - Compile with gtk launcher
+games-fps/eduke32:offensive - Include optional XXX texture pack (needs USE 'textures')
+games-fps/eduke32:opl-musicpack - Include optional OPL (AdLib) music pack
+games-fps/eduke32:samples - Install samples
+games-fps/eduke32:sc55-musicpack - Include optional Roland SC-55 music pack
+games-fps/eduke32:server - Compile with server support
+games-fps/eduke32:textures - Include optional high-resolution textures (needs USE 'opengl')
+games-fps/eduke32:tools - Build several tools for modding and development
+games-fps/eduke32:vpx - Enable support for WebM VP8 Codecs (needs USE 'opengl')
+games-fps/lsdldoom:freedoom - Install games-fps/freedoom wad file
+games-fps/lsdldoom:net - Enables network game support
+games-fps/lsdldoom:shareware - Install games-fps/doom-data for shareware wad file
+games-fps/nexuiz:maps - Install the community map pack
+games-fps/quake2-icculus:demo - Install the demo files (quake2-demodata) and configure for use
+games-fps/quake2-icculus:qmax - Build the pretty version (quake max)
+games-fps/quake2-icculus:rogue - Build support for the 'Ground Zero' Mission Pack (rogue)
+games-fps/quake2-icculus:xatrix - Build support for the 'The Reckoning' Mission Pack (xatrix)
+games-fps/quake3:mumble - Adds player-location (positional audio) support to VoIP
+games-fps/quake3:teamarena - Adds support for Team Arena expansion pack
+games-fps/quake3:voice - Adds VoIP support
+games-fps/quake3-bin:teamarena - Adds support for Team Arena expansion pack
+games-fps/quake3-demo:dedicated - install only as a dedicated game serer
+games-fps/quakeforge:wildmidi - enable libWildMidi support
+games-fps/quakeforge:xdg - enable XDG support
+games-fps/qudos:demo - Install the demo files (quake2-demodata) and configure for use
+games-fps/qudos:mods - Build support for the quake2 mission packs
+games-fps/qudos:qmax - Build the pretty version (quake max)
+games-fps/qudos:textures - Install the enhanced textures (quake2-textures)
+games-fps/redeclipse:dedicated - Install only as a dedicated game server
+games-fps/rott:demo - Install the shareware version
+games-fps/sauerbraten:server - Compile server support
+games-fps/turtlearena:mumble - Adds player-location (positional audio) support to VoIP
+games-fps/turtlearena:server - Build server target
+games-fps/turtlearena:voice - Adds VoIP support
+games-fps/unreal-tournament-goty:S3TC - Add the extra fancy textures to UT ... only works on certain cards (nvidia/ati/s3)
+games-fps/urbanterror:altgamma - Alternative way for gamma setting with modesetting driver
+games-fps/urbanterror:client - Build binary for client (includes code for non-dedicated server)
+games-fps/urbanterror:mumble - Use Mumble for ingame VoIP (experimental)
+games-fps/urbanterror:opus - Use opus as sound codec
+games-fps/urbanterror:server - Build binary for dedicated server
+games-fps/urbanterror:skeetshootmod - Build support for skeetshoot mod for specific maps
+games-fps/urbanterror:voip - Use ioq3 ingame VoIP (experimental)
+games-fps/worldofpadman:maps - Install extra maps (PadPack)
+games-fps/xonotic:ode - Enable support for physics engine from dev-games/ode
+games-fps/yamagi-quake2:client - Build client
+games-fps/yamagi-quake2:ctf - Build support for the 'Capture The Flag' addon
+games-fps/yamagi-quake2:rogue - Build support for the 'Ground Zero' Mission Pack
+games-fps/yamagi-quake2:xatrix - Build support for the 'The Reckoning' Mission Pack
+games-kids/crayon-physics:bundled-libs - Use the upstream provided bundled libraries.
+games-misc/katawa-shoujo:system-renpy - Use games-engines/renpy instead of the bundled one (experimental)
+games-misc/little-inferno:bundled-libs - Use bundled libraries.
+games-misc/ponysay:fish-completion - Enable fish completion support
+games-misc/ponysay:non-free - Install non-free ponies (i.e. from the MLP franchise)
+games-misc/xcowsay:fortune - Installs the fortune-mod xcow binary
+games-mud/tf:atcp - enable ATCP support.
+games-mud/tf:gmcp - enable GMCP support.
+games-mud/tf:option102 - enable telnet option 102 support.
+games-puzzle/cuyo:music - Enable playing of background music
+games-puzzle/nightsky:bundled-libs - Use the upstream provided bundled libraries.
+games-puzzle/numptyphysics:user-levels - Install some fun user-created levels
+games-puzzle/pingus:music - Enable playing of background music
+games-puzzle/sgt-puzzles:gtk3 - Use x11-libs/gtk+:3 instead of x11-libs/gtk+:2
+games-puzzle/tiny-and-big:bundled-libs - Use the upstream provided bundled libraries.
+games-puzzle/xlogical:alt_gfx - Use alternate graphics which are closer to the original Amiga version
+games-roguelike/FTL:bundled-libs - Use bundled libraries.
+games-roguelike/angband:sound - Enable and install sounds
+games-roguelike/nethack:experimental - Enable experimental features (showscore and status_hilite)
+games-roguelike/stone-soup:luajit - Use dev-lang/luajit as scripting backend instead of dev-lang/lua.
+games-roguelike/stone-soup:ncurses - Enable for console (uses ncurses) based build. (can be enabled on top of tiles)
+games-roguelike/stone-soup:tiles - Enable for graphical (tiled) build. (can be enabled on top of ncurses)
+games-roguelike/tomenet:server - Compile server support
+games-rpg/arx-fatalis-data:gog - Extract the data from the GOG.com installer.
+games-rpg/arx-libertatis:c++0x - Build ROOT using the C++11 standard.
+games-rpg/arx-libertatis:crash-reporter - Build a dev-qt/qtgui-based tool that allows to submit crash information to the upstream backtracker.
+games-rpg/arx-libertatis:debug - Enable asserts and debug logging.
+games-rpg/arx-libertatis:static - Link libraries statically, currently only media-libs/glew
+games-rpg/arx-libertatis:tools - Build tools that can extract the game's data and save files.
+games-rpg/arx-libertatis:unity-build - Build everything in one big source file, allowing for faster build times and better optimizations at the cost of higher memory usage.
+games-rpg/daimonin-client:music - Install extra music
+games-rpg/drascula:sound - Install optional audio files
+games-rpg/dreamweb:doc - High-resolution scans of the written material in the original UK game box
+games-rpg/dungeon-defenders:bundled-libs - Use the upstream provided bundled libraries.
+games-rpg/eternal-lands-data:bloodsuckermaps - Will install Bloodsucker's Maps in place of the official map files
+games-rpg/eternal-lands-data:music - Enables in-game music
+games-rpg/eternal-lands-data:sound - Enables in-game sound effects
+games-rpg/grimrock:bundled-libs - Use bundled libraries.
+games-rpg/kqlives:cheats - Enable cheating mode
+games-rpg/manaplus:mumble - Enable support for voice chat
+games-rpg/manaplus:pugixml - Use dev-libs/pugixml for XML parsing isntead of dev-libs/libxml2
+games-rpg/manaplus:sdl2 - Use libsdl2 instead of libsdl
+games-rpg/sumwars:tools - Builds editor tools
+games-rpg/to-the-moon:bundled-libs - Use bundled libraries
+games-simulation/flightgear:dbus - Enable screensaver DBus interaction
+games-simulation/flightgear:gdal - Enable alternative terrain engine based on pagedLOD using sci-libs/gdal
+games-simulation/flightgear:qt5 - Build Qt5 launcher application
+games-simulation/flightgear:udev - Enable event-based Input devices through virtual/udev
+games-simulation/flightgear:utils - Build various utilities (fgpanel, fgviewer among others)
+games-simulation/openrct2:multiplayer - Enable multiplayer functionality
+games-simulation/openrct2:twitch - Enable Twitch support
+games-simulation/openttd:aplaymidi - Enables midi music in game, using aplaymidi as an external player
+games-simulation/openttd:dedicated - Build only the openttd server, and not the client.
+games-simulation/openttd:lzo - Enables LZO compression for savegames. This is only needed to load extremely old savegames. (versions before 0.2)
+games-simulation/openttd:openmedia - Enables the free open media sets: OpenGFX, OpenSFX, OpenMSX, removing the requirement for proprietary TTD assets to play OpenTTD.
+games-simulation/singularity:music - Install music files
+games-sports/speed-dreams:xrandr - Enable support for the X xrandr extension
+games-sports/xmoto:editor - Depend on inkscape, scripts to convert svg to level (svg2lvl)
+games-strategy/0ad:editor - Include Atlas scenario editor projects
+games-strategy/0ad:lobby - Enable the use of net-libs/gloox and the multiplayer lobby
+games-strategy/0ad:nvtt - Support for some uncompressed data formats via media-gfx/nvidia-texture-tools (might be needed for some mods)
+games-strategy/colobot:devbuild - TODO
+games-strategy/colobot:tools - Build tools
+games-strategy/colobot-data:music - Enable music support
+games-strategy/colobot-data:music_flac_convert - Fetch flac music and convert it to ogg
+games-strategy/colobot-data:music_ogg - Fetch ogg music
+games-strategy/defcon-demo:system-libs - Use system libraries instead of the ones included in the upstream distribution.
+games-strategy/freeciv:aimodules - Support for dynamically loadable AI modules (server-side)
+games-strategy/freeciv:auth - Add authentication capability via mysql, postgres or sqlite3
+games-strategy/freeciv:mapimg - Additional mag image toolkit via media-gfx/imagemagick
+games-strategy/freeciv:modpack - Build the freeciv-modpack-program to download/install mods
+games-strategy/freeciv:server - Enable server support. Disabling this will also make it impossible to start local games.
+games-strategy/freeciv:sound - Add support for sound provided by media-libs/sdl-mixer
+games-strategy/freeciv:system-lua - Use dev-lang/lua instead of the bundled liblua
+games-strategy/freesynd:devtools - Build development tools
+games-strategy/heroes3:maps - Installs optional map data
+games-strategy/heroes3:music - Installs optional music data
+games-strategy/heroes3:sounds - Installs optional sound data
+games-strategy/ja2-stracciatella:editor - Adds necessary file to run the editor
+games-strategy/ja2-stracciatella:ru-gold - Support for russian gold ja2 version
+games-strategy/liquidwar6:doc - Convert the info pages to html
+games-strategy/liquidwar6:gles2 - Enable OpenGL ES 2.0 support
+games-strategy/liquidwar6:gtk - Used to display error/critical messages
+games-strategy/liquidwar6:maps - Install extra maps
+games-strategy/liquidwar6:ogg - Enable mod-ogg via media-libs/sdl-mixer (currently the only sound provider)
+games-strategy/liquidwar6:readline - Enable interactive script shell for hacking
+games-strategy/megaglest:editor - Build map editor
+games-strategy/megaglest:fribidi - Enable FriBIDi support
+games-strategy/megaglest:model-viewer - Build model viewer
+games-strategy/megaglest:streflop - Use the library streflop. Out of synchs may occur if not enabled.
+games-strategy/megaglest:tools - Build model import/export tools
+games-strategy/megaglest:unicode - Use unicode strings for wxwidgets
+games-strategy/megaglest:wxuniversal - Use the wxUniversal port which implements the various GUI controls by drawing them itself
+games-strategy/naev:mixer - Enables media-libs/sdl-mixer sound backend in addition to media-libs/openal one.
+games-strategy/seven-kingdoms:network - Enable support for multiplayer via media-libs/sdl-net
+games-strategy/ufo-ai:editor - Build map editor
+games-strategy/uqm:music - download and install music files (large)
+games-strategy/uqm:remix - download and install music remix files (large)
+games-strategy/uqm:voice - download and install voice files (large)
+games-strategy/wesnoth:fribidi - Support for right-to-left languages
+games-strategy/wesnoth:server - Enable compilation of server
+games-util/gslist:web - Enable the web interface
+games-util/pyfa:graph - Enable support for graphs
+games-util/wit:fuse - Enable image mount support via fuse
+gnome-base/gconf:ldap - Build backend which enables default mail accounts, addressbooks and calendars for Evolution to be configured using each user's LDAP entry."
+gnome-base/gdm:fprint - Enables experimental fingerprint authentication using sys-auth/fprintd
+gnome-base/gdm:plymouth - Enable support for smooth transition from sys-boot/plymouth
+gnome-base/gnome:classic - Install gnome-extra/gnome-shell-extensions for the Gnome Shell Classic mode
+gnome-base/gnome:extras - Install additional GNOME applications
+gnome-base/gnome-common:autoconf-archive - Pull in sys-devel/autoconf-archive for ax_*.m4 files instead of installing them from the gnome-common tarball
+gnome-base/gnome-control-center:colord - Support color management using x11-misc/colord
+gnome-base/gnome-control-center:gnome-online-accounts - Enable configuration panel for net-libs/gnome-online-accounts accounts
+gnome-base/gnome-control-center:ibus - Enable support for enhanced input methods through app-i18n/ibus
+gnome-base/gnome-desktop:license-docs - Install help files documenting GNOME's licenses
+gnome-base/gnome-extra-apps:games - Install Gnome Games
+gnome-base/gnome-extra-apps:share - Install the gnome-extra/gnome-user-share personal file sharing tool
+gnome-base/gnome-extra-apps:shotwell - Install the media-gfx/shotwell photo manager
+gnome-base/gnome-extra-apps:tracker - Install the app-misc/tracker indexer and the GNOME packages that require it
+gnome-base/gnome-keyring:ssh-agent - Use GNOME Keyring to unlock SSH keys. Recommended unless you are using ECDSA or Ed25519 keys.
+gnome-base/gnome-light:gnome-shell - Install gnome-base/gnome-shell and x11-wm/mutter for the standard GNOME 3 desktop mode
+gnome-base/gnome-settings-daemon:colord - Support color management using x11-misc/colord
+gnome-base/gnome-settings-daemon:openrc-force - Skip systemd dependency (#480336), enabling this flag will become your setup to be fully unsupported by upstream and downstream Gnome team. Do not try to enable it unless completely needed
+gnome-base/gnome-shell:browser-extension - Ensure the presence of extensions.gnome.org native connector gnome-extra/chrome-gnome-shell
+gnome-base/gnome-shell:ibus - Enable support for enhanced input methods through app-i18n/ibus
+gnome-base/gnome-shell:openrc-force - Skip systemd dependency (#480336), enabling this flag will become your setup to be fully unsupported by upstream and downstream Gnome team. Do not try to enable it unless completely needed
+gnome-base/gvfs:afp - Enables support for accessing AFP (Apple Filing Protocol) network shares
+gnome-base/gvfs:archive - Enables support for accessing files in archives transparently via app-arch/libarchive
+gnome-base/gvfs:bluray - Enable playback of Blu-ray filesystems using media-libs/libbluray
+gnome-base/gvfs:elogind - Use sys-auth/elogind for session tracking.
+gnome-base/gvfs:fuse - Enables fuse mount points in $HOME/.gvfs for legacy application access
+gnome-base/gvfs:gnome-online-accounts - Enable configuration panel for net-libs/gnome-online-accounts accounts
+gnome-base/gvfs:google - Enables support for accessing Google accounts via dev-libs/libgdata
+gnome-base/gvfs:http - Enable the HTTP/DAV backend using net-libs/libsoup
+gnome-base/gvfs:nfs - Enable NFS client support via net-fs/libnfs.
+gnome-base/gvfs:udev - Enable udev base replacement code for cdda feature
+gnome-base/libglade:tools - Install libglade-convert Python script.
+gnome-base/libgnomecanvas:glade - Enable glade support
+gnome-base/librsvg:tools - Build svg viewer tool
+gnome-base/nautilus:packagekit - Use packagekit to search for programs to open unknown file types
+gnome-base/nautilus:previewer - Use gnome-extra/sushi to preview files from the file mananger
+gnome-base/nautilus:sendto - Enable the nautilus-sendto extension to send files to various locations/devices
+gnome-base/nautilus:tracker - Add support for app-misc/tracker search
+gnome-base/orbit:pic - Force libname-server-2 to be built as PIC; needed on hardened systems
+gnome-extra/cinnamon-control-center:colord - Support color management using x11-misc/colord
+gnome-extra/cinnamon-settings-daemon:colord - Support color management using x11-misc/colord
+gnome-extra/evolution-data-server:api-doc-extras - Build documentation for private APIs
+gnome-extra/evolution-data-server:berkdb - sys-libs/db support needed to migrate old (pre-3.12 evolution versions) addressbook data
+gnome-extra/evolution-data-server:gnome-online-accounts - Enable net-libs/gnome-online-accounts based Google authentication support
+gnome-extra/evolution-data-server:google - Enable internal Google authentication support. If gnome-online-accounts is enabled and used, this is not necessary, but both can be supported at the same time with different setup at runtime
+gnome-extra/evolution-data-server:weather - Enable optional weather calendar support
+gnome-extra/gnome-builder:clang - Provide integration with sys-devel/clang for best possible C/C++ autocompletion, semantic highlighting, symbol resolving, and diagnostics support
+gnome-extra/gnome-builder:git - Provide support for the Git version control system via dev-libs/libgit2-glib (such as setup of Git for New Project, direct cloning for Open Project and changed lines indicators in the editor gutter)
+gnome-extra/gnome-builder:sysprof - Provide an integrated profiler via dev-util/sysprof
+gnome-extra/gnome-builder:vala - Provide an autoindenter, autocompletion, diagnostics, and symbol resolver for Vala
+gnome-extra/gnome-builder:webkit - Enable net-libs/webkit-gtk using plugins support and the HTML/Markdown previewer plugin
+gnome-extra/gnome-color-manager:packagekit - Enable support for the distro-neutral package manager GUI app-admin/packagekit
+gnome-extra/gnome-commander:chm - Enable metadata support for Microsoft Compiled HTML Help files
+gnome-extra/gnome-commander:gsf - Add metadata support for OLE, OLE2 and ODF
+gnome-extra/gnome-commander:pdf - Add metadata support for PDF
+gnome-extra/gnome-commander:python - Add support for python plugins
+gnome-extra/gnome-commander:samba - Add support for SAMBA (Windows File and Printer sharing)
+gnome-extra/gnome-commander:taglib - Add metadata support for ID3, Vorbis, FLAC and APE
+gnome-extra/gnome-commander:unique - Enable single instance support using dev-libs/libunique
+gnome-extra/gnome-dvb-daemon:totem - Build a plugin for media-video/totem
+gnome-extra/gnome-system-monitor:systemd - Display sys-apps/systemd metadata, e.g. unit names, for running processes
+gnome-extra/libgda:canvas - Enable support for x11-libs/goocanvas
+gnome-extra/libgda:http - Enable embedded net-libs/libsoup based server
+gnome-extra/libgda:json - Enable support for JSON format
+gnome-extra/libgda:mdb - Enable support for Microsoft Access database using app-office/mdbtools
+gnome-extra/libgda:reports - Install tools for generating graphical reports
+gnome-extra/libgda:sourceview - Enable support for x11-libs/gtksourceview
+gnome-extra/libgsf:gtk - Enable use of gdk in thumbnailer
+gnome-extra/nemo:packagekit - Use packagekit to search for programs to open unknown file types
+gnome-extra/nemo:tracker - Add support for app-misc/tracker search
+gnome-extra/nm-applet:gcr - Enable advanced certificate chooser, requires app-crypt/gcr
+gnome-extra/nm-applet:modemmanager - Enable support for mobile broadband devices using net-misc/modemmanager
+gnome-extra/nm-applet:teamd - Enable teamd configuration editor
+gnome-extra/sushi:office - Support viewing file formats such as generated by app-office/libreoffice
+gnome-extra/synapse:plugins - Build support for plugins using librest
+gnome-extra/synapse:zeitgeist - Add support for Zeitgeist event tracking system
+gnustep-apps/gemas:projectcenter - Build and install plugin for gnustep-apps/projectcenter
+gnustep-apps/gworkspace:gwmetadata - Enable the metadata indexing and searching system
+gnustep-base/gnustep-back-art:xim - Enable X11 XiM input method
+gnustep-base/gnustep-back-cairo:xim - Enable X11 XiM input method
+gnustep-base/gnustep-back-xlib:xim - Enable X11 XiM input method
+gnustep-base/gnustep-gui:speech - Audio support using app-accessibility/flite
+gnustep-base/gnustep-make:libobjc2 - Enables use of the GNUstep Objective-C runtime (gnustep-base/libobjc2) with non-fragile ABI and sys-devel/clang compiler
+gnustep-base/gnustep-make:native-exceptions - Enables use of the native Objective-C exception support (@try/@catch/@finally) built-in objective-c exceptions with compilers that support it
+gnustep-base/libobjc2:boehm-gc - Enable Hans Boehm's garbage collector (dev-libs/boehm-gc). Not recommended by upstream
+kde-apps/akonadi:designer - Install plugin for dev-qt/designer
+kde-apps/akonadi:tools - Install tools for developers and testing
+kde-apps/analitza:eigen - Enable dev-cpp/eigen mathematical templates support
+kde-apps/ark:zip - Enable ZIP archive support via dev-libs/libzip
+kde-apps/artikulate:qtmedia - Enable playback via Qt5Multimedia
+kde-apps/cantor:R - Enable dev-lang/R backend support
+kde-apps/cantor:analitza - Enable kde-apps/analitza backend support
+kde-apps/cantor:julia - Enable dev-lang/julia backend support
+kde-apps/cantor:qalculate - Enable sci-libs/libqalculate backend support
+kde-apps/dolphin:thumbnail - Enables video thumbnail generation
+kde-apps/dolphin-plugins:bazaar - Enable support for the bazaar VCS
+kde-apps/dolphin-plugins:dropbox - Enable support for the dropbox fileviewer plugin
+kde-apps/dolphin-plugins:git - Enable support for the git VCS
+kde-apps/dolphin-plugins:mercurial - Enable support for the mercurial VCS
+kde-apps/gwenview:fits - Enable support for NASA's sci-libs/cfitsio library
+kde-apps/gwenview:kipi - Support for the KDE Image Plugin Interface
+kde-apps/k3b:emovix - Enable burning support for eMoviX images
+kde-apps/kalzium:editor - Enable the embedded molecule editor/viewer
+kde-apps/kalzium:solver - Enable the equation solver
+kde-apps/kanagram:speech - Enable text-to-speech support
+kde-apps/kate:addons - Build and install additional plugins
+kde-apps/kde-apps-meta:pim - Pull in KDE PIM suite
+kde-apps/kde-apps-meta:sdk - Pull in developer-specific meta-packages
+kde-apps/kdeadmin-meta:cron - Installs KDE application for virtual/cron configuration
+kde-apps/kdegraphics-mobipocket:thumbnail - Enables thumbnail generation
+kde-apps/kdemultimedia-meta:cdrom - Include packages for optical discs
+kde-apps/kdenlive:freesound - Enable freesound.org credentials support via dev-qt/qtwebkit to download files
+kde-apps/kdenlive:gles2 - Use GLES 2.0 or later instead of full OpenGL
+kde-apps/kdenlive:jogshuttle - Enable support for Jog-Shuttle devices
+kde-apps/kdepim-addons:importwizard - Enable additional import plugins for kde-apps/akonadi-import-wizard
+kde-apps/kdepim-runtime:speech - Enable text-to-speech support
+kde-apps/kdeutils-meta:floppy - Install kde-apps/kfloppy to format and create DOS or ext2fs filesystems in a floppy.
+kde-apps/keditbookmarks:man - Build and install man pages
+kde-apps/kget:bittorrent - Enable bittorrent transfer plugin through net-libs/libktorrent
+kde-apps/kget:gpg - Enable signature verification by GpgME++ via app-crypt/gpgme
+kde-apps/kget:mms - Enable MMS (Microsoft Media Server) plugin through media-libs/libmms
+kde-apps/kig:geogebra - Support files created by sci-mathematics/geogebra
+kde-apps/kig:scripting - Support Python scripting
+kde-apps/kio-extras:activities - Enable activities kioslave and fileitem plugin
+kde-apps/kio-extras:htmlthumbs - Enable HTML thumbnail previews via dev-qt/qtwebengine
+kde-apps/kio-extras:man - Enable manpages kioslave
+kde-apps/kio-extras:phonon - Enable file audio preview plugin using media-libs/phonon
+kde-apps/kio-extras:sftp - Enable SFTP protocol support using net-libs/libssh
+kde-apps/kmag:keyboardfocus - Enable keyboard focus tracking
+kde-apps/konqueror:activities - Enable kactivities support
+kde-apps/konqueror:speech - Build text-to-speech plugin
+kde-apps/kopete:addbookmarks - Automatically add incoming urls to bookmarks.
+kde-apps/kopete:autoreplace - Automatically replace selected text
+kde-apps/kopete:contactnotes - Enables writing personal notes for contacts.
+kde-apps/kopete:gadu - Enable the Gadu protocol handler.
+kde-apps/kopete:groupwise - Enable the Groupwise protocol handler.
+kde-apps/kopete:highlight - Allows you to specify highlights on specific events.
+kde-apps/kopete:history - Enables saving chat history.
+kde-apps/kopete:latex - Embed latex formatted text into messages.
+kde-apps/kopete:meanwhile - Enable the Sametime protocol handler.
+kde-apps/kopete:nowlistening - Shows song you currently listen to in your status/etc. Bindings for many players.
+kde-apps/kopete:otr - Allows crypting your chat (drugs and talking nonsense are considered as good alternatives ;]).
+kde-apps/kopete:pipes - Send messages to external pipe.
+kde-apps/kopete:privacy - Filter for incoming messages
+kde-apps/kopete:statistics - Everybody loves statistic graphs, especially cake ones. ;]
+kde-apps/kopete:testbed - Enable the testbed protocol.
+kde-apps/kopete:texteffect - Various fancy text effects for your messages (don't ever consider writing us with this enabled ;]).
+kde-apps/kopete:translator - Translate incoming and outgoing messages.
+kde-apps/kopete:urlpicpreview - Enables in conversation pictures preview.
+kde-apps/kopete:webpresence - Show your status and some more information on web.
+kde-apps/kopete:winpopup - Enable pop-up messages sending on windows. (same as good old "net send" messages ;])
+kde-apps/kopete:yahoo - Enable yahoo protocol support.
+kde-apps/kopete:zeroconf - Enable Link-Local Messaging via the bonjour protocol.
+kde-apps/kpimtextedit:designer - Build plugins for dev-qt/designer
+kde-apps/kpimtextedit:speech - Enable text-to-speech support
+kde-apps/kstars:fits - Enable support for NASA's sci-libs/cfitsio library
+kde-apps/kstars:indi - Enable support for Astronomical control library using libindi
+kde-apps/kstars:wcs - Enable support for World Coordinate System library using wcslib
+kde-apps/kstars:xplanet - Enable support for Xplanet
+kde-apps/ktp-accounts-kcm:experimental - Enables disabled telepathy services (currently only steam)
+kde-apps/ktp-common-internals:otr - Enable support for encrypted conversations using Off-The-Records messaging
+kde-apps/ktp-common-internals:sso - Enable support for Single sign-on through KAccounts
+kde-apps/ktp-text-ui:speech - Enable incoming messages to be read out using text-to-speech
+kde-apps/kwave:opus - Enable Opus audio codec support
+kde-apps/kwave:qtmedia - Enable playback via Qt5Multimedia
+kde-apps/libkdepim:designer - Build plugins for dev-qt/designer
+kde-apps/mailcommon:designer - Build plugins for dev-qt/designer
+kde-apps/marble:aprs - Enable support for APRS data sources
+kde-apps/marble:designer - Install plugin for dev-qt/designer
+kde-apps/marble:phonon - Enable sound support via media-libs/phonon
+kde-apps/marble:shapefile - Enable support for ESRI shapefiles
+kde-apps/okteta:designer - Build plugins for dev-qt/designer
+kde-apps/okular:chm - Enable support for Microsoft Compiled HTML Help files
+kde-apps/okular:epub - Enable E-Book support via app-text/ebook-tools
+kde-apps/okular:image-backend - Enable image viewing support
+kde-apps/okular:markdown - Enable Markdown support via app-text/discount
+kde-apps/okular:mobi - Enable mobipocket support
+kde-apps/okular:mobile - Enable Plasma mobile support
+kde-apps/okular:plucker - Enable Plucker E-Book for Palm OS devices support
+kde-apps/okular:share - Enable support for a share menu using kde-frameworks/purpose
+kde-apps/okular:speech - Enable text-to-speech support
+kde-apps/pimcommon:designer - Build plugins for dev-qt/designer
+kde-apps/spectacle:kipi - Enable support for the KDE Image Plugin Interface
+kde-apps/spectacle:share - Enable support for a share menu using kde-frameworks/purpose
+kde-apps/step:qalculate - Enable the libqalculate library for unit conversion
+kde-frameworks/frameworkintegration:appstream - Enable AppStream software metadata support
+kde-frameworks/kconfigwidgets:man - Build and install man pages
+kde-frameworks/kded:man - Build and install man pages
+kde-frameworks/kdelibs:qt3support - Enable kde3support/qt3support for very old applications
+kde-frameworks/kdesignerplugin:designer - Build KF5 widgets plugin for QtDesigner
+kde-frameworks/kdesignerplugin:webkit - Build kdewebkit plugin for QtDesigner
+kde-frameworks/kfilemetadata:epub - Enable support for reading EPUB ebook metadata
+kde-frameworks/kfilemetadata:office - Enable support for reading ODF and OOXML metadata
+kde-frameworks/kimageformats:eps - Support the EPS graphics file format
+kde-frameworks/kinit:caps - Capabilities support for improved security and better OOM handling
+kde-frameworks/kinit:man - Build and install man pages
+kde-frameworks/kio:kwallet - Enable permanent storage of passwords for kpasswdserver with kde-frameworks/kwallet
+kde-frameworks/knotifications:speech - Enable text-to-speech notification support
+kde-frameworks/knotifyconfig:phonon - Add sound support via media-libs/phonon
+kde-frameworks/kpackage:man - Build and install man pages
+kde-frameworks/kservice:man - Build and install man pages
+kde-frameworks/ktexteditor:editorconfig - Enable support for EditorConfig configuration files
+kde-frameworks/ktextwidgets:speech - Enable text-to-speech support
+kde-frameworks/kwallet:gpg - Support wallets with GnuPG encryption in addition to the default blowfish-encrypted file
+kde-frameworks/kwallet:man - Build and install man pages
+kde-frameworks/kxmlgui:attica - Enable support for kde-frameworks/attica
+kde-frameworks/networkmanager-qt:teamd - Enable Teamd control support
+kde-frameworks/plasma:gles2 - Use GLES 2.0 or later instead of full OpenGL
+kde-frameworks/purpose:kaccounts - Enable support for system-wide defined KAccounts
+kde-frameworks/sonnet:aspell - Enable the app-text/aspell spell-checking backend
+kde-frameworks/sonnet:hunspell - Enable the app-text/hunspell spell-checking backend
+kde-misc/kdeconnect:app - Enable experimental kcapp frontend
+kde-misc/kdeconnect:wayland - Enable kwin_wayland support for mousepad plugin using kde-frameworks/kwayland
+kde-misc/kimtoy:scim - Enable Smart Common Input Method support
+kde-misc/kio-gdrive:kaccounts - Use kde-apps/kaccounts-integration backend (default) instead of dev-libs/qtkeychain
+kde-misc/kmarkdownwebview:webkit - Use dev-qt/qtwebkit instead of dev-qt/qtwebengine
+kde-misc/tellico:discid - Add support for reading disc IDs from audio CDs
+kde-plasma/kde-cli-tools:kdesu - Build graphical frontend for kde-frameworks/kdesu
+kde-plasma/kde-gtk-config:gtk3 - Add support for gtk+3-based applications.
+kde-plasma/kdeplasma-addons:dictionary - Enable dictionary applet using dev-qt/qtwebengine
+kde-plasma/kdeplasma-addons:share - Enable applet for quickly sharing data to a variety of sources
+kde-plasma/kinfocenter:gles2 - Show OpenGL ES information in kinfocenter
+kde-plasma/kinfocenter:pci - Show advanced PCI information
+kde-plasma/kmenuedit:hotkeys - Enable support for hotkey editing
+kde-plasma/kscreenlocker:consolekit - Add support for killing the screenlocker when sys-auth/consolekit is the session tracker
+kde-plasma/kwin:gles2 - Use OpenGL ES 2 instead of full GL
+kde-plasma/kwin:multimedia - Enable effect video button in desktop effects KCM
+kde-plasma/libksysguard:detailedmemory - Enable display of detailed memory information using dev-qt/qtwebkit.
+kde-plasma/plasma-desktop:appstream - Enable AppStream software metadata support
+kde-plasma/plasma-desktop:gtk2 - Add support for gtk+2-based applications using legacy xembed systray icons via libappindicator.
+kde-plasma/plasma-desktop:gtk3 - Add support for gtk+3-based applications using legacy xembed systray icons via libappindicator.
+kde-plasma/plasma-desktop:ibus - Use ibus input method via app-i18n/ibus
+kde-plasma/plasma-desktop:legacy-systray - Add support for applications using legacy xembed systray icons.
+kde-plasma/plasma-desktop:mouse - Enable mouse KCM
+kde-plasma/plasma-desktop:scim - Enable applets that use app-i18n/scim
+kde-plasma/plasma-desktop:touchpad - Enable touchpad KCM
+kde-plasma/plasma-meta:crypt - Pull in kde-plasma/plasma-vault for encrypted vaults integration
+kde-plasma/plasma-meta:display-manager - Pull in a graphical display manager
+kde-plasma/plasma-meta:grub - Pull in Breeze theme for sys-boot/grub
+kde-plasma/plasma-meta:gtk - Enable Breeze widget style and KCM for GTK2 and GTK3
+kde-plasma/plasma-meta:legacy-systray - Add support for applications using legacy xembed systray icons, depending on USE qt4 or gtk.
+kde-plasma/plasma-meta:pam - Enable support for kwallet auto-unlocking
+kde-plasma/plasma-meta:plymouth - Pull in Breeze theme for sys-boot/plymouth
+kde-plasma/plasma-meta:pulseaudio - Install Plasma applet for PulseAudio volume management
+kde-plasma/plasma-meta:sddm - Pull in the x11-misc/sddm display manager and KCM
+kde-plasma/plasma-meta:sdk - Pull in kde-plasma/plasma-sdk for Plasma development
+kde-plasma/plasma-meta:wallpapers - Install wallpapers for the Plasma Workspace
+kde-plasma/plasma-nm:modemmanager - Enable support for mobile broadband devices
+kde-plasma/plasma-nm:openconnect - Build support for the OpenConnect VPN client
+kde-plasma/plasma-nm:teamd - Enable Teamd control support
+kde-plasma/plasma-workspace:appstream - Enable AppStream software metadata support
+kde-plasma/plasma-workspace:geolocation - Enables dataengine providing location information
+kde-plasma/plasma-workspace:prison - Enable support for barcodes/QRcodes
+kde-plasma/plasma-workspace:qalculate - Enable Qalculate runner using sci-libs/libqalculate
+kde-plasma/powerdevil:brightness-control - Enable screen brightness control using app-misc/ddcutil
+kde-plasma/powerdevil:consolekit - Enable sys-auth/consolekit support instead of logind session tracking
+kde-plasma/powerdevil:wireless - Enable wireless energy saving actions via kde-frameworks/bluez-qt and kde-frameworks/networkmanager-qt
+kde-plasma/systemsettings:classic - Enable classic mode plugin, requires kde-frameworks/khtml
+lxde-base/lxdm:consolekit - Enables support for authorization using consolekit
+lxde-base/lxdm:gtk3 - Use GTK+3 instead of 2
+lxde-base/lxterminal:gtk3 - Use GTK+3 instead of GTK+2
+lxqt-base/lxqt-meta:about - Install lxqt-base/lxqt-about
+lxqt-base/lxqt-meta:admin - Install lxqt-base/lxqt-admin
+lxqt-base/lxqt-meta:filemanager - Install x11-misc/pcmanfm-qt file manager
+lxqt-base/lxqt-meta:icons - Install an icon theme
+lxqt-base/lxqt-meta:lightdm - Install x11-misc/lightdm display manager
+lxqt-base/lxqt-meta:lximage - Install media-gfx/lximage-qt image viewer
+lxqt-base/lxqt-meta:minimal - Do not install x11-wm/openbox window manager
+lxqt-base/lxqt-meta:oxygen - Prefer kde-frameworks/oxygen-icons (default)
+lxqt-base/lxqt-meta:powermanagement - Install lxqt-base/lxqt-powermanagement package
+lxqt-base/lxqt-meta:sddm - Install x11-misc/sddm display manager
+lxqt-base/lxqt-meta:ssh-askpass - Install lxqt-base/lxqt-openssh-askpass user password prompt tool
+lxqt-base/lxqt-meta:sudo - Install lxqt-base/lxqt-sudo
+lxqt-base/lxqt-panel:clock - Build clock plugin
+lxqt-base/lxqt-panel:colorpicker - Build colorpicker plugin
+lxqt-base/lxqt-panel:cpuload - Build cpuload plugin
+lxqt-base/lxqt-panel:desktopswitch - Build desktopswitch plugin
+lxqt-base/lxqt-panel:dom - Build dom plugin
+lxqt-base/lxqt-panel:kbindicator - Build kbindicator plugin
+lxqt-base/lxqt-panel:mainmenu - Build mainmenu plugin
+lxqt-base/lxqt-panel:mount - Build mount plugin
+lxqt-base/lxqt-panel:networkmonitor - Build networkmonitor plugin
+lxqt-base/lxqt-panel:quicklaunch - Build quicklaunch plugin
+lxqt-base/lxqt-panel:sensors - Build sensors plugin
+lxqt-base/lxqt-panel:showdesktop - Build showdesktop plugin
+lxqt-base/lxqt-panel:statusnotifier - Build statusnotifier plugin
+lxqt-base/lxqt-panel:sysstat - Build sysstat plugin
+lxqt-base/lxqt-panel:taskbar - Build taskbar plugin
+lxqt-base/lxqt-panel:tray - Build tray plugin
+lxqt-base/lxqt-panel:volume - Build volume plugin
+lxqt-base/lxqt-panel:worldclock - Build worldclock plugin
+mail-client/alot:doc - Install user manual and API documentation
+mail-client/alpine:chappa - enhance alpine by applying Eduardo Chappa's patches
+mail-client/alpine:onlyalpine - installs only the alpine binary, so it does not collied with pico and/or pine
+mail-client/alpine:passfile - Adds support for caching passwords into a file between sessions
+mail-client/alpine:smime - Enable support for S/MIME
+mail-client/balsa:crypt - Adds support for GnuPG encryption
+mail-client/balsa:gtkhtml - Use gtkhtml for HTML rendering
+mail-client/balsa:gtkspell - Use gtkspell for dictionary support
+mail-client/balsa:rubrica - Adds support for rubrica addressbook
+mail-client/claws-mail:archive - Enable archiving plugin
+mail-client/claws-mail:bogofilter - Build mail-filter/bogofilter plugin
+mail-client/claws-mail:gdata - Enable plugin for access to Google data providers
+mail-client/claws-mail:gtk3 - Build support for GTK+3
+mail-client/claws-mail:libcanberra - Enable sound notification in connection with USE=notification
+mail-client/claws-mail:libindicate - Enable notification through DBUS in connection with USE=notification
+mail-client/claws-mail:libnotify - Enable notification on the desktop in connection with USE=notification
+mail-client/claws-mail:notification - Notification for new mail in different way, see also USE flags libcanberra, libindicate and libnotify
+mail-client/claws-mail:pgp - Enable PGP support
+mail-client/claws-mail:sieve - Build plugin for sieve filter support
+mail-client/claws-mail:smime - Build plugin for S/MIME support
+mail-client/claws-mail:spam-report - Enable plugin for spam reporting to various services
+mail-client/claws-mail:spamassassin - Build mail-filter/spamassassin plugin
+mail-client/claws-mail:valgrind - Add support for memory debugging using valgrind
+mail-client/evolution:archive - Enable archives support in attachments via app-arch/gnome-autoar
+mail-client/evolution:bogofilter - Build mail-filter/bogofilter plugin
+mail-client/evolution:crypt - Enable GPG encryption support using app-crypt/gnupg and app-crypt/pinentry
+mail-client/evolution:geolocation - Enable support for displaying contacts on a map inside evolution using media-libs/libchamplain
+mail-client/evolution:highlight - Enable text highlighting plugin
+mail-client/evolution:ldap - Enable support for fetching contacts from an LDAP or Active Directory server using net-nds/openldap
+mail-client/evolution:spamassassin - Build mail-filter/spamassassin plugin
+mail-client/evolution:weather - Enable optional weather calendar support
+mail-client/evolution:ytnef - Enable optional TNEF attachments parser support using net-mail/ytnef
+mail-client/mail-notification:sylpheed - Enable support for MH mailboxes used by mail-client/sylpheed
+mail-client/mutt:berkdb - Enable sys-libs/db database backend for header caching
+mail-client/mutt:crypt - Add support for encryption -- using mcrypt or gpg where applicable
+mail-client/mutt:gdbm - Enable sys-libs/gdbm database backend for header caching
+mail-client/mutt:gpg - Enable support for app-crypt/gpgme
+mail-client/mutt:gpgme - Build gpgme backend to support S/MIME, PGP/MIME and traditional/inline PGP
+mail-client/mutt:hcache - Enable header cache, one database backend needs to be enabled
+mail-client/mutt:lmdb - Enable dev-db/lmdb database backend for header caching
+mail-client/mutt:notmuch - Enable support for net-mail/notmuch
+mail-client/mutt:pgp_classic - Build classic_pgp backend to support PGP/MIME and traditional/inline PGP
+mail-client/mutt:pop - Enable support for POP3 mailboxes
+mail-client/mutt:sidebar - Enable the sidebar feature
+mail-client/mutt:smime - Enable support for smime
+mail-client/mutt:smime_classic - Build classic_smime backend to support S/MIME
+mail-client/mutt:smtp - Enable support for direct SMTP delivery
+mail-client/mutt:tokyocabinet - Enable dev-db/tokyocabinet database backend for header caching
+mail-client/nail:kerberos - If network is enabled, this adds support for GSSAPI login on IMAP through virtual/krb5.
+mail-client/nail:net - Enable support for network protocols (POP, IMAP and SMTP). If you only need to send mail with the local Transport Agent, disabling this will get you support for only /usr/sbin/sendmail call.
+mail-client/nail:ssl - If network is enabled, this adds support for S/MIME and SSL/TLS-powered protocols through dev-libs/openssl.
+mail-client/neomutt:berkdb - Enable BDB (Berkley DB) backend for header caching
+mail-client/neomutt:crypt - Add support for encryption -- using mcrypt or gpg where applicable
+mail-client/neomutt:gdbm - Enable GDBM (GNU dbm) backend for header caching
+mail-client/neomutt:gpg - Enable support for app-crypt/gpgme
+mail-client/neomutt:gpgme - Build gpgme backend to support S/MIME, PGP/MIME and traditional/inline PGP
+mail-client/neomutt:kyotocabinet - Enable Kyoto Cabinet database backend for header caching
+mail-client/neomutt:lmdb - Enable LMDB (Lightning Memory-Mapped Database) backend for header caching
+mail-client/neomutt:notmuch - Enable support for net-mail/notmuch
+mail-client/neomutt:pgp_classic - Build classic_pgp backend to support PGP/MIME and traditional/inline PGP
+mail-client/neomutt:qdbm - Enable QDBM (Quicker Database Manager) database backend for header caching
+mail-client/neomutt:smime - Enable support for smime
+mail-client/neomutt:smime_classic - Build classic_smime backend to support S/MIME
+mail-client/neomutt:tokyocabinet - Enable Tokyo Cabinet database backend for header caching
+mail-client/roundcube:enigma - Add dependencies to support server-side GnuPG signing and/or encryption through the enigma plugin
+mail-client/roundcube:ldap - Add dependencies to support connecting to an LDAP address book server
+mail-client/roundcube:managesieve - Add dependencies to support the sieverules plugin
+mail-client/sylpheed:oniguruma - Use dev-libs/oniguruma for regular expression
+mail-client/thunderbird:bindist - Disable official Thunderbird branding (icons, name) which are not binary-redistributable according to upstream.
+mail-client/thunderbird:crypt - Enable encryption support with enigmail
+mail-client/thunderbird:custom-optimization - Build with user-specified compiler optimizations (-Os, -O0, -O1, -O2, -O3) from CFLAGS (unsupported)
+mail-client/thunderbird:gtk2 - Use the cairo-gtk2 rendering engine instead of the default cairo-gtk3
+mail-client/thunderbird:jemalloc - Enable or disable jemalloc
+mail-client/thunderbird:jemalloc3 - Enable or disable jemalloc3 (forced-on when supported prior to 38.0)
+mail-client/thunderbird:lightning - Enable app-global calendar support (note 38.0 and above bundles calendar support when this flag is off)
+mail-client/thunderbird:minimal - Remove the software development kit and headers
+mail-client/thunderbird:mozdom - Enable Mozilla's DOM inspector
+mail-client/thunderbird:rust - Enable support for using rust compiler (experimental)
+mail-client/thunderbird:system-cairo - Use the system-wide x11-libs/cairo instead of bundled.
+mail-client/thunderbird:system-harfbuzz - Use the system-wide media-libs/harfbuzz and media-gfx/graphite2 instead of bundled.
+mail-client/thunderbird:system-icu - Use the system-wide dev-libs/icu instead of bundled.
+mail-client/thunderbird:system-jpeg - Use the system-wide media-libs/libjpeg-turbo instead of bundled.
+mail-client/thunderbird:system-libevent - Use the system-wide dev-libs/libevent instead of bundled.
+mail-client/thunderbird:system-libvpx - Use the system-wide media-libs/libvpx instead of bundled.
+mail-client/thunderbird:system-sqlite - Use the system-wide dev-db/sqlite installation with secure-delete enabled
+mail-client/thunderbird-bin:crashreporter - Enable crash reporter for bugs
+mail-client/trojita:password - Store passwords securely via dev-libs/qtkeychain
+mail-filter/MailScanner:exim - Set mail-mta/exim to used MTA
+mail-filter/MailScanner:postfix - Set mail-mta/postfix to used MTA
+mail-filter/MailScanner:spamassassin - Enable usage of mail-filter/spamassassin for spam protection
+mail-filter/amavisd-new:courier - Add courier support
+mail-filter/amavisd-new:dkim - Add DomainKeys Identified Mail support
+mail-filter/amavisd-new:qmail - Add qmail support
+mail-filter/amavisd-new:razor - Add support for mail-filter/razor
+mail-filter/amavisd-new:spamassassin - Add support for mail-filter/spamassassin
+mail-filter/amavisd-new:zmq - Add support for zeromq sockets
+mail-filter/ask:procmail - Adds support for mail-filter/procmail
+mail-filter/assp:spf - Adds support for Sender Policy Framework
+mail-filter/assp:srs - Adds support for Sender Rewriting Scheme
+mail-filter/bogofilter:tokyocabinet - Enable Tokyo Cabinet database support
+mail-filter/clamassassin:clamd - Use the app-antivirus/clamav daemon for virus checking
+mail-filter/clamassassin:subject-rewrite - Adds support for subject rewriting
+mail-filter/dcc:rrdtool - Enable net-analyzer/rrdtool interface scripts
+mail-filter/dspam:daemon - Enable support for DSPAM to run in --daemon mode
+mail-filter/dspam:debug - Enable debugging support (don't enable this unless something needs testing!)
+mail-filter/dspam:domain-scale - Build for domain scale setups - puts data to $HOME/data/domain.com/user
+mail-filter/dspam:hash - Enable support for the file-orientated hash driver
+mail-filter/dspam:large-scale - Build for large scale setups - puts data to $HOME/data/u/s/user
+mail-filter/dspam:small-scale - Build for small scale setups - puts data to $HOME/data/user
+mail-filter/dspam:user-homedirs - Build with user homedir support
+mail-filter/dspam:virtual-users - Build with virtual-users support
+mail-filter/libmilter:poll - Use poll instead of select
+mail-filter/maildrop:authlib - Add courier-authlib support
+mail-filter/maildrop:dovecot - Add dovecot authentication support
+mail-filter/maildrop:tools - Install maildirmake and deliverquota tools
+mail-filter/maildrop:trashquota - Count deleted messages as part of the maildir quota
+mail-filter/mimedefang:poll - Use poll instead of select
+mail-filter/opendkim:ldap - Enable openldap as a dataset facilitator or keys, determining domains to sign for, and any other dataset that opendkim supports.
+mail-filter/opendkim:lmdb - Add support for using dev-db/lmdb
+mail-filter/opendkim:lua - Enables control over signature verification, filtering and policy to be controlled by user defined lua scripts.
+mail-filter/opendkim:memcached - Add support for using dev-libs/libmemcached
+mail-filter/opendkim:opendbx - Use opendbx backend to facilitate dataset driven OpenDKIM configuration options like stats, bodylengthdb, etc. against a wide variety of database types
+mail-filter/opendkim:poll - Use poll() instead of select() for the provided asynchronous resolver library.
+mail-filter/opendkim:sasl - Used to authenticate to a LDAP server in various ways if required.
+mail-filter/opendkim:unbound - Use the unbound dnssec library to perform DKIM DNS queries.
+mail-filter/opendmarc:reports - Install the reports binaries: expire, import, reports, params
+mail-filter/opendmarc:spf - Use the mail-filter/libspf2 for Sender Policy Framework checking
+mail-filter/opensmtpd-extras:filter-clamav - filter for scanning with app-antivirus/clamav
+mail-filter/opensmtpd-extras:filter-dkim-signer - filter for adding DKIM signatures to outgoing messages
+mail-filter/opensmtpd-extras:filter-dnsbl - filter for checking hosts against the DNS black lists
+mail-filter/opensmtpd-extras:filter-lua - filter for interfacing with dev-lang/lua
+mail-filter/opensmtpd-extras:filter-monkey - filter for arbitrarily rejecting random emails
+mail-filter/opensmtpd-extras:filter-pause - filter to pause on new connections
+mail-filter/opensmtpd-extras:filter-perl - filter for interfacing with dev-lang/perl
+mail-filter/opensmtpd-extras:filter-python - filter for interfacing with dev-lang/python
+mail-filter/opensmtpd-extras:filter-regex - filter for regular expression matching
+mail-filter/opensmtpd-extras:filter-spamassassin - filter for scanning with mail-filter/spamassassin
+mail-filter/opensmtpd-extras:filter-stub - stub filter
+mail-filter/opensmtpd-extras:filter-trace - trace filter
+mail-filter/opensmtpd-extras:filter-void - void filter
+mail-filter/opensmtpd-extras:luajit - Use JIT for Lua via dev-lang/luajit instead of dev-lang/lua
+mail-filter/opensmtpd-extras:queue-null - null queue
+mail-filter/opensmtpd-extras:queue-python - queue for interfacing with dev-lang/python
+mail-filter/opensmtpd-extras:queue-ram - ram queue
+mail-filter/opensmtpd-extras:queue-stub - stub queue
+mail-filter/opensmtpd-extras:scheduler-python - schedulre for interfacing with python
+mail-filter/opensmtpd-extras:scheduler-ram - ram scheduler
+mail-filter/opensmtpd-extras:scheduler-stub - stub scheduler
+mail-filter/opensmtpd-extras:table-ldap - table for lookups with net-nds/openldap
+mail-filter/opensmtpd-extras:table-mysql - table for lookups with virtual/mysql
+mail-filter/opensmtpd-extras:table-passwd - table for lookups using /etc/passwd
+mail-filter/opensmtpd-extras:table-postgres - table for lookups with dev-db/postgresql
+mail-filter/opensmtpd-extras:table-python - table for interfacing with dev-lang/python
+mail-filter/opensmtpd-extras:table-redis - table for lookups with dev-db/redis
+mail-filter/opensmtpd-extras:table-socketmap - table for lookups using a socket map
+mail-filter/opensmtpd-extras:table-sqlite - table for lookups with dev-db/sqlite3
+mail-filter/opensmtpd-extras:table-stub - stub table
+mail-filter/postfwd:tools - Install additional tools for testing postfwd
+mail-filter/postgrey:targrey - Enables the targrey patch
+mail-filter/qmail-scanner:spamassassin - Build faster mail-filter/spamassassin checks into qmail-scanner
+mail-filter/rmilter:dkim - Enable support for DomainKeys Identified Mail
+mail-filter/rmilter:memcached - Enable support for memcached
+mail-filter/rspamd:fann - Enable neural network plugin (requires sci-mathematics/fann).
+mail-filter/rspamd:jemalloc - Use dev-libs/jemalloc for allocations
+mail-filter/rspamd:pcre2 - Use dev-libs/libpcre2
+mail-filter/spamassassin:bayes - Require a database (MySQL, SQLite, Postgres, or BerkDB) backend to enable the Bayesian filtering database. If you use the Redis backend, you do not need to enable this flag (Redis support is enabled automatically, and has no external dependencies).
+mail-filter/spamassassin:cron - Install a cron job to update SpamAssassin's rules daily.
+mail-filter/spamassassin:qmail - Build qmail functionality and docs
+mail-filter/spamdyke:ssl - Enables TLS protocol for spamdyke
+mail-filter/zdkimfilter:debug - Log process and signal information. Also leave the child process running for gdb examination.
+mail-filter/zdkimfilter:opendbx - An alternate statistics based storage engine.
+mail-mta/courier:fax - Enables fax support in the courier mail server
+mail-mta/courier:norewrite - Prevents courier mail server from mangling virtual user addresses when sending
+mail-mta/courier:web - Enable the web interface
+mail-mta/courier:webmail - Enable the webmail interface
+mail-mta/exim:dane - Adds support for DNS-based Authentication of Named Entities
+mail-mta/exim:dcc - Adds support for Distributed Checksum Clearinghouse (DCC)
+mail-mta/exim:dkim - Adds support for DomainKeys Identified Mail (DKIM)
+mail-mta/exim:dlfunc - Install local_scan.h header to compile separate dlfunc libraries
+mail-mta/exim:dmarc - Adds support for DMARC
+mail-mta/exim:dnsdb - Adds support for a DNS search for a record whose domain name is the supplied query
+mail-mta/exim:dovecot-sasl - Adds support for Dovecot's authentication
+mail-mta/exim:dsn - Adds support for Delivery Status Notifications (DSN)
+mail-mta/exim:exiscan-acl - Patch providing support for content scanning
+mail-mta/exim:lmtp - Adds support for lmtp
+mail-mta/exim:mbx - Adds support for UW's mbx format
+mail-mta/exim:pkcs11 - Require pkcs11 support in net-libs/gnutls with USE=gnutls
+mail-mta/exim:prdr - Adds support for Per-Recipient Data Response
+mail-mta/exim:proxy - Add support for being behind a proxy, such as HAProxy
+mail-mta/exim:redis - Adds support for querying dev-db/redis
+mail-mta/exim:spf - Adds support for Sender Policy Framework
+mail-mta/exim:srs - Adds support for Sender Rewriting Scheme
+mail-mta/exim:tpda - Adds support for Transport Post-Delivery Actions
+mail-mta/msmtp:libsecret - Enable libsecret support to store login credentials
+mail-mta/msmtp:mta - Enable this to install as system-wide MTA
+mail-mta/netqmail:authcram - Enable AUTHCRAM support
+mail-mta/netqmail:gencertdaily - Generate SSL certificates daily instead of hourly
+mail-mta/netqmail:highvolume - Prepare netqmail for high volume servers
+mail-mta/opensmtpd:mta - Enable this to install as system-wide MTA
+mail-mta/postfix:dovecot-sasl - Enable net-mail/dovecot protocol version 1 (server only) SASL implementation
+mail-mta/postfix:eai - Add support for SMTPUTF8
+mail-mta/postfix:ldap-bind - Add support for binding to LDAP backend using dev-libs/cyrus-sasl
+mail-mta/postfix:lmdb - Add support for using dev-db/lmdb for lookup tables
+mail-mta/postfix:memcached - Add support for using net-misc/memcached for lookup tables
+mail-mta/postfix:vda - Add support for virtual delivery agent quota enforcing
+mail-mta/qmail-ldap:cluster - Enable this if you want to have cluster support in qmail-ldap
+mail-mta/qmail-ldap:gencertdaily - Generate SSL certificates daily instead of hourly
+mail-mta/qmail-ldap:highvolume - Prepare qmail for high volume servers
+mail-mta/qmail-ldap:rfc2307 - Add support for RFC2307 compliant uid/gid attributes
+mail-mta/qmail-ldap:rfc822 - Add support for RFC822 compliant mail attributes
+mail-mta/qpsmtpd:postfix - create user with permissions for proper postfix interaction
+mail-mta/ssmtp:mta - Install symlinks for sendmail-compatible MTA.
+mate-base/caja:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/caja:mate - Install x11-themes/mate-icon-theme which is needed when this package is used in the MATE desktop environment.
+mate-base/caja:packagekit - Enable support for installing via app-admin/packagekit based on mimetype
+mate-base/libmatekbd:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate:base - Install base MATE Desktop applications that are recommended for the most common usage; for example, this installs the file manager. Disable this and other USE flags if you want a more minimal MATE Desktop.
+mate-base/mate:extras - Install additional MATE Desktop applications that are recommended for extended usage of the MATE Desktop as upstream sees it; for example, this installs MATE Desktop's office related applications. Disable this if you plan to use your own non-MATE Desktop alternatives or a custom mixture of MATE and non-MATE packages.
+mate-base/mate:gtk3 - Build all of MATE DE with GTK+3 instead of GTK+2
+mate-base/mate:help - Install gnome-extra/yelp to handle in application help menus and documentation browsing
+mate-base/mate:notification - Force notification daemon to default to MATE's notification daemon. Enabled by default. Disable if it causes conflicts with other installed desktop environments.
+mate-base/mate:themes - Install MATE Desktop's themes; if you use other themes, you can disable this to spare some space and time.
+mate-base/mate-applets:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate-applets-meta:appindicator - Pull in mate-extra/mate-indicator-applet for AppIndicator applet
+mate-base/mate-applets-meta:gtk3 - Make sure applets are built with GTK+3 instead of GTK+2
+mate-base/mate-applets-meta:netspeed - Pull in net-analyzer/mate-netspeed for net speed monitoring applet
+mate-base/mate-applets-meta:sensors - Pull in mate-extra/mate-sensors-applet for hw sensors applet
+mate-base/mate-control-center:appindicator - Add support for AppIndicator
+mate-base/mate-control-center:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate-desktop:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate-panel:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate-session-manager:gtk3 - Build with GTK+3 instead of GTK+2
+mate-base/mate-session-manager:xtrans - Build with Xtrans support; WARNING: Disabling this flag will result in ICE binding on all interfaces
+mate-base/mate-settings-daemon:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/caja-extensions:cdr - Add an extension to burn files to cds using app-cdr/brasero.
+mate-extra/caja-extensions:gajim - Add an extension to support net-im/gajim.
+mate-extra/caja-extensions:gksu - Add an extension to support opening files as root with x11-libs/gksu.
+mate-extra/caja-extensions:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/caja-extensions:image-converter - Add image conversion support.
+mate-extra/caja-extensions:mail - Add an extension to support e-mail functionality.
+mate-extra/caja-extensions:open-terminal - Add an extension to support an open terminal.
+mate-extra/caja-extensions:pidgin - Add an extension to support net-im/pidgin
+mate-extra/caja-extensions:share - Add an extension to support sharing files.
+mate-extra/caja-extensions:wallpaper - Add an extension to support setting an image as the current wallpaper
+mate-extra/mate-indicator-applet:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-media:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-netbook:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-polkit:accountsservice - Support extraction of data from AccountsService
+mate-extra/mate-polkit:appindicator - Add support for AppIndicator
+mate-extra/mate-polkit:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-power-manager:applet - Enable building of the MATE applet.
+mate-extra/mate-power-manager:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-power-manager:man - Build power manager's man page.
+mate-extra/mate-power-manager:pm-utils - Adds support for suspend/resume using sys-power/upower-pm-utils instead of sys-power/upower
+mate-extra/mate-screensaver:consolekit - Enable support for sys-auth/consolekit
+mate-extra/mate-screensaver:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-sensors-applet:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-system-monitor:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-user-share:gtk3 - Build with GTK+3 instead of GTK+2
+mate-extra/mate-utils:applet - Enable the mate dictionary applet
+mate-extra/mate-utils:gtk3 - Build with GTK+3 instead of GTK+2
+media-fonts/corefonts:tahoma - Also install the Tahoma font. Due to the lack of a free bold variant, this may render badly. See bug 184790.
+media-fonts/culmus:ancient - Install ancient semitic scripts
+media-fonts/culmus:fancy - Install fancy fonts
+media-fonts/culmus:fontforge - Use media-gfx/fontforge to build fonts from source
+media-fonts/culmus:taamey - Install taamey fonts
+media-fonts/dejavu:fontforge - Use media-gfx/fontforge to build fonts from source
+media-fonts/fontawesome:otf - Install the OpenType version of the font
+media-fonts/fontawesome:ttf - Install the TrueType version of the font
+media-fonts/infinality-ultimate-meta:free - Install fonts for the "free" preset
+media-fonts/infinality-ultimate-meta:latin - Install additional latin fonts
+media-fonts/infinality-ultimate-meta:minimal - Install a minimal set of fonts
+media-fonts/infinality-ultimate-meta:ms - Install (free) fonts for the "ms" preset
+media-fonts/intlfonts:bdf - Installs BDF fonts in addition to PCF
+media-fonts/liberation-fonts:fontforge - Use media-gfx/fontforge to build fonts from source
+media-fonts/montecarlo:bdf - Install BDF fonts in addition to PCF
+media-fonts/mplus-outline-fonts:ipafont - Generates new fonts merged with media-fonts/ja-ipafonts
+media-fonts/sil-charis:compact - Use more compactly spaced font
+media-fonts/sil-gentium:compact - Also install more compact version of the font.
+media-fonts/terminus-font:a-like-o - Changes view of letter 'a' - a looks like o (see homepage)
+media-fonts/terminus-font:center-tilde - Place the '~' character vertically centered on the line instead of to the top.
+media-fonts/terminus-font:distinct-l - ll2 variant with more distinctive l (lowercase L)
+media-fonts/terminus-font:pcf - Install Portable Compiled Font (PCF) (required for X11)
+media-fonts/terminus-font:pcf-unicode-only - Remove non-unicode PCF fonts that could be problematic. See bug #520222.
+media-fonts/terminus-font:psf - Install PC Screen Font (PSF) with unicode data (for linux console)
+media-fonts/terminus-font:quote - Changes view of quotes: symmetric ` and ' instead of asymmetric one (see homepage)
+media-fonts/terminus-font:raw-font-data - Install RAW font data which should be compatible with most UNIX systems (you don't need this on linux)
+media-fonts/terminus-font:ru-dv - Changes view of Russian letters 'de' and 've' (see homepage)
+media-fonts/terminus-font:ru-g - Changes view of Russian letter 'ge' (see homepage)
+media-fonts/terminus-font:ru-i - Changes view of Russian letter 'i' - not like Latin u, but like "mirrored" N (see homepage)
+media-fonts/terminus-font:ru-k - Changes view of Russian letter 'k' (see homepage)
+media-fonts/unifont:fontforge - Use media-gfx/fontforge to build fonts from source
+media-fonts/unifont:utils - Install unifont utilities
+media-gfx/album:plugins - Install optional plugins
+media-gfx/album:themes - Install optional themes
+media-gfx/alembic:boost - Use dev-libs/boost library
+media-gfx/alembic:hdf5 - Add support sci-libs/hdf5
+media-gfx/alembic:pyalembic - Build pyalembic python bindings (needs dev-python/pyilmbase)
+media-gfx/alembic:test - Build and run the test-suite
+media-gfx/alembic:zlib - Use sys-libs/zlib for compressions
+media-gfx/apngasm:7z - Enable support for 7zip compression
+media-gfx/apngasm:zopfli - Enable support for Zopfli compression
+media-gfx/asymptote:boehm-gc - Enables using the Boehm-Demers-Weiser conservative garbage collector
+media-gfx/asymptote:offscreen - Enables off-screen rendering
+media-gfx/asymptote:sigsegv - Enables using dev-libs/libsigsegv
+media-gfx/blender:boost - Enable features depending on boost.
+media-gfx/blender:bullet - Enable Bullet (Physics Engine).
+media-gfx/blender:collada - Add support for Collada interchange format through media-libs/opencollada.
+media-gfx/blender:colorio - Enable OpenColorIO color management through media-libs/opencolorio.
+media-gfx/blender:cuda - Build cycles renderer with nVidia CUDA support.
+media-gfx/blender:cycles - Build cycles renderer (requires media-libs/openimageio and dev-libs/boost).
+media-gfx/blender:dds - Adds DDS textures support to Blender.
+media-gfx/blender:doc - Build C and Python API documentation directly from the source code.
+media-gfx/blender:elbeem - Adds surface fluid simulation to Blender using El'Beem library.
+media-gfx/blender:game-engine - Adds Game Engine support to Blender.
+media-gfx/blender:headless - Build without graphical support (renderfarm, server mode only).
+media-gfx/blender:jemalloc - Use dev-libs/jemalloc for memory allocation.
+media-gfx/blender:llvm - Enable features depending on llvm.
+media-gfx/blender:man - Build and install man pages.
+media-gfx/blender:ndof - Enable NDOF input devices (SpaceNavigator and friends).
+media-gfx/blender:opencl - Allow OpenCL Graphics Acceleration. This may require extra graphics card drivers.
+media-gfx/blender:openimageio - Enable OpenImageIO Support
+media-gfx/blender:opennl - Enable use of Open Numerical Library
+media-gfx/blender:opensubdiv - Add rendering support form OpenSubdiv from Dreamworks Animation through media-libs/opensubdiv.
+media-gfx/blender:openvdb - Add GPU preview rendering. Only works with nVidia cards.
+media-gfx/blender:osl - Add support for OpenShadingLanguage scripting.
+media-gfx/blender:player - Build the Blender Player. THis requires the Game engine.
+media-gfx/blender:redcode - This flag add support for RED CODE camera digital format (5K HD images *.r3d) - EXPERIMENTAL.
+media-gfx/blender:test - Build the provided unit tests.
+media-gfx/blender:valgrind - Add support for memory debugging using dev-util/valgrind
+media-gfx/comix:rar - Pulls app-arch/unrar for rar file support
+media-gfx/cura:usb - Access 3D printers via USB
+media-gfx/darktable:colord - Support color management using x11-misc/colord
+media-gfx/darktable:flickr - Add support for uploading photos to flickr
+media-gfx/darktable:geo - Enable geotagging support
+media-gfx/darktable:kwallet - Enable encrypted storage of passwords with kde-frameworks/kwallet
+media-gfx/darktable:libsecret - Enable libsecret support to store login credentials
+media-gfx/darktable:opencl - Enable opencl support
+media-gfx/darktable:pax_kernel - Triggers paxmarking of main darktable binary
+media-gfx/darktable:webp - Enable WebP export support
+media-gfx/digikam:addressbook - Enable akonadi contact integration
+media-gfx/digikam:kipi - Enable support for media-plugins/kipi-plugins
+media-gfx/digikam:lensfun - Enable support for media-libs/lensfun
+media-gfx/digikam:marble - Enable support for geolocation using kde-apps/marble
+media-gfx/digikam:mediaplayer - Enable support for media player using media-libs/qtav
+media-gfx/digikam:panorama - Build the panorama plugin which requires media-gfx/hugin
+media-gfx/digikam:semantic-desktop - Enable kde-frameworks/kfilemetadata support
+media-gfx/enblend:gpu - GPU support for Enblend
+media-gfx/enblend:image-cache - allow for processing of large images
+media-gfx/eog-plugins:flickr - Enable uploading to Flickr
+media-gfx/eog-plugins:map - Enable world map display using media-libs/libchamplain
+media-gfx/eog-plugins:picasa - Enable uploading to Google's Picasa Web Albums
+media-gfx/eom:gtk3 - Build with GTK+3 instead of GTK+2
+media-gfx/exact-image:swig - Adds Swig support dev-lang/swig
+media-gfx/exiv2:webready - Support reading metadata over the internet
+media-gfx/fbida:X - Install the Motif based image viewer "ida"
+media-gfx/fbida:fbcon - Install the framebuffer image viewer "fbi"
+media-gfx/fbida:ghostscript - Install the framebuffer ghostscript viewer "fbgs"
+media-gfx/fbida:webp - Enable support for the WebP image format
+media-gfx/fim:dia - Enable DIA file support via app-office/dia
+media-gfx/fim:imagemagick - Use convert from media-gfx/imagemagick as fallback file opener
+media-gfx/fim:xfig - Enable FIG file support via media-gfx/xfig
+media-gfx/fontforge:truetype-debugger - Enable truetype debugger in fontforge
+media-gfx/fotowall:webcam - Enable webcam support
+media-gfx/freewrl:glew - Enable glew extensions
+media-gfx/freewrl:java - Build and install java EAI/SAI support library
+media-gfx/freewrl:libeai - Build EAI C library
+media-gfx/freewrl:opencl - Enable OpenCL support
+media-gfx/freewrl:osc - Allows for OSC-based control and communication between multiple freewrl instances
+media-gfx/freewrl:rbp - Enable support for Rigid Body Physics
+media-gfx/geeqie:ffmpegthumbnailer - Enable video thumbnail support with media-video/ffmpegthumbnailer
+media-gfx/geeqie:gpu-accel - Enable GPU acceleration support - experimental
+media-gfx/geeqie:gtk3 - Link against x11-libs/gtk+:3 instead of x11-libs/gtk+:2
+media-gfx/geeqie:map - Enable items map display - experimental
+media-gfx/gimp:smp - Enable support for multiprocessors
+media-gfx/gimp:vector-icons - Enable support for vector icons (experimental)
+media-gfx/gmic:cli - Build CLI interface
+media-gfx/gmic:opencv - Enable support for webcams using the OpenCV library
+media-gfx/gnome-photos:flickr - Ensure runtime Flickr support
+media-gfx/graphicsmagick:fpx - Enable FlashPix support with media-libs/libfpx
+media-gfx/graphicsmagick:modules - Compile graphicsmagick with dynamically loadable modules
+media-gfx/graphicsmagick:q16 - Set storage quantum size to 16 (~2*memory)
+media-gfx/graphicsmagick:q32 - Set storage quantum size to 32 (~5*memory)
+media-gfx/graphicsmagick:webp - Enable support for webp image format
+media-gfx/graphviz:X - Builds lefty front-end, builds plugin -Txlib, and enables support for x11 in various other modules (needs cairo)
+media-gfx/graphviz:devil - Enables DevIL output plugin -Tdevil
+media-gfx/graphviz:gdk-pixbuf - Enables gdk-pixbuf2 plugin
+media-gfx/graphviz:gtk - Enables gtk+ output plugin -Tgtk (needs cairo)
+media-gfx/graphviz:gts - Enables support for gts
+media-gfx/graphviz:lasi - Enables PostScript output via media-libs/lasi, for plugin -Tlasi (needs cairo)
+media-gfx/graphviz:qt4 - Builds gvedit front-end
+media-gfx/gthumb:http - Enable webservice integration through net-libs/libsoup
+media-gfx/gthumb:json - Compile code that uses the libjson-glib library
+media-gfx/gthumb:slideshow - Enable slideshow plugin
+media-gfx/gthumb:webp - Enable support for webp image format
+media-gfx/hugin:sift - automatically align images with media-gfx/autopano-sift-C
+media-gfx/imagemagick:corefonts - Use media-fonts/corefonts which is required by some commands
+media-gfx/imagemagick:fpx - Enable media-libs/libfpx support
+media-gfx/imagemagick:hdri - enable High Dynamic Range Images formats
+media-gfx/imagemagick:lqr - Enable experimental liquid rescale support using media-libs/liblqr
+media-gfx/imagemagick:opencl - Enable OpenCL support
+media-gfx/imagemagick:pango - Enable Pango support using x11-libs/pango
+media-gfx/imagemagick:q32 - Set quantum depth value to 32
+media-gfx/imagemagick:q8 - Set quantum depth value to 8
+media-gfx/imagemagick:webp - Enable webp image format support using media-libs/libwebp
+media-gfx/imageworsener:webp - enable webp image format support
+media-gfx/inkscape:cdr - Enable support for CorelDRAW Diagrams
+media-gfx/inkscape:dia - pull in app-office/dia for dia import extension
+media-gfx/inkscape:inkjar - Enable support for OpenOffice.org SVG jar files
+media-gfx/inkscape:latex - pull in dependencies for LaTeX formulas
+media-gfx/inkscape:visio - Enable support for Microsoft Visio Diagrams
+media-gfx/inkscape:wpg - Enable support for WordPerfect Graphics
+media-gfx/iscan-plugin-gt-f500:minimal - Install the firmware only, and not the plugin.
+media-gfx/jpeg2ps:metric - Default to A4 paper size
+media-gfx/k3d:3ds - Enable support for 3D Studio models
+media-gfx/k3d:cuda - Use nvidia cuda toolkit for speeding up computations
+media-gfx/k3d:gts - Add Support for the GNU Triangulated Surface Library sci-libs/gts
+media-gfx/kphotoalbum:kipi - Support for the KDE Image Plugin Interface
+media-gfx/kphotoalbum:map - Enable map display support using kde-apps/libkgeomap
+media-gfx/krita:color-management - Enable color management via media-libs/opencolorio
+media-gfx/krita:qtmedia - Enable sound support for animations via dev-qt/qtmultimedia
+media-gfx/krita:vc - Enable support for dev-libs/vc, could be a significant speed boost
+media-gfx/librecad:3d - Require all 2D coordinates stored as 3D
+media-gfx/librecad:tools - Build additional tool programs: tff2lff
+media-gfx/luminance-hdr:fits - Enable support for the FITS format
+media-gfx/mandelbulber:opencl - Enable GPU rendering support using OpenCL
+media-gfx/nomacs:opencv - Build support for media-libs/opencv
+media-gfx/nomacs:zip - Build support for zip archives
+media-gfx/nvidia-texture-tools:cg - Enable NVIDIA C graphics compiler toolkit plug-in
+media-gfx/nvidia-texture-tools:cuda - Enable NVIDIA CUDA toolkit support
+media-gfx/nvidia-texture-tools:glew - Enable support for The OpenGL Extension Wrangler Library (media-libs/glew)
+media-gfx/openclipart:gzip - Compresses clip art using gzip
+media-gfx/openexr_viewers:cg - Add support for nvidia's cg shaders
+media-gfx/openvdb:abi3-compat - Enables compatibility with the old 3.x ABI. enabled by dfault.
+media-gfx/openvdb:openvdb-compression - Adds enhanced compression to files through dev-libs/c-blosc. Very useful so enabled by dfault.
+media-gfx/photoqt:exiv2 - Use media-gfx/exiv2 as optional dependency
+media-gfx/pngcrush:system-libs - Use libpng and libz provided by system
+media-gfx/potrace:metric - default to a4 paper size and metric measurement
+media-gfx/povray:io-restrictions - POV-Ray's mechanism for control of I/O operations
+media-gfx/povray:mkl - Enable support for Intel Vector Math Library, part of sci-libs/mkl
+media-gfx/pqiv:archive - Enable support for images in archives and cbX comic book files
+media-gfx/pstoedit:emf - Enable media-libs/libemf support
+media-gfx/pstoedit:flash - Enable media-libs/ming SWF support
+media-gfx/pstoedit:pptx - Enable support for generating PowerPoint pptx files
+media-gfx/qiv:magic - Use libmagic to determine mimetypes
+media-gfx/qiviewer:webp - Build support for WEBP image format
+media-gfx/sigal:s3 - Enables support for the Amazon S3 service.
+media-gfx/simple-scan:colord - Support color management using x11-misc/colord
+media-gfx/slic3r:gui - Enable GUI
+media-gfx/splashutils:fbcondecor - Support for the fbcondecor kernel patch.
+media-gfx/ufraw:contrast - enable contrast setting option
+media-gfx/ufraw:fits - Enable support for the FITS image format through sci-libs/cfitsio
+media-gfx/ufraw:timezone - enable DST correction for file timestamps
+media-gfx/xpaint:pgf - Support for loading PGF images
+media-gfx/xsane:ocr - Enable support for Optical Character Recognition reader
+media-gfx/yafaray:blender - install media-gfx/blender scripts
+media-libs/a52dec:djbfft - Prefer D.J. Bernstein's library for fourier transforms
+media-libs/allegro:dumb - Enable media-libs/dumb module library support
+media-libs/allegro:physfs - Enable physfs support
+media-libs/allegro:vga - Enables the VGA graphics driver
+media-libs/alsa-lib:alisp - Enable support for ALISP (ALSA LISP) interpreter for advanced features.
+media-libs/alure:dumb - Enable media-libs/dumb module library support
+media-libs/alure:fluidsynth - Enables Fluidsynth MIDI software synthesis
+media-libs/assimp:boost - Build assimp with boost support
+media-libs/assimp:samples - Build viewer library
+media-libs/assimp:tools - Build assimp tool binary
+media-libs/aubio:double-precision - Compile in double precision mode.
+media-libs/avidemux-core:nvenc - Adds support for NVIDIA Encoder (NVENC) API for hardware accelerated encoding on NVIDIA cards.
+media-libs/avidemux-core:system-ffmpeg - Use the ffmpeg provided by the system.
+media-libs/avidemux-plugins:aften - Enable A/52 (AC-3) audio encoder support.
+media-libs/avidemux-plugins:amr - Enable Adaptive Multi-Rate format support via media-libs/opencore-amr.
+media-libs/avidemux-plugins:dcaenc - Enable DTS Coherent Acoustics audio encoder support via media-sound/dcaenc.
+media-libs/avidemux-plugins:fdk - Adds support for encoding AAC using media-libs/fdk-aac.
+media-libs/avidemux-plugins:fribidi - Enable unicode bidirectional algorithm support via dev-libs/fribidi.
+media-libs/avidemux-plugins:nvenc - Adds support for NVIDIA Encoder (NVENC) API for hardware accelerated encoding on NVIDIA cards.
+media-libs/avidemux-plugins:opus - Adds support for the Opus codec via media-libs/opus.
+media-libs/avidemux-plugins:twolame - Enable TwoLAME support via media-sound/twolame, an optimised MPEG Audio Layer 2 (MP2) encoder.
+media-libs/avidemux-plugins:vpx - Enable WebM VP8 Codec SDK support via media-libs/libvpx.
+media-libs/avidemux-plugins:x265 - Enables HEVC support with media-libs/x265.
+media-libs/babl:cpu_flags_x86_f16c - Take advantage of CPU feature f16c
+media-libs/cal3d:16bit-indices - Enables use of 16bit indices
+media-libs/chromaprint:tools - Build and install fpcalc and fpcollect tools
+media-libs/clutter:egl - Enable EGL backend.
+media-libs/clutter:gtk - Use gdk-pixbuf from x11-libs/gtk+ as image rendering backend
+media-libs/cogl:gles2 - Enable OpenGL ES 2.0 support
+media-libs/cogl:kms - Enable KMS support.
+media-libs/cogl:pango - Build cogl-pango library for x11-libs/pango integration
+media-libs/coin:simage - Texture loading via media-libs/simage library
+media-libs/devil:allegro - Add support for Allegro
+media-libs/devil:nvtt - Add support for media-gfx/nvidia-texture-tools
+media-libs/elementary:quicklaunch - Enable quick-launch support
+media-libs/esdl:image - Enable image support
+media-libs/faad2:digitalradio - Digital Radio Mondiale (warning: disables other decoders)
+media-libs/flickcurl:raptor - Use media-libs/raptor for proper RDF serializing
+media-libs/fontconfig-infinality:nyx - Additional style using croscorefonts
+media-libs/freetype:adobe-cff - Use Adobe CFF as default font-renderer
+media-libs/freetype:bindist - Disable ClearType support (see http://freetype.org/patents.html)
+media-libs/freetype:bzip2 - Support bzip2 compressed PCF fonts.
+media-libs/freetype:cleartype_hinting - New bytecode hinting mode for TrueType fonts that activates subpixel hinting (a.k.a. ClearType hinting) by default
+media-libs/freetype:fontforge - Install internal headers required for TrueType debugger in media-gfx/fontforge (built with USE=truetype-debugger)
+media-libs/freetype:harfbuzz - Use media-libs/harfbuzz for auto-hinting OpenType fonts. WARNING: may trigger circular dependencies!
+media-libs/freetype:infinality - Enable infinality options for improved LCD filtering
+media-libs/freetype:utils - Install utilities and examples from ft2demos
+media-libs/freeverb3:audacious - Build Audacious plugin
+media-libs/freeverb3:forcefpu - Disable assembly code
+media-libs/freeverb3:plugdouble - Build plugins in double precision mode (default is float)
+media-libs/ganv:fdgl - Use experimental force-directed graph layout
+media-libs/gd:webp - Enable support for the webp format
+media-libs/gegl:lensfun - Enable support for media-libs/lensfun.
+media-libs/gegl:umfpack - Enable sparse solving via sci-libs/umfpack.
+media-libs/gegl:webp - Enable support for media-libs/libwebp
+media-libs/giflib:rle - Build converters for RLE format (utah raster toolkit)
+media-libs/gmtk:dconf - Enable support for gnome-base/dconf
+media-libs/grilo:network - Enable network access for media discovery using net-libs/libsoup
+media-libs/grilo:playlist - Enable support for playlists through dev-libs/totem-pl-parser
+media-libs/gst-plugins-bad:bzip2 - Enable bzip2 encoder/decoder plugin
+media-libs/gst-plugins-bad:egl - Enable EGL support
+media-libs/gst-plugins-bad:gles2 - Enable GLES2 support
+media-libs/gst-plugins-base:ivorbis - Enable integer based vorbis decoder
+media-libs/gst-plugins-base:pango - Enable pango GStreamer plugin
+media-libs/gstreamer:orc - Disable some PaX memory protections to allow plugins that use dev-lang/orc for runtime optimization to be used on hardened PaX systems
+media-libs/gstreamer:unwind - Enable sys-libs/libunwind usage for better backtrace support in leaks tracer module
+media-libs/harfbuzz:glib - Compile with GLib Unicode support
+media-libs/harfbuzz:graphite - Use graphite to render complex non-Roman writing systems
+media-libs/jbig2enc:webp - Add support for WEBP image format
+media-libs/leptonica:utils - Install command-line utilities
+media-libs/leptonica:webp - Adds support for the WebP image format
+media-libs/libafterimage:shaping - Use MIT shaped X windows extention.
+media-libs/libafterimage:shm - Use MIT shared memory extention for X image transfer.
+media-libs/libass:harfbuzz - Enables OpenType shaping via media-libs/harfbuzz.
+media-libs/libbdplus:aacs - Add support for decryption of AACS
+media-libs/libbluray:aacs - Add support for decryption of AACS
+media-libs/libbluray:bdplus - Use media-libs/libbdplus for BD+ decryption
+media-libs/libbluray:java - Add support for BD-J
+media-libs/libbluray:udf - Add UDF (Universal Disk Format) support
+media-libs/libbluray:utils - Install command-line utilities and examples
+media-libs/libcanberra:alsa - Enables ALSA sound driver.
+media-libs/libcanberra:gstreamer - Enables gstreamer sound driver. Not useful when alsa or pulseaudio is available.
+media-libs/libcanberra:gtk - Enables building of gtk+ helper library, gtk+ runtime sound effects and the canberra-gtk-play utility. To enable the gtk+ sound effects add canberra-gtk-module to the colon separated list of modules in the GTK_MODULES environment variable.
+media-libs/libcanberra:gtk3 - Enables building of gtk+3 helper library, gtk+3 runtime sound effects and the canberra-gtk-play utility. To enable the gtk+3 sound effects add canberra-gtk-module to the colon separated list of modules in the GTK_MODULES environment variable.
+media-libs/libcanberra:pulseaudio - Enables PulseAudio sound driver that should be able to support positional event sounds. This is the preferred choice for best sound events experience and picked by default if compiled in and possible to use at runtime.
+media-libs/libcanberra:sound - Install x11-themes/sound-theme-freedesktop to get sounds on Gnome and Xfce.
+media-libs/libcanberra:tdb - Enables Trivial Database support for caching purposes.
+media-libs/libextractor:apparmor - Enable apparmor support using sys-libs/libapparmor
+media-libs/libextractor:archive - Enable archive support using app-arch/libarchive
+media-libs/libextractor:gsf - Enable OLE2 (MS Office) plug-in support using gnome-extra/libgsf
+media-libs/libextractor:magic - Enable magic support using sys-apps/file
+media-libs/libextractor:midi - Enable MIDI support through media-libs/libsmf
+media-libs/libffado:test-programs - Install standalone test programs
+media-libs/libggi:vis - Enables sparc vis support for libggi
+media-libs/libgphoto2:serial - Enable serial port support
+media-libs/libgpod:gtk - Enable ArtworkDB support
+media-libs/libgroove:chromaprint - Enable audio fingerprinting using media-libs/chromaprint.
+media-libs/libgroove:loudness - Enable loudness detection according to the EBU R128 standard using media-libs/libebur128.
+media-libs/libgroove:sound - Enable audio playing.
+media-libs/liblastfm:fingerprint - Build the lastfm-fingerprint library
+media-libs/libmp4v2:utils - Install command-line utilities
+media-libs/libmypaint:gegl - Add support for media-libs/gegl
+media-libs/libomxil-bellagio:audioeffects - enable audio volume/mixer effects components
+media-libs/libomxil-bellagio:clocksrc - enable clock component
+media-libs/libomxil-bellagio:videoscheduler - enable xvideosink video scheduler
+media-libs/libopenglrecorder:openh264 - Enable H.264 support using media-libs/openh264
+media-libs/libopenglrecorder:vpx - Enable VP8/VP9 codec support via media-libs/libvpx
+media-libs/libpagemaker:tools - Build command line file format conversion tools
+media-libs/libpng:apng - support unofficial APNG (Animated PNG) spec
+media-libs/libpostproc:pic - Force shared libraries to be built as PIC (this is slower).
+media-libs/libquicktime:schroedinger - Enable Dirac video support (an advanced royalty-free video compression format) via libschroedinger (high-speed implementation in C of the Dirac codec)
+media-libs/libraw:demosaic - Enable support for external interpolation algorithms
+media-libs/libsdl:joystick - Control joystick support (disable at your own risk)
+media-libs/libsdl:sound - Control audio support (disable at your own risk)
+media-libs/libsdl:tslib - Build with tslib support for touchscreen devices
+media-libs/libsdl:video - Control video support (disable at your own risk)
+media-libs/libsdl2:fusionsound - use FusionSound audio driver
+media-libs/libsdl2:gles - include OpenGL ES support
+media-libs/libsdl2:haptic - Enable the haptic (force feedback) subsystem
+media-libs/libsdl2:joystick - Control joystick support (disable at your own risk)
+media-libs/libsdl2:sound - Control audio support (disable at your own risk)
+media-libs/libsdl2:tslib - Build with tslib support for touchscreen devices
+media-libs/libsdl2:video - Control video support (disable at your own risk)
+media-libs/libvisio:tools - Build conversion tools
+media-libs/libvpx:highbitdepth - Enable 10 and 12 bit support for VP9.
+media-libs/libvpx:postproc - Enable additional post processing filters
+media-libs/libvpx:svc - Enable spatial-svc support (experimental)
+media-libs/libwebp:experimental - Build with -DWEBP_EXPERIMENTAL_FEATURES
+media-libs/libwebp:swap-16bit-csp - Enable byte swapping for 16 bit colorspace
+media-libs/libyami:dmabuf - Enable dma_buf buffer sharing.
+media-libs/libyami:egl - Enable EGL support.
+media-libs/libyami:md5 - Add support for generating md5 sums for each frame.
+media-libs/libyami:v4l - Add support for V4L2 hardware codecs.
+media-libs/libzmf:tools - Build conversion tools
+media-libs/lilv:dyn-manifest - Add LV2 Dynamic Manifest support. See http://lv2plug.in/ns/ext/dynmanifest/
+media-libs/lv2:plugins - Enables examples plugins.
+media-libs/lvtk:gtk2 - Enable x11-libs/gtk+:2 based GUI support
+media-libs/lvtk:tools - Compile and install ttl2c tool
+media-libs/mediastreamer:amr - Use of AMR Narrow Band codec plugin
+media-libs/mediastreamer:filters - Enable compilation of filters
+media-libs/mediastreamer:g726 - Support g726 codec
+media-libs/mediastreamer:g729 - Use g726 codec plugin
+media-libs/mediastreamer:ilbc - Use of iLBC (RFC3951) codec plugin
+media-libs/mediastreamer:ntp-timestamp - Turn on NTP timestamping on received packet
+media-libs/mediastreamer:opus - Enable opus codec support
+media-libs/mediastreamer:ortp - Enable usage of net-libs/ortp
+media-libs/mediastreamer:pcap - Enable usage of net-libs/libpcap
+media-libs/mediastreamer:silk - Use silk (skype protocol) codec plugin
+media-libs/mediastreamer:video - Enable video support
+media-libs/mesa:bindist - Disable patent-encumbered ARB_texture_float, EXT_texture_shared_exponent, and EXT_packed_float extensions.
+media-libs/mesa:classic - Build drivers based on the classic architecture.
+media-libs/mesa:d3d9 - Enable Direct 3D9 API through Nine state tracker. Can be used together with patched wine.
+media-libs/mesa:dri3 - Enable DRI3 support.
+media-libs/mesa:egl - Enable EGL support.
+media-libs/mesa:gallium - Build drivers based on Gallium3D, the new architecture for 3D graphics drivers.
+media-libs/mesa:gbm - Enable the Graphics Buffer Manager for EGL on KMS.
+media-libs/mesa:gles1 - Enable GLESv1 support.
+media-libs/mesa:gles2 - Enable GLESv2 support.
+media-libs/mesa:llvm - Enable LLVM backend for Gallium3D.
+media-libs/mesa:opencl - Enable the Clover Gallium OpenCL state tracker.
+media-libs/mesa:openmax - Enable OpenMAX video decode/encode acceleration for Gallium3D.
+media-libs/mesa:osmesa - Build the Mesa library for off-screen rendering.
+media-libs/mesa:pax_kernel - Enable if the user plans to run the package under a pax enabled hardened kernel
+media-libs/mesa:pic - disable optimized assembly code that is not PIC friendly
+media-libs/mesa:unwind - Add support for stack trace unwinding and function name resolution
+media-libs/mesa:valgrind - Compile in valgrind memory hints
+media-libs/mesa:vdpau - Enable the VDPAU acceleration interface for the Gallium3D Video Layer.
+media-libs/mesa:vulkan - Enable Vulkan drivers
+media-libs/mesa:wayland - Enable support for dev-libs/wayland
+media-libs/mesa:xa - Enable the XA (X Acceleration) API for Gallium3D.
+media-libs/mesa:xvmc - Enable the XvMC acceleration interface for the Gallium3D Video Layer.
+media-libs/mlt:compressed-lumas - Compress the luma files in png.
+media-libs/mlt:frei0r - Build the module for media-plugins/frei0r-plugins
+media-libs/mlt:kdenlive - Build support for kde-apps/kdenlive
+media-libs/mlt:lua - Build SWIG bindings for Lua
+media-libs/mlt:melt - Build the melt commandline tool
+media-libs/mlt:opencv - Build motion tracking module using media-libs/opencv
+media-libs/mlt:python - Build SWIG bindings for Python
+media-libs/mlt:rtaudio - Builds rtaudio consumer for native audio support on multiple platforms.
+media-libs/mlt:ruby - Build SWIG bindings for Ruby
+media-libs/mlt:sdl2 - Build media-libs/libsdl2 module
+media-libs/netpbm:rle - Build converters for the RLE format (utah raster toolkit)
+media-libs/opencolorio:pdf - Install extra documentation in PDF format
+media-libs/opencv:contrib - Install user contributed scripts from opencv_contrib (Experimental!)
+media-libs/opencv:contrib_cvv - CVV module requires Qt5
+media-libs/opencv:contrib_dnn - DNN module contrib requires tiny dnn
+media-libs/opencv:contrib_hdf - HDF module requires sci-libs/hdf5
+media-libs/opencv:contrib_sfm - SFM module requires eigen, gflags, and glog
+media-libs/opencv:contrib_xfeatures2d - Enables xfeatures2d and autodownload of samples in contrib
+media-libs/opencv:cuda - Enable NVIDIA Cuda computations support (Experimental!)
+media-libs/opencv:eigen - Enable usage of dev-cpp/eigen for computations
+media-libs/opencv:gdal - Enable support for sci-libs/gdal library
+media-libs/opencv:gflags - Use Google's C++ argument parsing library
+media-libs/opencv:glog - Use Google's C++ loggin library
+media-libs/opencv:ipp - Enable Intel Integrated Primitive support
+media-libs/opencv:opencl - Add support for OpenCL
+media-libs/opencv:tesseract - Use Google's OCR Engine
+media-libs/opencv:testprograms - Build and install programs for testing OpenCV (performance)
+media-libs/opencv:vtk - Build new 3D visualization module viz based on sci-libs/vtk
+media-libs/opencv:webp - Enable support for webp image format
+media-libs/openh264:plugin - Install the Gecko Media Plugin (GMP) for use with Mozilla packages
+media-libs/openh264:utils - Install the CLI encoder and decoder utilities
+media-libs/openimageio:colorio - Use media-libs/opencolorio
+media-libs/openimageio:cpu_flags_x86_avx512f - SIMD Optimization
+media-libs/openimageio:cpu_flags_x86_f16c - SIMD Optimization
+media-libs/openimageio:field3d - Use media-libs/Field3D
+media-libs/openimageio:opencv - Use media-libs/opencv
+media-libs/openimageio:ptex - Use media-libs/ptex
+media-libs/opensubdiv:cuda - Enable NVIDIA CUDA Toolkit support through dev-util/nvidia-cuda-toolkit.
+media-libs/opensubdiv:opencl - Enable OpenCL support through virtual/opencl.
+media-libs/opensubdiv:ptex - Adds support for faster per-face texture mapping through media-libs/ptex.
+media-libs/opensubdiv:tbb - Enable multithreading with the Intel Threads Building Blocks through dev-cpp/tbb.
+media-libs/opus:ambisonics - Enable ambisonics support (experimental).
+media-libs/opus:custom-modes - Build with custom-modes.
+media-libs/opusfile:fixed-point - Enable fixed-point arithmetic operations
+media-libs/opusfile:float - Enable floating point arithmetic operations
+media-libs/opusfile:http - Enable http connections
+media-libs/osl:cpu_flags_x86_avx512f - SIMD Optimization
+media-libs/osl:cpu_flags_x86_f16c - SIMD Optimization
+media-libs/osl:partio - Use media-libs/partio
+media-libs/phonon:designer - Install plugin for dev-qt/designer
+media-libs/phonon:vlc - Install VLC Phonon backend
+media-libs/phonon-gstreamer:network - Enable network streaming support via libsoup
+media-libs/portmidi:test-programs - Install various example programs
+media-libs/qtav:gui - Build a video player gui
+media-libs/quvi:json - Enable support for JSON output
+media-libs/raptor:json - Enable support for JSON parsing
+media-libs/raspberrypi-userland-bin:hardfp - Use armv6 hardfp ABI
+media-libs/sdif:ftruncate - Enables usage of ftruncate v. truncate
+media-libs/sdl-image:webp - support loading WEBP images
+media-libs/sdl-mixer:fluidsynth - Use media-sound/fluidsynth for MIDI support
+media-libs/sdl-mixer:midi - basic support for MIDI files
+media-libs/sdl-mixer:mod - basic support for MOD files
+media-libs/sdl-mixer:playtools - Install playwave and playmus tools (useful for testing)
+media-libs/sdl-mixer:smpeg - Use media-libs/smpeg for MP3 support
+media-libs/sdl-mixer:wav - support WAVE files
+media-libs/sdl-sound:physfs - Enable physfs support
+media-libs/sdl2-image:webp - support loading WEBP images
+media-libs/sdl2-mixer:fluidsynth - Use media-sound/fluidsynth for MIDI support
+media-libs/sdl2-mixer:midi - basic support for MIDI files
+media-libs/sdl2-mixer:mod - basic support for MOD files
+media-libs/sdl2-mixer:playtools - Install playwave and playmus tools (useful for testing)
+media-libs/sdl2-mixer:smpeg - Use media-libs/smpeg for MP3 support
+media-libs/sdl2-mixer:tremor - enable OGG Vorbis music via libtremor
+media-libs/sdl2-mixer:wav - support WAVE files
+media-libs/sge:image - enable sdl-image support
+media-libs/spandsp:fixed-point - Enable fixed point support
+media-libs/speex:utils - Enables speex commandline utilities (speexenc, speexdec).
+media-libs/speex:vbr - Enable VBR support.
+media-libs/svgalib:kernel-helper - Build the helper kernel module
+media-libs/taglib:boost - Use dev-libs/boost instead of GCC built-ins
+media-libs/tremor:low-accuracy - enable 32bit only multiply operations
+media-libs/vigra:valgrind - Enable valgrind in make check
+media-libs/waffle:egl - Enable EGL support
+media-libs/waffle:gbm - Enable support for the Generic Buffer Manager (gbm)
+media-libs/waffle:wayland - Enable Wayland support
+media-libs/x264:10bit - Set output bit depth to 10, this may not be compatible with all decoders
+media-libs/x264:interlaced - enable interlaced encoding support, this can decrease encoding speed by up to 2%
+media-libs/x264:opencl - Add support for OpenCL.
+media-libs/x264:pic - disable optimized assembly code that is not PIC friendly
+media-libs/x265:10bit - Add support for producing 10bits HEVC.
+media-libs/x265:12bit - Add support for producing 12bits HEVC.
+media-libs/x265:numa - Build with support for NUMA nodes.
+media-libs/x265:pic - Disable optimized assembly code that is not PIC friendly
+media-libs/x265:power8 - Enable support for Power 8 assembly optimizations.
+media-libs/xine-lib:bluray - Enable playback of Blu-ray filesystems using media-libs/libbluray
+media-libs/xine-lib:dxr3 - Enable support for DXR3 mpeg acceleration cards.
+media-libs/xine-lib:flac - Build the media-libs/flac based FLAC demuxer and decoder. This flag is not needed for playing FLAC content, neither standalone nor in Ogg container (OggFLAC), but might have better support for exotic features like 24-bit samples or 96kHz sample rates.
+media-libs/xine-lib:fusionsound - Enable support for the Fusion audio sub system
+media-libs/xine-lib:gtk - Build the gdkpixbuf-based image decoder plugin.
+media-libs/xine-lib:imagemagick - Build the ImageMagick-based image decoder plugin.
+media-libs/xine-lib:mad - Build the media-libs/libmad based mp3 decoder. This mp3 decoder has superior support compared to the one coming from FFmpeg that is used as a fallback. If you experience any bad behaviour with mp3 files (skipping, distorted sound) make sure you enabled this USE flag.
+media-libs/xine-lib:mmap - Use mmap() function while reading file from local disks. Using mmap() will use more virtual memory space, but leaves to the Kernel the task of caching the file's data. mmap() access should be faster, but might misbehave if the device where the file resides in is removed during playback.
+media-libs/xine-lib:truetype - Use media-libs/freetype for font rendering and media-libs/fontconfig for font discovery. Enabling this USE flag will allow OSD (such as subtitles) to use more advanced font and to more easily select which font to use. The support for TrueType fonts in xine-lib is still experimental, and might not be as good looking as the bitmap fonts used with this USE flag disabled.
+media-libs/xine-lib:vdr - Build the VDR plugin
+media-libs/xine-lib:vidix - Enable support for vidix video output.
+media-libs/xine-lib:vis - Adds support for SIMD optimizations for UltraSPARC processors.
+media-libs/xine-lib:vpx - Enable VP8 codec support via media-libs/libvpx.
+media-libs/xine-lib:xvmc - Enable support for XVideo Motion Compensation (accelerated mpeg playback).
+media-libs/xvid:pic - disable optimized assembly code that is not PIC friendly
+media-plugins/alsa-plugins:arcam_av - Enables Arcam AV control plugin
+media-plugins/alsa-plugins:mix - Enables upmix and vdownmix plugin
+media-plugins/alsa-plugins:usb_stream - Enables usb_stream plugin
+media-plugins/audacious-plugins:adplug - Build with AdPlug (Adlib sound card emulation) support
+media-plugins/audacious-plugins:ampache - Support controlling audacious via www-apps/ampache
+media-plugins/audacious-plugins:aosd - Enable support for Audacious OSD
+media-plugins/audacious-plugins:bs2b - Enable Bauer Bauer stereophonic-to-binaural headphone filter
+media-plugins/audacious-plugins:cue - Support CUE sheets using the libcue library
+media-plugins/audacious-plugins:fluidsynth - Support FluidSynth as MIDI synth backend
+media-plugins/audacious-plugins:gme - Support various gaming console music formats
+media-plugins/audacious-plugins:gtk3 - Link against version 3 of the GIMP Toolkit instead of version 2 (x11-libs/gtk+)
+media-plugins/audacious-plugins:hotkeys - Enable support for controlling via hotkeys
+media-plugins/audacious-plugins:http - Support HTTP streams through neon
+media-plugins/audacious-plugins:scrobbler - Build with scrobbler/LastFM submission support
+media-plugins/audacious-plugins:sid - Build with SID (Commodore 64 Audio) support
+media-plugins/audacious-plugins:soxr - Build with SoX Resampler support
+media-plugins/audacious-plugins:speedpitch - Enable speed/pitch effects
+media-plugins/calf:experimental - Enable experimental features/plugins
+media-plugins/calf:lv2 - Add support for Ladspa V2
+media-plugins/frei0r-plugins:facedetect - Enables building of facedetect plugin, which depends on media-libs/opencv
+media-plugins/frei0r-plugins:scale0tilt - Enables building of scale0tilt and vectorscope plugins, which depend on media-libs/gavl
+media-plugins/gkrellmpc:threads - Use separate thread to init connection (unsafe)
+media-plugins/grilo-plugins:chromaprint - Enable Chromaprint support
+media-plugins/grilo-plugins:daap - Enable dmap support through net-libs/libdmapsharing
+media-plugins/grilo-plugins:flickr - Enable Flickr support
+media-plugins/grilo-plugins:freebox - Build support for viewing TV channels using Freebox
+media-plugins/grilo-plugins:gnome-online-accounts - Enable net-libs/gnome-online-accounts support
+media-plugins/grilo-plugins:subtitles - Enables support for subtitle from OpenSubtitles
+media-plugins/grilo-plugins:thetvdb - Build support for thetvdb.com
+media-plugins/grilo-plugins:tracker - Build support for content discovery using the app-misc/tracker indexer
+media-plugins/grilo-plugins:vimeo - Build support for Vimeo content discovery using net-libs/libsoup and dev-libs/libgcrypt
+media-plugins/grilo-plugins:youtube - Build support for YouTube content discovery using dev-libs/libgdata
+media-plugins/gst-plugins-gl:libvisual - Enable visualization effects via media-libs/libvisual
+media-plugins/gst-plugins-meta:http - Enable http streaming via net-libs/libsoup
+media-plugins/gst-plugins-meta:libvisual - Enable visualization effects via media-libs/libvisual
+media-plugins/gst-plugins-meta:opus - Enable Opus audio codec support
+media-plugins/gst-plugins-meta:vpx - Enables vp8 codec support using libvpx, required to play some HTML5 videos
+media-plugins/gst-plugins-vaapi:drm - Enable DRM renderer
+media-plugins/gst-plugins-vaapi:egl - Enable EGL support
+media-plugins/hexter:gtk2 - Enable x11-libs/gtk+:2 based GUI
+media-plugins/imlib2_loaders:eet - Enable Eet image loader
+media-plugins/imlib2_loaders:xcf - Enable XCF image loader
+media-plugins/kipi-plugins:flashexport - Build the flash export plugin
+media-plugins/kipi-plugins:mediawiki - Build the mediawiki export plugin
+media-plugins/kipi-plugins:remotestorage - Build plugin for remote storage using network protocols such as FTP, SSH, SAMBA via kde-frameworks/kio
+media-plugins/kipi-plugins:vkontakte - Build plugin for vkontakte.ru
+media-plugins/mediastreamer-ilbc:20ms-frames - enable 20ms frame size (default is 30ms). Some VOIP providers such as Gizmo5 (aka Sipphone) require the codec to be compiled with the 30ms setting.
+media-plugins/mythplugins:cdr - Allows MythMusic to burn CD-Rs
+media-plugins/mythplugins:exif - Allows MythGallery to read EXIF data from photos
+media-plugins/mythplugins:fftw - Adds visual effects to MythMusic when playing back music
+media-plugins/mythplugins:hls - HTTP Live Streaming support
+media-plugins/mythplugins:mytharchive - Allows you to archive recorded content to CD or DVD
+media-plugins/mythplugins:mythbrowser - Adds a web browser within MythTV
+media-plugins/mythplugins:mythgallery - Adds a picture viewing gallery within MythTV
+media-plugins/mythplugins:mythgame - Adds a frontend to various ROM emulators within MythTV
+media-plugins/mythplugins:mythmusic - Adds the ability for MythTV to act as a music player
+media-plugins/mythplugins:mythnetvision - Adds the ability to view netvision devices within MythTV
+media-plugins/mythplugins:mythnews - Adds a news viewer within MythTV
+media-plugins/mythplugins:mythweather - Adds weather information within MythTV
+media-plugins/mythplugins:mythzoneminder - Adds support for zoneminder (requires a server with the appropriate mythtv daemon somewhere on the network).
+media-plugins/mythplugins:raw - Allows MythGallery to view photos saved in RAW format
+media-plugins/vdr-burn:dvdarchive - DMH DVD - Archive
+media-plugins/vdr-epgsearch:conflictcheckonly - ToDo
+media-plugins/vdr-epgsearch:epgsearchonly - ToDo
+media-plugins/vdr-epgsearch:quicksearch - ToDo
+media-plugins/vdr-epgsearch:tre - Add support for unlimited fuzzy searching with help of dev-libs/tre library
+media-plugins/vdr-graphtft:graphtft-fe - Install external x11 remote frontend
+media-plugins/vdr-graphtft:theme_avp - graphTFT Alien vs. Predato theme
+media-plugins/vdr-graphtft:theme_deepblue - graphTFT default theme
+media-plugins/vdr-graphtft:theme_deeppurple - graphTFT Deep Purple theme
+media-plugins/vdr-graphtft:theme_poetter - graphTFT Poetter theme
+media-plugins/vdr-graphtft:touchscreen - Enable Touchscreen support
+media-plugins/vdr-music:graphtft - Enable support for media-plugins/vdr-graphtft
+media-plugins/vdr-pvr350:yaepg - Enables full support for the output format of vdr-yaepg
+media-plugins/vdr-streamdev:client - Compile the VDR plugin vdr-streamdev-client that acts like a dvb-budget card
+media-plugins/vdr-streamdev:server - Compile the VDR plugin vdr-streamdev-server that allows remote systems to access the DVB cards used for the local VDR
+media-plugins/vdr-text2skin:contrib - Install user contributed scripts
+media-plugins/vdr-vdrmanager:stream - Add support for streaming Video to Android client
+media-plugins/vdr-weatherng:dxr3 - enables lower osd color depth for dxr3 cards
+media-plugins/vdr-xine:yaepg - Enables support for the plugin vdr-yaepg (showing scaled video besides OSD)
+media-plugins/vdr-xineliboutput:bluray - Enable BluRay metadata support through media-libs/libbluray
+media-plugins/vdr-xineliboutput:cec - Enable CEC support through dev-libs/libcec
+media-plugins/vdr-xineliboutput:libextractor - Use media-libs/libextractor to gather files' metadata in media-player
+media-plugins/vdr-xineliboutput:vdr - Compile the vdr output plugin to use local or remote xine as output
+media-plugins/vdr-xineliboutput:xine - Compile the xine input plugin for displaying vdr video and OSD
+media-radio/ax25-tools:X - Enable some X based configuration tools.
+media-radio/fldigi:hamlib - Enables support by the Hamlib amateur radio rig control library to get/set frequency and mode of the ham radio in use
+media-radio/tucnak:hamlib - Enables support by the Hamlib amateur radio rig control library to get/set frequency and mode of the ham radio
+media-radio/unixcw:ncurses - Enables building the curses based morse code tutor program 'cwcp'.
+media-radio/xastir:festival - Enable text to speech synthesizer
+media-radio/xastir:gdal - Support for some further map formats
+media-radio/xastir:geotiff - Install geotiff support. Allows using USGS DRG topo maps or other types of geotiff mapes/images
+media-sound/abcde:id3tag - Support ID3, ID3v2 tagging of audio files
+media-sound/abcde:mac - Enable support for Monkey's Audio files
+media-sound/abcde:normalize - Add support for normalizing audio file volume levels
+media-sound/abcde:opus - Support opus encoding using opusenc
+media-sound/abcde:replaygain - Support for Replay Gain metadata, for relative volume adjustment
+media-sound/abcm2ps:pango - Use the pango library to render fonts with non-latin characters
+media-sound/alsa-utils:bat - install basic audio tester (BAT) util
+media-sound/alsa-utils:libsamplerate - install utils that use libsamplerate (e.g. alsaloop)
+media-sound/alsa-utils:ncurses - install utils that use ncurses (e.g. alsamixer)
+media-sound/alsaplayer:id3tag - Enables ID3 tagging with id3tag library
+media-sound/amsynth:dssi - Enable support for DSSI Soft Synth Interface
+media-sound/aqualung:ifp - Enable support for iRiver iFP portable audio players
+media-sound/aqualung:lua - Enable support for programmable title formatting with dev-lang/lua
+media-sound/aqualung:mac - Enable support for decoding Monkey's Audio files
+media-sound/aqualung:podcast - Enable podcast support
+media-sound/aqualung:systray - Enable system tray support
+media-sound/ardour:lv2 - Add support for Ladspa V2
+media-sound/ario:audioscrobbler - Enable song tracking via last.fm
+media-sound/ario:idle - Enable experimental support for MPD's idle command to reduce bandwidth and cpu usage, requires MPD 0.14
+media-sound/asunder:mac - Support for creation of Monkey's Audio files (APE)
+media-sound/asunder:opus - Support for creation of Opus files
+media-sound/audacious:gtk3 - Link against version 3 of the GIMP Toolkit instead of version 2 (x11-libs/gtk+)
+media-sound/audacity:id3tag - Enables ID3 tagging with id3tag library
+media-sound/audacity:lv2 - Add support for Ladspa V2
+media-sound/audacity:midi - Enables MIDI support
+media-sound/audacity:portmixer - Enable the internal portmixer feature
+media-sound/audacity:sbsms - Enables sbsms library support for slower, more accurate pitch and tempo changing
+media-sound/audacity:soundtouch - Enables soundtouch library support for pitch and tempo changing
+media-sound/audacity:twolame - Enables twolame support (MPEG Audio Layer 2 encoder)
+media-sound/audacity:vamp - Enables vamp plugins support (Audio analysing plugins)
+media-sound/audacity:vst - Enable VST plugin support
+media-sound/beets:badfiles - Validate MP3 & FLAC files
+media-sound/beets:bpd - Enable support for media-sound/mpd server emulation
+media-sound/beets:chroma - Enable support for acoustic fingerprinting plugin using media-libs/chromaprint
+media-sound/beets:convert - Enable support for the convert plugin which makes it possible to transcode files
+media-sound/beets:discogs - Enable support for the discogs API plugin
+media-sound/beets:lastgenre - Enable support for importing music genres from last.fm tags
+media-sound/beets:lastimport - Enable support for importing your last.fm playcounts
+media-sound/beets:mpdstats - Enable support for collecting statistic about listening habits from media-sound/mpd
+media-sound/beets:opus - Enable opus support in gstreamer-based replaygain
+media-sound/beets:replaygain - Enable support for Replay Gain metadata calculation during import
+media-sound/beets:thumbnails - Generate thumbnails for albums
+media-sound/beets:web - Enable embedded webserver support through dev-python/flask
+media-sound/bluez-alsa:hcitop - Enable top-like monitoring tool for HCI
+media-sound/cantata:cdio - Use dev-libs/libcdio-paranoia for CD support (instead of cdparanoia)
+media-sound/cantata:http-server - Enable internal HTTP server to play non-MPD files
+media-sound/cantata:replaygain - Enable ReplayGain support, for relative volume adjustments
+media-sound/cantata:streaming - Enable playback of MPD HTTP streams using LibVLC (media-video/vlc)
+media-sound/clementine:box - Enable filesharing via Box.com
+media-sound/clementine:dropbox - Enable Dropbox support
+media-sound/clementine:googledrive - Enable Google Drive support
+media-sound/clementine:lastfm - Use liblastfm for fetching song info, scrobbling and radio streams
+media-sound/clementine:moodbar - Enable moodbar support
+media-sound/clementine:projectm - Build with ProjectM visualization
+media-sound/clementine:seafile - Enable support for seafile: a file sync service
+media-sound/clementine:skydrive - Enable Skydrive support
+media-sound/clementine:wiimote - Enable support for Wii remote
+media-sound/cmus:cdio - use libcdio for CD support
+media-sound/cmus:cue - enable CUE sheet parsing
+media-sound/cmus:discid - enable reading the ID of the inserted CD
+media-sound/cmus:opus - enable support for media-libs/opusfile
+media-sound/cmus:pidgin - install support script for net-im/pidgin
+media-sound/cmus:tremor - use libivorbis from media-libs/tremor instead of media-libs/libvorbis
+media-sound/csound:beats - Build the beats score frontend
+media-sound/csound:chua - Build the chua opcodes
+media-sound/csound:csoundac - Build the CsoundAC extension module
+media-sound/csound:double-precision - Use double-precision floating point for audio samples
+media-sound/csound:dssi - Build the DSSI opcodes
+media-sound/csound:fluidsynth - Build the fluidsynth opcodes
+media-sound/csound:image - Build the image opcodes
+media-sound/csound:keyboard - Build Virtual MIDI keyboard
+media-sound/csound:linear - Build the linear algebra Opcodes
+media-sound/csound:luajit - Use the lua just-in-time compiler dev-lang/luajit instead of dev-lang/lua
+media-sound/csound:portmidi - Build the PortMIDI I/O module
+media-sound/csound:samples - Install the HRTF datafiles for use with hrtfmove, hrtfmove2, hrtfstat, hrtfearly, and hrtfreverb
+media-sound/csound:score - Build the alternative score parser
+media-sound/csound:stk - Build the stk opcodes
+media-sound/csound:tcl - Build the tcl interface and clients
+media-sound/csound:utils - Build stand-alone executables for utilities that can also be used via `csound -U`
+media-sound/csound:websocket - Build the websocket opcode
+media-sound/darkice:aacplus - AAC+ encoding via media-libs/libaacplus
+media-sound/darkice:opus - Enable Opus audio codec support
+media-sound/darkice:twolame - Build with twolame support
+media-sound/deinvert:liquid - improve sound quality using net-libs/liquid-dsp
+media-sound/deinvert:wav - wav file support using media-libs/libsndfile
+media-sound/denemo:fluidsynth - Enable Fluidsynth MIDI software synthesis
+media-sound/denemo:portmidi - Enable support for the portmidi backend
+media-sound/dir2ogg:mac - Add support for decoding Monkey's Audio files
+media-sound/dir2ogg:wma - Add support for wma files through mplayer
+media-sound/drumstick:fluidsynth - Enable support for media-sound/fluidsynth
+media-sound/easytag:opus - Enable support for media-libs/opus and media-libs/opusfile (opus audio codec)
+media-sound/ecasound:lv2 - Add support for Ladspa V2
+media-sound/ecasound:oil - Use dev-libs/liboil for inner loop optimizations
+media-sound/fapg:xspf - Enable support for saving XSPF playlists.
+media-sound/forked-daapd:itunes - Enable support for iTunes library XML
+media-sound/forked-daapd:lastfm - Enable LastFM scrobbling support
+media-sound/forked-daapd:mpd - Enable streaming to mpd
+media-sound/gimmix:cover - Enable cover art fetching
+media-sound/gimmix:lyrics - Enable lyric fetching
+media-sound/gmpc:unique - Enable single instance support using dev-libs/libunique
+media-sound/gmpc:xspf - Enable support for reading and saving XSPF playlists
+media-sound/gmusicbrowser:extras - Install some extra deps for plugins (ex. Titlebar)
+media-sound/gogglesmm:opus - Enable support for opus codec
+media-sound/herrie:http - Enable http streaming
+media-sound/herrie:xspf - Enable support for reading and saving XSPF playlists
+media-sound/hydrogen:archive - Use libarchive instead of libtar
+media-sound/hydrogen:portmidi - Add portmidi support
+media-sound/jack-audio-connection-kit:coreaudio - Build the CoreAudio driver on Mac OS X systems
+media-sound/jack-audio-connection-kit:cpudetection - Enables runtime cpudetection
+media-sound/jack-audio-connection-kit:pam - Add basic realtime configuration via sys-auth/realtime-base
+media-sound/jack2:celt - Support CELT low delay audio codec (media-libs/celt)
+media-sound/jack2:classic - Enable building of jackd
+media-sound/jack2:opus - Support media-libs/opus
+media-sound/jack2:pam - Add basic realtime configuration via sys-auth/realtime-base
+media-sound/jalv:gtk2 - Adds support for GTK+2 in addition to GTK+3 controlled by the gtk useflag.
+media-sound/jalv:gtkmm - Adds support for dev-cpp/gtkmm: C++ interface for GTK+2
+media-sound/kid3:acoustid - Enable support for acoustic fingerprinting plugin using (media-libs/chromaprint)
+media-sound/klick:rubberband - Enable rubberband support
+media-sound/lame:frontend - Build and install the 'lame' executable frontend to lame libraries.
+media-sound/lame:mp3rtp - Build the mp3-to-RTP streaming utility. **UNSUPPORTED**
+media-sound/lilypond:guile2 - Enable experimental support for Guile 2
+media-sound/linuxsampler:lv2 - Add support for Ladspa V2
+media-sound/lmms:fluidsynth - Enables Fluidsynth MIDI software synthesis plugin.
+media-sound/lmms:libgig - Enables GIG player plugin.
+media-sound/lmms:soundio - Enalbes libsoundio support.
+media-sound/lmms:stk - Enables STK Mallet plugin.
+media-sound/lmms:vst - Enables the VeSTige plugin to run VST plugins through Wine.
+media-sound/lyvi:mpris - Enable MPRIS support
+media-sound/mangler:espeak - Text to speech engine
+media-sound/mangler:g15 - Logitech g15 lcd support
+media-sound/mangler:opus - Codec specialized for speech over the internet
+media-sound/mixxx:hid - Enable HID controller support
+media-sound/mixxx:shout - Enable broadcasting support via media-libs/libshout
+media-sound/moc:cache - Enable tags caching support
+media-sound/moc:magic - Use libmagic to determine mimetypes
+media-sound/moc:sid - Build with SID (Commodore 64 Audio) support
+media-sound/moc:tremor - Build vorbis support using an integer implementation of the vorbis library (media-libs/tremor)
+media-sound/mp3blaster:sid - Build with SID (Commodore 64 Audio) support
+media-sound/mp3splt-gtk:audacious - Include media-sound/audacious support
+media-sound/mpd:adplug - Enable the AdPlug decoder plugin
+media-sound/mpd:cdio - Use libcdio for ISO9660 parsing support
+media-sound/mpd:curl - Support for web stream listening
+media-sound/mpd:eventfd - Use the eventfd function in MPD's event loop
+media-sound/mpd:faad - Use external faad library for AAC decoding
+media-sound/mpd:fifo - Support writing audio to a FIFO
+media-sound/mpd:fluidsynth - Enables Fluidsynth MIDI software synthesis (discouraged)
+media-sound/mpd:gme - Enables support for media-libs/game-music-emu for playing various video game music formats.
+media-sound/mpd:id3tag - Support for ID3 tags
+media-sound/mpd:inotify - Use the Linux kernel inotify subsystem to notice changes to mpd music library
+media-sound/mpd:lame - Support for MP3 streaming via Icecast2
+media-sound/mpd:libmpdclient - Enable support for remote mpd databases
+media-sound/mpd:libsoxr - Enable the libsoxr resampler
+media-sound/mpd:mpg123 - Enable support for mp3 decoding over media-sound/mpg123
+media-sound/mpd:network - Enables network streaming support
+media-sound/mpd:nfs - Enable support for the Network File System
+media-sound/mpd:opus - Enable Opus codec support
+media-sound/mpd:pipe - Support writing audio to a pipe
+media-sound/mpd:recorder - Enables output plugin for recording radio streams
+media-sound/mpd:sid - Build with SID (Commodore 64 Audio) support
+media-sound/mpd:signalfd - Use the signalfd function in MPD's event loop
+media-sound/mpd:soundcloud - Build plugin to access soundcloud
+media-sound/mpd:systemd - Enable support for systemd socket activation
+media-sound/mpd:twolame - Support twolame MPEG-2 encoding
+media-sound/mpd:webdav - Enable using music from a WebDAV share
+media-sound/mpd:wildmidi - Enable MIDI support via wildmidi
+media-sound/mpd:zip - Support for ZIP files
+media-sound/mpfc:wav - Enable wav audio codec support
+media-sound/mpg123:int-quality - Use rounding instead of fast truncation for integer output, where possible
+media-sound/mumble:g15 - Enable support for the Logitech G15 LCD (and compatible devices).
+media-sound/mumble:speech - Enable text-to-speech support in Mumble.
+media-sound/murmur:ice - Use dev-libs/Ice to enable remote control capabilities.
+media-sound/musescore:portmidi - Enable support for building against media-libs/portmidi
+media-sound/ncmpc:artist-screen - Enable artist screen
+media-sound/ncmpc:chat-screen - Enable the chat screen
+media-sound/ncmpc:colors - Enable color support
+media-sound/ncmpc:help-screen - Enable the help screen
+media-sound/ncmpc:key-screen - Enable key editor screen
+media-sound/ncmpc:lyrics-screen - Enable lyrics screen
+media-sound/ncmpc:mouse - Enable curses getmouse support
+media-sound/ncmpc:search-screen - Enable search screen
+media-sound/ncmpc:song-screen - Enable song viewer screen
+media-sound/ncmpcpp:clock - Enable clock screen
+media-sound/ncmpcpp:outputs - Enable outputs screen
+media-sound/ncmpcpp:visualizer - Enable visualizer screen with sound wave/frequency spectrum modes
+media-sound/patchage:jack-dbus - Use Jack via D-Bus instead of libjack
+media-sound/patchage:session - Include experimental Jack session management (save/restore) support
+media-sound/pithos:appindicator - Enable usage of appindicator to export menu options in to unity
+media-sound/pithos:keybinder - Use keybinder to enable global key bindings
+media-sound/pms:regex - Enable regular expression searches
+media-sound/podcatcher:bittorrent - Enable support for bittorrent downloads
+media-sound/potamus:opus - Adds support for the Opus codec.
+media-sound/pragha:glyr - Enable music metadata searchengine support using media-libs/glyr
+media-sound/pragha:grilo - Play songs on DLNA servers using media-libs/grilo
+media-sound/pragha:keybinder - Enable shortcut support using dev-libs/keybinder
+media-sound/pragha:lastfm - Enable last.fm support using media-libs/libclastfm
+media-sound/pragha:peas - Enable various plugins that will pull in dev-libs/libpeas as a dependency
+media-sound/pragha:playlist - Enable enhanced playlist support using dev-libs/totem-pl-parser
+media-sound/pragha:rygel - Share music on DLNA using net-misc/rygel
+media-sound/pragha:soup - Search metadata on AcoustID and radios on TuneIn using net-libs/libsoup
+media-sound/puddletag:acoustid - Use media-libs/chromaprint for acoustic fingerprinting
+media-sound/puddletag:cover - Enables editing of FLAC cover art
+media-sound/puddletag:musicbrainz - Enables support for musicbrainz, needs dev-python/python-musicbrainz
+media-sound/puddletag:quodlibet - Enables support for editing media-sound/quodlibet databases
+media-sound/pulseaudio:X - Build the X11 publish module to export PulseAudio information through X11 protocol for clients to make use. Don't enable this flag if you want to use a system wide instance. If unsure, enable this flag.
+media-sound/pulseaudio:alsa-plugin - Request installing media-plugins/alsa-plugins with PulseAudio plugin enabled. This ensures that clients supporting ALSA only will use PulseAudio.
+media-sound/pulseaudio:asyncns - Use libasyncns for asynchronous name resolution.
+media-sound/pulseaudio:doc - Build the doxygen-described API documentation.
+media-sound/pulseaudio:equalizer - Enable the equalizer module (requires sci-libs/fftw).
+media-sound/pulseaudio:gdbm - Use sys-libs/gdbm to store PulseAudio databases. Recommended for desktop usage. This flag causes the whole package to be licensed under GPL-2 or later.
+media-sound/pulseaudio:glib - Add support to dev-libs/glib-based mainloop for the libpulse client library, to allow using libpulse on glib-based programs.
+media-sound/pulseaudio:gnome - Use GConf to store user preferences on streams and so on. Don't enable this flag if you want to use a system wide instance. If unsure, enable this flag.
+media-sound/pulseaudio:native-headset - Build with native HSP backend for bluez 5.
+media-sound/pulseaudio:ofono-headset - Build with oFono HFP backend for bluez 5, requires net-misc/ofono.
+media-sound/pulseaudio:oss - Enable OSS sink/source (output/input). Deprecated, upstream does not support this on systems where other sink/source systems are available (i.e.: Linux). The padsp wrapper is now always build if the system supports OSS at all.
+media-sound/pulseaudio:realtime - Makes PulseAudio use RealtimeKit (sys-auth/rtkit) to get real-time priority while running.
+media-sound/pulseaudio:ssl - Use dev-libs/openssl to provide support for RAOP (AirPort) streaming.
+media-sound/pulseaudio:system-wide - Allow preparation and installation of the system-wide init script for PulseAudio. Since this support is only supported for embedded situations, do not enable without reading the upstream instructions at https://www.freedesktop.org/wiki/Software/PulseAudio/Documentation/User/WhatIsWrongWithSystemWide/ .
+media-sound/pulseaudio:systemd - Build with sys-apps/systemd support to replace standalone ConsoleKit.
+media-sound/pulseaudio:webrtc-aec - Uses the webrtc.org AudioProcessing library for enhancing VoIP calls greatly in applications that support it by performing acoustic echo cancellation, analog gain control, noise suppression and other processing.
+media-sound/qmidiarp:lv2 - Enables Ladspa V2 plugins.
+media-sound/qmmp:analyzer - Enable visual analyzer
+media-sound/qmmp:archive - Enable archiving plugin via app-arch/libarchive.
+media-sound/qmmp:bs2b - Enable Bauer stereophonic-to-binaural headphone filter
+media-sound/qmmp:cover - Enable album cover support
+media-sound/qmmp:crossfade - Enable crossfade effect when switching tracks
+media-sound/qmmp:cue - enable CUE sheet parsing
+media-sound/qmmp:dbus - Enable DBus notifiications and MPRIS support
+media-sound/qmmp:enca - Detects the character encoding automatically
+media-sound/qmmp:game - Enable Game music support
+media-sound/qmmp:gnome - Enable Gnome hotkey support (requires Qt5DBus)
+media-sound/qmmp:lyrics - Fetch track lyrics from the web
+media-sound/qmmp:midi - Enable midi support using wildmidi library
+media-sound/qmmp:notifier - Enable qmmps' notifier system
+media-sound/qmmp:opus - Enable the opus plugin
+media-sound/qmmp:projectm - Enable projectm music visualization plugin
+media-sound/qmmp:qsui - Enable QMMP simple UI
+media-sound/qmmp:qtmedia - Enable playback via dev-qt/qtmultimedia
+media-sound/qmmp:scrobbler - Enable audioscrobbler/last.fm support
+media-sound/qmmp:shout - Enable shoutcast plug-in via media-libs/libshout.
+media-sound/qmmp:sid - Build with SID (Commodore 64 Audio) support
+media-sound/qmmp:soxr - Use the SoX resampling library
+media-sound/qmmp:stereo - Enable stereo effect
+media-sound/qmmp:tray - Build tray icon
+media-sound/qsampler:libgig - Enable libgig support for loading Gigasampler files and DLS (Downloadable Sounds) Level 1/2 files
+media-sound/qtractor:dssi - Enable support for DSSI Soft Synth Interface
+media-sound/qtractor:rubberband - Enable support for in-place audio clip pitch-shifting through the rubberband library
+media-sound/qtscrobbler:cli - Build commandline client
+media-sound/quark:gnome - Provides tray-icon and enables gconf support
+media-sound/rhythmbox:daap - Build the local network music sharing plugin which uses the DAAP protocol using net-libs/libdmapsharing
+media-sound/rhythmbox:visualizer - Enable support for visualizations using media-plugins/gst-plugins-libvisual
+media-sound/shntool:alac - Add support for Apple Lossless Audio Codec files
+media-sound/shntool:mac - Add support for Monkey's Audio files
+media-sound/snd:s7 - Enable the s7 extension language (a version of Scheme)
+media-sound/sonata:lyrics - Support for lyrics fetching
+media-sound/sonata:trayicon - Enable support for trayicon
+media-sound/sonic-visualiser:id3tag - Enables ID3 tagging with id3tag library
+media-sound/soundconverter:opus - Enable Opus audio codec support
+media-sound/sox:amr - Enables Adaptive Multi-Rate Audio support
+media-sound/sox:id3tag - Enables ID3 tagging with id3tag library
+media-sound/sox:opus - Enables reading Ogg Opus files.
+media-sound/sox:twolame - Enables twolame support (MPEG Audio Layer 2 encoder)
+media-sound/split2flac:enca - Try to guess the charset using enca
+media-sound/split2flac:flake - Add support for Flake, alternative FLAC encoder
+media-sound/split2flac:mac - Add support for Monkey's Audio files
+media-sound/split2flac:replaygain - Support for Replay Gain metadata, for relative volume adjustment
+media-sound/spotify:pax_kernel - Triggers a paxmarking of the main Spotify binary
+media-sound/spotify:systray - Pulls in dependencies needed for systray support on some desktop environments
+media-sound/supercollider:emacs - Enable the SCEL user interface
+media-sound/supercollider:gedit - Enable the SCED user interface
+media-sound/supercollider:gpl3 - Build GPL-3 licensed code (recommended)
+media-sound/supercollider:server - Build with internal server
+media-sound/supercollider:vim - Enable the SCVIM user interface
+media-sound/supercollider:wiimote - Build sclang with Wii Remote support
+media-sound/teamspeak-server-bin:tsdns - Make use of TeamSpeak DNS.
+media-sound/tomahawk:hatchet - Enable support for the synchronisation through Hatchet
+media-sound/tomahawk:telepathy - Enable support for the real-time communication framework telepathy
+media-sound/traverso:lv2 - Add support for Ladspa V2
+media-sound/tuxguitar:fluidsynth - Enables Fluidsynth MIDI software synthesis (with external sound fonts). JSA must be disabled in the plug-ins menu to use this.
+media-sound/tuxguitar:lilypond - Exports the score in a lilypond compatible format.
+media-sound/tuxguitar:pdf - Exports the score as a PDF file using dev-java/itext.
+media-sound/tuxguitar:tray - Adds an icon to the tray that controls midi playback.
+media-sound/umurmur:shm - Enable shared memory support
+media-sound/upmpdcli:thirdparty - Enable streaming from Qobuz and Tidal external services
+media-sound/vimpc:boost - Use boost instead of C++11 libraries
+media-sound/vorbis-tools:kate - Adds support for Ogg Kate subtitles via libkate.
+media-sound/vorbis-tools:ogg123 - Build ogg123 player, needs libao and curl
+media-sound/wildmidi:player - Install the wildmidi player
+media-sound/xmms2:airplay - Support for airplay format
+media-sound/xmms2:asf - Support for Monkey's Audio (APE) format with help of bundled libasf
+media-sound/xmms2:fluidsynth - Enable fluidsynth support (MIDI)
+media-sound/xmms2:gvfs - Transport for glibs virtual filesystem
+media-sound/xmms2:ices - Icecast source output plugin
+media-sound/xmms2:mac - Support for Monkey's Audio (APE) format with help of media-sound/mac
+media-sound/xmms2:mlib-update - Enable building of xmms2-mlib-updater client
+media-sound/xmms2:ofa - Support for Open Fingerprint Architecture (OFA)
+media-sound/xmms2:opus - Enable Opus audio codec support
+media-sound/xmms2:phonehome - This client sends anonymous usage-statistics to the xmms2
+media-sound/xmms2:server - Build xmms2 player daemon (otherwise only clients are built)
+media-sound/xmms2:sid - Support for C64 SID
+media-sound/xmms2:valgrind - Run unit tests under valgrind.
+media-sound/xmms2:vocoder - Phase vocoder effect plugin
+media-sound/xmms2:xml - Enable support for various XML based playlists and sources: RSS, XSPF
+media-sound/xnoise:lastfm - Enable support for lastfm cover art fetching and scrobbling
+media-sound/xnoise:lyrics - Enable support for lyrics fetching
+media-sound/xwax:alsa - Adds support for ALSA audio input/output.
+media-sound/xwax:cdda - Sets runtime dependencies to support decoding audio from a compact disc.
+media-sound/xwax:fallback - Sets runtime dependencies to support decoding "other" audio files.
+media-sound/xwax:jack - Adds support for audio input/output via the JACK Audio Connection Kit.
+media-sound/xwax:mp3 - Sets runtime dependencies to support decoding MP3 audio.
+media-sound/xwax:oss - Adds support for OSS (open sound system) audio input/output.
+media-sound/yoshimi:lv2 - Add support for Ladspa V2
+media-tv/gentoo-vdr-scripts:nvram - Add support for using nvram-wakeup to set wakeup time in bios
+media-tv/kodi:airplay - enable AirPlay support
+media-tv/kodi:bluray - Enable playback of Blu-ray filesystems
+media-tv/kodi:cec - Enable support for HDMI-CEC devices via libcec
+media-tv/kodi:dvd - Enable optical (CD/DVD drive) support
+media-tv/kodi:gbm - Use the Graphics Buffer Manager for EGL on KMS.
+media-tv/kodi:gles - Enable support for GLES
+media-tv/kodi:libusb - Use virtual/libusb for usb device hotplug support. This flag should only be enabled if you're running a non-Linux kernel or you don't want to use sys-fs/udev.
+media-tv/kodi:lirc - Enable support for controlling Totem with a remote control using app-misc/lirc
+media-tv/kodi:nfs - Enable NFS client support
+media-tv/kodi:nonfree - Enable non-free components
+media-tv/kodi:sftp - Support browsing files over SFTP
+media-tv/kodi:system-ffmpeg - Use system ffmpeg instead of the bundled one
+media-tv/kodi:udev - Use sys-fs/udev rules to handle devices' permissions and hotplug support. Unless you know what you're doing do not disable this flag on Linux kernels. This is provided as an option for completeness.
+media-tv/kodi:webserver - Enable internal webserver
+media-tv/kodi:xslt - Enable XSLT support using dev-libs/libxslt
+media-tv/linuxtv-dvb-apps:alevt - Build videotext decoder
+media-tv/me-tv:http - Installation of Web-frontend
+media-tv/mythtv:alsa - Allows MythTV to directly output sound to ALSA devices, this is needed if you are using ALSA dmix or SPDIF. Note, you will have to physically type your device into the MythTV configuration since it will only give you /dev/dsp devices in the drop down.
+media-tv/mythtv:altivec - Builds ffmpeg's codec libraries with altivec support.
+media-tv/mythtv:autostart - Uses a custom autostart configuration gleaned from experience with MythTV since its early versions and discussed with other MythTV maintainers and users. Does not rely on KDE being installed like most methods do.
+media-tv/mythtv:bluray - Pulls in libbluray for BluRay support.
+media-tv/mythtv:cec - Allows you to control CEC enabled TVs via HDMI. Currently requires a USB based CEC -> HDMI injector between your TV and video card since no graphics drivers support CEC natively.
+media-tv/mythtv:crystalhd - Allows you to utilize a Broadcom CrystalHD hardware based video decoder to improve the performance of video decode.
+media-tv/mythtv:debug - Instructs Qt to use the 'debug' target instead of 'release' target. If your MythTV is crashing or you need a backtrace, you need to compile it with this option otherwise the debugging data is useless.
+media-tv/mythtv:egl - Support EGL video output.
+media-tv/mythtv:fftw - Support visualizations via sci-libs/fftw
+media-tv/mythtv:hls - HTTP Live Streaming support
+media-tv/mythtv:ieee1394 - Allows MythTV to communicate and use Firewire enabled Cable boxes. These are typically found in the United States, where such support is required by law. This will also install Firewire test programs and external channel changers if the internal changer does not work.
+media-tv/mythtv:jack - Allows MythTV to use JACK as your sound output device. You will have to manually configure the path to your JACK settings.
+media-tv/mythtv:lcd - Tells MythTV that you have an instance of app-misc/lcdproc configured on your machine and it should output information such as current time, show name, episode name, etc to that LCD.
+media-tv/mythtv:lirc - Adds LIRC support directly to MythTV allowing for built in control via a LIRC device.
+media-tv/mythtv:mythlogserver - Enable support for syslog and file logging. Not used with systemd.
+media-tv/mythtv:perl - Builds the perl bindings for MythTV. Allows you to write scripts in Perl to control your MythTV setup or communicate with it.
+media-tv/mythtv:wrapper - Use Ubuntu mythtfrontend wrapper.
+media-tv/mythtv:xmltv - Pulls in the media-tv/xmltv TV listing grabbers for users not using Schedules Direct.
+media-tv/tvbrowser:themes - Install extra theme packs
+media-tv/tvheadend:capmt - Enable support for capmt (dvbapi) protocol
+media-tv/tvheadend:constcw - Enable support for the constcw protocol
+media-tv/tvheadend:cwc - Enable support for the cwc (newcamd) protocol
+media-tv/tvheadend:ddci - Enable support for DDCI hardware
+media-tv/tvheadend:dvbcsa - Enable decryption of the DVB Common Scrambling Algorithm
+media-tv/tvheadend:dvben50221 - Enable support for hardware CAM
+media-tv/tvheadend:hdhomerun - Enable support for the HDHomeRun device
+media-tv/tvheadend:imagecache - Enable support for image caching
+media-tv/tvheadend:iptv - Enable support for Internet Protocol TV
+media-tv/tvheadend:opus - Enable transcoding with the Opus audio codec
+media-tv/tvheadend:satip - Enable support for IP-based Satellite TV
+media-tv/tvheadend:timeshift - Enable TimeShift support
+media-tv/tvheadend:uriparser - Use dev-libs/uriparser
+media-tv/tvheadend:vpx - Enable transcoding with the VP8/VP9 video codecs
+media-tv/tvheadend:x264 - Enable transcoding with the H.264 video codec
+media-tv/tvheadend:x265 - Enable transcoding with the HEVC video codec
+media-tv/tvheadend:xmltv - Use media-tv/xmltv
+media-tv/v4l-dvb-saa716x:firmware - Install firmware
+media-tv/xmltv:ar - Argentina tv listing grabber
+media-tv/xmltv:ch - Switzerland bluewin tv listing grabber
+media-tv/xmltv:ch_search - Grabber for Switzerland
+media-tv/xmltv:dk - Denmark tv listing grabber
+media-tv/xmltv:dtvla - Latin America digital tv listing grabber
+media-tv/xmltv:ee - Estonia tv listing grabber
+media-tv/xmltv:es_laguiatv - Spain alternative grabber
+media-tv/xmltv:es_miguiatv - Spain alternative grabber
+media-tv/xmltv:eu_dotmedia - Grabber for Europe (xmltv.se / dotmedia)
+media-tv/xmltv:eu_egon - Grabber for german speaking area (Egon zappt)
+media-tv/xmltv:eu_epg - EPG grabber for some European countries.
+media-tv/xmltv:fi - Finland tv listing grabber
+media-tv/xmltv:fi_sv - Grabber for Finland (Swedish)
+media-tv/xmltv:fr - France tv listing grabber
+media-tv/xmltv:fr_kazer - France (Kazer) tv listing grabber
+media-tv/xmltv:hr - Croatia tv listing grabber
+media-tv/xmltv:huro - Hungarian tv listing grabber
+media-tv/xmltv:il - Israel tv listing grabber
+media-tv/xmltv:in - India tv listing grabber
+media-tv/xmltv:is - Iceland tv listing grabber
+media-tv/xmltv:it - Italy tv listing grabber
+media-tv/xmltv:na_dd - North America tv listing grabber
+media-tv/xmltv:na_dtv - North America Direct TV grabber
+media-tv/xmltv:na_icons - option for na_dd to download icons
+media-tv/xmltv:na_tvmedia - Grabber for North America (TVMedia)
+media-tv/xmltv:nl - Netherlands tv listing grabber
+media-tv/xmltv:no_gf - Norway Gfeed tv listing grabber
+media-tv/xmltv:pt - Portugal tv listing grabber
+media-tv/xmltv:pt_meo - Grabber for Portugal (MEO)
+media-tv/xmltv:re - Reunion Island (France) tv listing grabber
+media-tv/xmltv:sd_json - Grabber for schedulesDirect.org SD-JSON service (many countries)
+media-tv/xmltv:se_swedb - Sweden tv listing grabber
+media-tv/xmltv:se_tvzon - Sweden (tvzon.se) tv listing grabber
+media-tv/xmltv:tr - Turkey (Digiturk) tv listing grabber
+media-tv/xmltv:tv_check - enable GUI checking
+media-tv/xmltv:tv_combiner - enable grabbers combiner
+media-tv/xmltv:tv_pick_cgi - enable CGI support
+media-tv/xmltv:uk_atlas - Fast UK and Ireland tv listing grabber
+media-tv/xmltv:uk_bleb - Britain tv listing grabber
+media-tv/xmltv:uk_rt - Britain alternative tv listing grabber
+media-tv/xmltv:uk_tvguide - UK and Ireland tv listing grabber using TV Guide website
+media-tv/xmltv:za - South Africa tv listing grabber
+media-tv/xmltv:zz_sdjson - Grabber for schedulesDirect.org SD-JSON service (many countries)
+media-video/aegisub:uchardet - Enable charset discovery via app-i18n/uchardet
+media-video/aravis:X - Build the GTK+-based video viewer for aravis. This requires GStreamer and a few plugins but technically not the GST plugin for aravis.
+media-video/aravis:gstreamer - Build the GStreamer plugin for aravis, but not the video viewer.
+media-video/avidemux:nvenc - Adds support for NVIDIA Encoder (NVENC) API for hardware accelerated encoding on NVIDIA cards.
+media-video/chaplin:transcode - Enable DVD ripping and transcoding
+media-video/clive:clipboard - Support reading from X clipboard
+media-video/clive:pager - Support pager!?
+media-video/clive:password - Support password controlled sites
+media-video/dcpomatic:alsa - Utilize alsa output of media-libs/rtaudio.
+media-video/dcpomatic:jack - Utilize jack output of media-libs/rtaudio.
+media-video/dcpomatic:pulseaudio - Utilize pulseaudio output of media-libs/rtaudio.
+media-video/dv2sub:kino - install kino plugin
+media-video/dvdrip:fping - Enables fping support for cluster rendering
+media-video/dvdrip:subtitles - Enables support for subtitle ripping
+media-video/ffdiaporama:openclipart - Support openclipart database
+media-video/ffdiaporama:texturemate - Install extra backgrounds
+media-video/ffmpeg:amr - Enables Adaptive Multi-Rate Audio support
+media-video/ffmpeg:amrenc - Enables Adaptive Multi-Rate Audio encoding support with media-libs/vo-amrwbenc.
+media-video/ffmpeg:appkit - Enables Apple AppKit framework
+media-video/ffmpeg:armv5te - Enables optimizations for armv5te processors.
+media-video/ffmpeg:armv6 - Enables optimizations for armv6 processors.
+media-video/ffmpeg:armv6t2 - Enables optimizations for armv6t2 processors.
+media-video/ffmpeg:armvfp - Enables VFP optimizations for ARM processors.
+media-video/ffmpeg:bluray - Enable playback of Blu-ray filesystems
+media-video/ffmpeg:bs2b - Enables media-libs/libbs2b based Bauer stereo-to-binaural filter.
+media-video/ffmpeg:cdio - Enables audio CD grabbing with dev-libs/libcdio.
+media-video/ffmpeg:celt - Adds Xiph CELT audio decoding support via media-libs/celt
+media-video/ffmpeg:chromaprint - Enables audio fingerprinting support with media-libs/chromaprint.
+media-video/ffmpeg:chromium - Builds libffmpeg.so to enable media playback in Chromium-based browsers like Opera and Vivaldi.
+media-video/ffmpeg:cpudetection - Enables runtime CPU detection (useful for bindist, compatibility on other CPUs)
+media-video/ffmpeg:ebur128 - Enables EBU R128 loudness normalization filter via media-libs/libebur128
+media-video/ffmpeg:fdk - Use external fdk-aac library for AAC encoding
+media-video/ffmpeg:flite - Adds a text-to-speech filter based on app-accessibility/flite.
+media-video/ffmpeg:frei0r - Enable frei0r wrapping in libavfilter
+media-video/ffmpeg:fribidi - Enables fribidi support in the drawtext filter.
+media-video/ffmpeg:gcrypt - Enables gcrypt support: Needed for rtmp(t)e support if openssl, librtmp or gmp is not used.
+media-video/ffmpeg:gme - Enables support for media-libs/game-music-emu for playing various video game music formats.
+media-video/ffmpeg:gpl - Build GPL code. Should be enabled unless you require LGPL binaries.
+media-video/ffmpeg:hardcoded-tables - Use pre-calculated tables rather than calculating them on the fly.
+media-video/ffmpeg:iec61883 - Support for FireWire DV/HDV input device using media-libs/libiec61883.
+media-video/ffmpeg:kvazaar - Enables media-libs/kvazaar based HEVC encoder.
+media-video/ffmpeg:libdrm - Enables x11-libs/libdrm support for better screen grabbing and hardware accelerated codecs.
+media-video/ffmpeg:libilbc - Enables iLBC de/encoding via media-libs/libilbc.
+media-video/ffmpeg:librtmp - Enables Real Time Messaging Protocol using librtmp (media-video/rtmpdump) in addition to FFmpeg's native implementation.
+media-video/ffmpeg:libsoxr - Enables audio resampling through media-libs/soxr.
+media-video/ffmpeg:libv4l - Uses media-libs/libv4l for video4linux instead of direct calls. Adds support for more devices via the userspace library.
+media-video/ffmpeg:mipsdspr1 - Enables MIPS DSP ASE R1 optimizations.
+media-video/ffmpeg:mipsdspr2 - Enables MIPS DSP ASE R2 optimizations.
+media-video/ffmpeg:mipsfpu - Enables floating point MIPS optimizations.
+media-video/ffmpeg:mmal - Enables Multi-Media Abstraction Layer (MMAL) decoding support: Available e.g. on the Raspberry Pi.
+media-video/ffmpeg:network - Enables network streaming support
+media-video/ffmpeg:nvenc - Adds support for NVIDIA Encoder (NVENC) API for hardware accelerated encoding on NVIDIA cards.
+media-video/ffmpeg:openh264 - Enables H.264 encoding suppoprt via media-libs/openh264.
+media-video/ffmpeg:openssl - Enables dev-libs/openssl support. Adds support for encrypted network protocols (TLS/HTTPS).
+media-video/ffmpeg:opus - Adds (decoding) support for the Opus codec via media-libs/opus.
+media-video/ffmpeg:pic - Force shared libraries to be built as PIC (this is slower)
+media-video/ffmpeg:postproc - Build and install libpostproc.
+media-video/ffmpeg:rubberband - Adds time-stretching and pitch-shifting audio filter based on media-libs/rubberband.
+media-video/ffmpeg:schroedinger - Enable Dirac video support (an advanced royalty-free video compression format) via libschroedinger (high-speed implementation in C of the Dirac codec).
+media-video/ffmpeg:snappy - Enable app-arch/snappy support. Required for e.g. Vidvox Hap encoder.
+media-video/ffmpeg:sofalizer - Enables Sofalizer filter
+media-video/ffmpeg:ssh - Enable SSH/sftp support via net-libs/libssh.
+media-video/ffmpeg:twolame - Enables MP2 encoding via media-sound/twolame as an alternative to the internal encoder.
+media-video/ffmpeg:vpx - Enables vp8 codec support using libvpx: Decoding vp8 does not require this to be enabled but libvpx can also be used for decoding; encoding vp8 requires this useflag to be enabled though.
+media-video/ffmpeg:webp - Enables WebP encoding with media-libs/libwebp.
+media-video/ffmpeg:x265 - Enables HEVC encoding with media-libs/x265.
+media-video/ffmpeg:zeromq - Enables net-libs/zeromq support with the zmq/azmq filters.
+media-video/ffmpeg:zimg - Enables media-libs/zimg based scale filter.
+media-video/ffmpeg:zvbi - Enables media-libs/zvbi based teletext decoder.
+media-video/ffmpeg2theora:kate - Adds support for Ogg Kate subtitles via libkate.
+media-video/gnome-mplayer:dconf - Enable support for gnome-base/dconf
+media-video/gnome-mplayer:gda - Enable support for gnome-extra/libgda
+media-video/google2srt:html - Install HTML documentation
+media-video/h264enc:ogm - Support for OGM container format
+media-video/handbrake:fdk - Support for encoding AAC using media-libs/fdk-aac.
+media-video/handbrake:gstreamer - Support for the streaming media framework from media-libs/gstreamer.
+media-video/handbrake:gtk - Install the GTK UI, ghb.
+media-video/handbrake:libav-aac - Support for encoding AAC using media-video/libav's internal encoder.
+media-video/handbrake:x265 - Support for encoding h265 using media-libs/x265.
+media-video/kino:gpac - Enable GPAC support when exporting to 3GPP format
+media-video/kmplayer:npp - Compile the npp backend that plays xembed style browser plugins.
+media-video/libav:aac - Use external vo-aacenc library for AAC encoding
+media-video/libav:amr - Enable Adaptive Multi-Rate Audio support
+media-video/libav:armv5te - Enable optimizations for armv5te processors
+media-video/libav:armv6 - Enable optimizations for armv6 processors
+media-video/libav:armv6t2 - Enable optimizations for armv6t2 processors
+media-video/libav:armvfp - Enable VFP optimizations for ARM processors
+media-video/libav:bs2b - Enable media-libs/libbs2b based Bauer stereo-to-binaural audio filter
+media-video/libav:cdio - Enable audio CD grabbing with dev-libs/libcdio.
+media-video/libav:cpudetection - Enables runtime CPU detection (useful for bindist, compatibility on other CPUs).
+media-video/libav:faac - Use external faac library for AAC encoding
+media-video/libav:fdk - Use external fdk-aac library for AAC encoding and decoding
+media-video/libav:frei0r - Enable frei0r wrapping in libavfilter
+media-video/libav:gpl - Build all GPL licensed code. Without this flag set the package is build under LGPL license.
+media-video/libav:hardcoded-tables - Use pre-calculated tables rather than calculating them on the fly.
+media-video/libav:network - Enable network streaming support.
+media-video/libav:nvidia - Enable nvidia video codec hardware acceleration support.
+media-video/libav:openssl - Prefer dev-libs/openssl over net-libs/gnutls to provide SSL/TLS support (notice: the resulting binaries are unredistributable).
+media-video/libav:opus - Use the external opus library for encoding and decoding.
+media-video/libav:pic - Force shared libraries to be built as PIC (this is slower).
+media-video/libav:pulseaudio - Enable pulseaudio input support.
+media-video/libav:rtmp - Enable Real Time Messaging Protocol using librtmp instead the native implementation.
+media-video/libav:schroedinger - Enable Dirac video support (an advanced royalty-free video compression format) via libschroedinger (high-speed implementation in C of the Dirac codec).
+media-video/libav:ssl - Enable SSL/TLS support using dev-libs/openssl or net-libs/gnutls.
+media-video/libav:tools - Build and install small tools like aviocat, cws2fws, graph2dot, ismindex, qt-faststart.
+media-video/libav:twolame - Enable MP2 encoding via media-sound/twolame as an alternative to the internal encoder
+media-video/libav:vis - Adds support for SIMD optimizations for UltraSPARC processors.
+media-video/libav:vpx - Enable vp8 encoding support using media-libs/libvpx.
+media-video/libav:webp - Enable WebP encoding with media-libs/libwebp.
+media-video/libav:x265 - Enable HEVC encoding with media-libs/x265.
+media-video/libva-utils:drm - Enables VA/DRM API support.
+media-video/makemkv:gui - Build the Qt5 GUI
+media-video/minitube:download - Enable support for downloading YouTube videos
+media-video/mjpegtools:sdlgfx - Enables y4mhist to display a graphical histogram
+media-video/mjpg-streamer:input_control - Plugin giving ability to control camera movement (only specific cameras)
+media-video/mjpg-streamer:input_file - Plugin that watches given directory and send it's content
+media-video/mjpg-streamer:input_testpicture - Plugin for sending compiled in, test pictures
+media-video/mjpg-streamer:input_uvc - Plugin that sends video stream from UVC compatible camera
+media-video/mjpg-streamer:output_autofocus - Auto focusing plugin
+media-video/mjpg-streamer:output_file - Plugin that saves received content under given location
+media-video/mjpg-streamer:output_http - Small HTTP server plugin which sends WWW directory content and streams image content
+media-video/mjpg-streamer:output_rtsp - Plugin which provides a mechanism to take snapshots with a trigger from a UDP packet
+media-video/mjpg-streamer:output_udp - Plugin receiving content over UDP and storing to a directory
+media-video/mjpg-streamer:v4l - Uses media-libs/libv4l function mapping for input_uvc plugin
+media-video/mjpg-streamer:www - Installs WWW content
+media-video/motion:mmal - Enables Multi-Media Abstraction Layer (MMAL) decoding support: Available e.g. on the Raspberry Pi.
+media-video/motiontrack:multiprocess - Enables multi-process support (SMP/cluster) for motiontrack programs
+media-video/mplayer:bl - Blinkenlights video output
+media-video/mplayer:bluray - Enable playback of Blu-ray filesystems
+media-video/mplayer:bs2b - Enable Bauer stereophonic-to-binaural headphone filter
+media-video/mplayer:cdio - Use libcdio for CD support (instead of cdparanoia)
+media-video/mplayer:cpudetection - Enables runtime CPU detection (useful for binpkgs, compatibility on other CPUs)
+media-video/mplayer:dvdnav - Use forked libdvdnav, navigate menus in GUIs
+media-video/mplayer:enca - Enables support for charset discovery and conversion
+media-video/mplayer:faac - Use external faac library for AAC encoding
+media-video/mplayer:faad - Use external faad library for AAC decoding
+media-video/mplayer:libmpeg2 - Build support for mpeg2 over media-libs/libmpeg2 rather than using ffmpeg.
+media-video/mplayer:live - Enables live.com streaming media support
+media-video/mplayer:md5sum - Enables md5sum video output
+media-video/mplayer:mng - MNG input support
+media-video/mplayer:network - Enables network streaming support
+media-video/mplayer:nut - Enables support for the NUT container format
+media-video/mplayer:osdmenu - Enables support for on-screen display (OSD) menus
+media-video/mplayer:pnm - Add PNM video output option, to create PPM/PGM/PGMYUV images
+media-video/mplayer:pvr - Enable Video4Linux2 MPEG PVR
+media-video/mplayer:radio - Enable V4L2 radio interface and support
+media-video/mplayer:rar - Enable Unique RAR File Library
+media-video/mplayer:rtc - Enables usage of the linux real time clock. The alternative is software emulation of rtc
+media-video/mplayer:rtmp - Enables RTMPDump Streaming Media support
+media-video/mplayer:shm - Enable support for shm
+media-video/mplayer:tga - Enables Targa video output
+media-video/mplayer:toolame - Enable toolame MPEG-2 encoding
+media-video/mplayer:tremor - Enable internal support for Vorbis
+media-video/mplayer:twolame - Enable twolame MPEG-2 encoding
+media-video/mplayer:vcd - Enables VCD support
+media-video/mplayer:vidix - Support for vidix video output
+media-video/mplayer:xvmc - Enables X-Video Motion Compensation support
+media-video/mplayer:yuv4mpeg - Enables yuv4mpeg video output
+media-video/mplayer:zoran - Enables ZR360[56]7/ZR36060 video output
+media-video/mpv:archive - Enable support for various archive formats via app-arch/libarchive
+media-video/mpv:bluray - Enable playback of Blu-ray filesystems
+media-video/mpv:cli - Build mpv CLI player
+media-video/mpv:cplugins - Enable C plugins support
+media-video/mpv:cuda - Enable hardware video decoding via Nvidia CUDA
+media-video/mpv:drm - Enable Kernel Mode Setting / Direct Rendering Manager based video output
+media-video/mpv:egl - Enable support for various EGL-based video outputs / backends
+media-video/mpv:gbm - Enable Graphics Buffer Manager based EGL video backend
+media-video/mpv:jpeg - Enable support for saving screenshots in JPEG format
+media-video/mpv:libass - Enable OSD (On Screen Display) and subtitles support via media-libs/libass
+media-video/mpv:libmpv - Build mpv shared library
+media-video/mpv:lua - Enable Lua scripting, OSC (On Screen Controller) GUI and net-misc/youtube-dl hook-script
+media-video/mpv:luajit - Use dev-lang/luajit instead of dev-lang/lua
+media-video/mpv:opengl - Enable the recommended 'opengl' video output
+media-video/mpv:raspberry-pi - Enable support for the Raspberry Pi
+media-video/mpv:rubberband - Enable high quality pitch correction via media-libs/rubberband
+media-video/mpv:sdl - Enable media-libs/libsdl2 based video and audio outputs (Note: these outputs exist for compatibility reasons only, avoid if possible)
+media-video/mpv:tools - Install extra tools: mpv_identify.sh, mpv_idet.sh, and umpv
+media-video/mpv:uchardet - Enable subtitles charset discovery via app-i18n/uchardet
+media-video/mpv:vf-dlopen - Install additional video filters to be used with -vf dlopen
+media-video/noad:libmpeg2 - Support for libmpeg2 library
+media-video/nvidia-settings:gtk3 - Additionally build the GTK 3 library
+media-video/nvidia_video_sdk:tools - Build and install example tools.
+media-video/obs-studio:fdk - Enable libfdk support for AAC encoding.
+media-video/obs-studio:imagemagick - Use ImageMagick for image loading instead of FFmpeg.
+media-video/ogmrip:ogm - Support for OGM container format
+media-video/ogmrip:srt - Support for SRT subtitle format
+media-video/orion:mpv - Use the media-video/mpv player (upstream default) instead of the dev-qt/qtmultimedia one
+media-video/parole:clutter - Compile in Clutter GTK+ support
+media-video/peek:keybinder - Enable support for global hotkeys using dev-libs/keybinder
+media-video/rtmpdump:gnutls - Use GnuTLS library instead of the default OpenSSL
+media-video/simplescreenrecorder:asm - Enable x86 assembly optimisation.
+media-video/simplescreenrecorder:vpx - Enable VP8 codec support via media-libs/libvpx.
+media-video/smplayer:autoshutdown - Enable the option to shutdown your computer after finishing the playlist. This requires dev-qt/qtdbus as dependency.
+media-video/smplayer:mpris - Enable support for MPRIS2 (Media Player Remote Interfacing Specification, version 2), a DBus interface for remote control, which requires dev-qt/qtdbus as dependency.
+media-video/subtitlecomposer:mpv - Build mpv backend support
+media-video/syncplay:client - Install Syncplay client
+media-video/syncplay:gui - Enable gui support
+media-video/syncplay:server - Install Syncplay server
+media-video/syncplay:vlc - Enable VLC2.x support
+media-video/totem:lirc - Enable support for controlling Totem with a remote control using app-misc/lirc
+media-video/totem:nautilus - Enable the nautilus extension
+media-video/totem:python - Build support for dev-lang/python plugins
+media-video/transcode:mjpeg - Enables mjpegtools support
+media-video/transcode:nuv - NuppelVideo container format demuxing
+media-video/transcode:pic - disable optimized assembly code that is not PIC friendly
+media-video/transcode:postproc - Build with ffmpeg libpostproc support
+media-video/vdr:alternatechannel - Use alternate channel on record
+media-video/vdr:bidi - fribidi support, for languages, written from right to left
+media-video/vdr:ddepgentry - remove duplicate EPG entries
+media-video/vdr:dvlvidprefer - controls video-dir choice on recording
+media-video/vdr:graphtft - support for media-plugins/vdr-graphtftplugin up from version 0.1.7
+media-video/vdr:html - Install HTML documentation
+media-video/vdr:jumpingseconds - skip seconds in played records
+media-video/vdr:jumpplay - Enables automatic jumping over cut marks while watching a recording
+media-video/vdr:kbd - enable keyboard support as remote device
+media-video/vdr:mainmenuhooks - Allows to replace main menu entries by some special plugins (like epgsearch, extrecmenu, ...)
+media-video/vdr:menuorg - Enables support for the media-plugins/vdr-menuorg
+media-video/vdr:menuselection - adds support for menu hotkeys of double digits
+media-video/vdr:naludump - Removes NALU fill data from h.264-Streams of TS files
+media-video/vdr:permashift - permanent timeshift by recording live TV on hard disk, need plugin media-plugins/vdr-permashift
+media-video/vdr:permashift_v1 - permanent timeshift by recording live TV on RAM, need plugin >=mediaplugins/vdr-permashift-1
+media-video/vdr:pinplugin - Support for media-plugins/vdr-pin
+media-video/vdr:resumereset - rreset resume of EOF
+media-video/vdr:rotor - Enable support for plugin media-plugins/vdr-rotor for dish-positioner.
+media-video/vdr:ttxtsubs - support for media-plugins/vdr-ttxtsubs
+media-video/vdr:vasarajanauloja - replacement for the liemikuutio patch, adds some nice must haves features
+media-video/vdr:wareagleicon - Replace original icon set in menu
+media-video/vdr:yaepg - Enables support for the vdr-yaepg plugin
+media-video/vlc:X - Enable support for, e.g., fullscreen mode via the X Window System. By itself, this flag does not build a graphical interface
+media-video/vlc:aom - Enable experimental support for AV1 codec
+media-video/vlc:archive - Enable support for libarchive stream extractor
+media-video/vlc:atmo - Enable support for AtmoLight (homebrew Ambient Lighting Technology)
+media-video/vlc:audioqueue - Enable AudioQueue audio module for Mac OS X
+media-video/vlc:avcodec - Enable libavcodec support for video/audio encoding/decoding. libavcodec is part of FFmpeg
+media-video/vlc:avformat - Enable libformat support for reading and writing various media containers. libavformat is part of FFmpeg
+media-video/vlc:bluray - Enable libbluray for Blu-ray disc support
+media-video/vlc:chromaprint - Enable libchromaprint for Chromaprint based audio fingerprinter support
+media-video/vlc:chromecast - Enable experimental support for Google Chromecast
+media-video/vlc:dc1394 - Enable IIDC cameras support
+media-video/vlc:directx - Enable Win32 DirectX support
+media-video/vlc:dvbpsi - Enable support for Mpeg-TS files (.ts, .m2ts, .mts) via media-libs/libdvbpsi
+media-video/vlc:dxva2 - Enable Win32 DxVA2 support
+media-video/vlc:encode - Enable streaming-output support and videolan manager to control multiple streams from within one instance
+media-video/vlc:faad - Enable AAC audio decoding library support via media-libs/faad2
+media-video/vlc:fdk - Enable the Fraunhofer AAC codec library
+media-video/vlc:fluidsynth - Enable Fluidsynth MIDI software synthesis (with external sound fonts)
+media-video/vlc:gcrypt - Enable cryptography support via libgcrypt
+media-video/vlc:gme - Enable support for media-libs/game-music-emu for playing various video game music formats
+media-video/vlc:gnome - Adds support for GNOME's filesystem abstraction layer, gnome-base/gnome-vfs. This flag is not GUI-related
+media-video/vlc:growl - Enable growl notification support (over UDP for remote access and native on OSX)
+media-video/vlc:gstreamer - Enable GStreamer based decoding support (currently supports only video decoding)
+media-video/vlc:httpd - Enable a web based interface for vlc
+media-video/vlc:kate - Adds support for Ogg Kate subtitles via libkate
+media-video/vlc:libtar - Uses libtar instead of the built-in tar reader for reading custom skins
+media-video/vlc:libtiger - Enable Ogg Kate subtitles rendering using libtiger
+media-video/vlc:linsys - Enable support for Linux Linear Systems Ltd. SDI and HD-SDI input cards
+media-video/vlc:live - Enable live555 streaming media support (client support for rtsp)
+media-video/vlc:lua - Enable Lua scripting support, needed for including support for Jamendo (online music platform) and similar things
+media-video/vlc:macosx-dialog-provider - Enable Mac OS X dialog module
+media-video/vlc:macosx-eyetv - Enable Mac OS X EyeTV (TNT Tuner) module
+media-video/vlc:macosx-notifications - Enable Mac OS X notifications module (formerly growl)
+media-video/vlc:macosx-qtkit - Enable Mac OS X qtkit module: qtcapture (video) and qtsound (audio) module
+media-video/vlc:macosx-quartztext - Enable Mac OS X quartz text module
+media-video/vlc:matroska - Enable matroska support using reference libraries (fallback on other existing matroska support if disabled, i.e., matroska enabled FFmpeg)
+media-video/vlc:microdns - Enable Chromecast auto-detection using net-libs/libmicrodns
+media-video/vlc:mpeg - Add libmpeg2 support for mpeg-1 and mpeg-2 video streams
+media-video/vlc:nfs - Enable support for nfs protocol via net-fs/libnfs
+media-video/vlc:omxil - Enable OpenMAX Integration Layer codec module
+media-video/vlc:opencv - Enable OpenCV (computer vision) filter module
+media-video/vlc:optimisememory - Enable optimisation for memory rather than performance
+media-video/vlc:opus - Support opus decoding via libopus
+media-video/vlc:postproc - Enable image post-processing via libpostproc (part of FFmpeg)
+media-video/vlc:projectm - Enable the projectM visualization plugin
+media-video/vlc:rtsp - Enable real audio and RTSP modules
+media-video/vlc:run-as-root - Allows vlc to start for root. Don't enable this unless you have a very specific (e.g. embedded) need for it!
+media-video/vlc:schroedinger - Enable Dirac video support (an advanced royalty-free video compression format) via libschroedinger (high-speed implementation in C of the Dirac codec)
+media-video/vlc:sdl-image - Enable sdl image video decoder (depends on sdl)
+media-video/vlc:sftp - Enable libssh2 to support SFTP file transfer
+media-video/vlc:shout - Enable libshout output
+media-video/vlc:sid - Adds support for playing C64 SID files through media-libs/libsidplay:2
+media-video/vlc:skins - Enable support for the skins2 interface
+media-video/vlc:swscale - Enable image scaling and conversion via libswscale (part of FFmpeg)
+media-video/vlc:tremor - Enable tremor, a fixed-point version of the Ogg Vorbis decoder
+media-video/vlc:twolame - Enable twolame support (MPEG Audio Layer 2 encoder)
+media-video/vlc:upnp - Enable support for the Intel SDK stack based UPnP discovery module instead of CyberLink
+media-video/vlc:vcdx - Enable VCD with navigation via libvcdinfo (depends on cdio)
+media-video/vlc:vlm - New videolan (media) manager (vlm), a little manager designed to launch and manage multiple streams from within one instance of VLC
+media-video/vlc:vpx - Enable the decoder(s) from the WebM VP8 / VP9 Codec SDK
+media-video/vlc:wma-fixed - Enable fixed point WMA decoder
+media-video/vlc:x265 - Support X265 Encoder
+media-video/vlc:xcb - Support the X C-language Binding, a replacement for Xlib; !!! you will need this option to be able to integrate video in the Qt interface, see bug #500678
+media-video/vlc:zeroconf - Enable support for zero-configuration networking via avahi
+media-video/vlc:zvbi - Enable support for teletext subtitles via the zvbi library
+media-video/webcamoid:headers - Install development headers
+media-video/webcamoid:libuvc - Build with libuvc support
+media-video/webcamoid:qtaudio - Enable audio capture/play via dev-qt/qtmultimedia
+media-video/webcamoid:v4lutils - Build with V4L-utils support
+media-video/webcamoid:videoeffects - Build video effects
+media-video/x264-encoder:10bit - Set output bit depth to 10
+media-video/x264-encoder:avs - enable AvxSynth support in the AviSynth input module
+media-video/x264-encoder:ffmpegsource - Enable ffmpegsource aka ffms support, disables lavf
+media-video/x264-encoder:interlaced - Enable interlaced encoding support, this can decrease encoding speed by up to 2%
+media-video/xine-ui:vdr - Enables Video Disk Recorder support
+net-analyzer/2ping:server - Install the server init scripts.
+net-analyzer/argus:libtirpc - Build against net-libs/libtirpc for RPC support
+net-analyzer/argus-clients:ft - Enable support for flow packets through net-analyzer/flow-tools
+net-analyzer/barnyard:sguil - Enable sguil (The Analyst Console for Network Security Monitoring) support
+net-analyzer/barnyard2:gre - Enable GRE support
+net-analyzer/barnyard2:mpls - Enable support for mpls networks
+net-analyzer/bro:broccoli - Enable the Bro Client Communication Library
+net-analyzer/bro:broctl - An interactive shell for managing Bro installations
+net-analyzer/bro:broker - Bro's new Messaging Library (experimental)
+net-analyzer/bro:geoip - Enable support for Maxmind's GeoIP library
+net-analyzer/bro:ipv6 - Support for mobile IPv6
+net-analyzer/bro:jemalloc - Support for the Jemalloc allocator
+net-analyzer/bro:python - Enable Python bindings
+net-analyzer/bro:ruby - Enable Ruby bindings (deprecated)
+net-analyzer/bro:tcmalloc - Enable Google's Performance Analysis Tools
+net-analyzer/bro:tools - Small auxiliary tools for Bro
+net-analyzer/bwm-ng:csv - Enable csv output
+net-analyzer/bwm-ng:html - Enable html output
+net-analyzer/cacti:doc - install html documentation
+net-analyzer/check_mk:agent-only - Install only the check_mk agent.
+net-analyzer/check_mk:apache_status - Install check_mk-agent apache-status plugin.
+net-analyzer/check_mk:dmi_sysinfo - Install check_mk-agent dmi_sysinfo plugin.
+net-analyzer/check_mk:livestatus - Enable livestatus.
+net-analyzer/check_mk:logwatch - Install check_mk-agent logwatch plugin.
+net-analyzer/check_mk:mysql - Install check_mk-agent mysql plugin.
+net-analyzer/check_mk:nagios4 - Depend on net-analyzer/nagios-core-4
+net-analyzer/check_mk:nfsexports - Install check_mk-agent nfsexports plugin.
+net-analyzer/check_mk:postgres - Install check_mk-agent postgres plugin.
+net-analyzer/check_mk:smart - Install check_mk-agent S.M.A.R.T plugin.
+net-analyzer/check_mk:wato - Enable check_mk WATO - check_mk's Web Administration Tool.
+net-analyzer/check_mk:zypper - Install check_mk-agent zypper plugin.
+net-analyzer/check_mk_agent:apache_status - Install check_mk-agent apache-status plugin.
+net-analyzer/check_mk_agent:logwatch - Install check_mk-agent logwatch plugin.
+net-analyzer/check_mk_agent:mysql - Install check_mk-agent mysql plugin.
+net-analyzer/check_mk_agent:nfsexports - Install check_mk-agent nfsexports plugin.
+net-analyzer/check_mk_agent:postgres - Install check_mk-agent postgres plugin.
+net-analyzer/check_mk_agent:smart - Install check_mk-agent S.M.A.R.T plugin.
+net-analyzer/check_mk_agent:zypper - Install check_mk-agent zypper plugin.
+net-analyzer/echoping:http - enable support for http protocol.
+net-analyzer/echoping:icp - enable support for ICP (used to monitor proxies).
+net-analyzer/echoping:priority - enable socket priority support.
+net-analyzer/echoping:smtp - enable support for SMTP protocol.
+net-analyzer/echoping:tos - enable support for TOS (TYpe Of Service).
+net-analyzer/ettercap:plugins - Install ettercap plugins (et_*.so)
+net-analyzer/flent:plots - Enable drawing plots
+net-analyzer/flowgrind:pcap - Enable packet capturing support using net-libs/libpcap
+net-analyzer/fprobe:messages - enable console messages
+net-analyzer/goaccess:btree - Enable Tokyo Cabinet's on-disk B+ Tree database backend
+net-analyzer/goaccess:geoipv2 - Enable support for GeoIP2 through dev-libs/libmaxminddb
+net-analyzer/goaccess:getline - Use GNU getline() to parse full line requests
+net-analyzer/goaccess:memhash - Enable Tokyo Cabinet's on-memory hash database backend
+net-analyzer/goaccess:tokyocabinet - Enable Tokyo Cabinet's on-memory hash database backend
+net-analyzer/gr-fosphor:glfw - enable GLFW based interface
+net-analyzer/graphite-web:carbon - Enable carbon support
+net-analyzer/graphite-web:memcached - Enable memcached support
+net-analyzer/hexinject:experimental - Install experimental packets.tcl
+net-analyzer/hexinject:tools - Install hex2raw and prettypacket tools
+net-analyzer/httping:tfo - Enable support for TCP Fast Open
+net-analyzer/hydra:ncp - NCP protocol (NetWare) support through net-fs/ncpfs
+net-analyzer/icinga:contrib - additional scripts
+net-analyzer/icinga:eventhandler - Adds support for running custom scripts whenever a host or service state change occurs
+net-analyzer/icinga:idoutils - Adds DB support
+net-analyzer/icinga:lighttpd - Adds Lighttpd support
+net-analyzer/icinga:plugins - Adds support for nagios plugins
+net-analyzer/icinga:web - Adds generic web interface support
+net-analyzer/icinga-web:pnp - Enables pnp4nagios integration
+net-analyzer/icinga2:classicui - Adds support for the old interface
+net-analyzer/icinga2:console - Adds support for line-editing in the console
+net-analyzer/icinga2:lto - Adds support for link time optimization
+net-analyzer/icinga2:mail - Allows for mailing of alerts
+net-analyzer/icinga2:nano-syntax - Adds support for syntax used in the nano editor
+net-analyzer/icinga2:plugins - Adds support for nagios plugins
+net-analyzer/icinga2:studio - Adds support for Icinga-studio
+net-analyzer/ipsumdump:nanotimestamp - Enable timestamps with nano-second resolution
+net-analyzer/linkchecker:sqlite - Mozilla Bookmark parsing
+net-analyzer/mate-netspeed:gtk3 - Build with GTK+3 instead of GTK+2
+net-analyzer/metasploit:development - Install dependencies needed for metasploit and exploit development
+net-analyzer/metasploit:nexpose - Enable the plugin to integrate with nexpose
+net-analyzer/metasploit:openvas - Enable the plugin to integrate net-analyzer/openvas
+net-analyzer/metasploit:oracle - Enable restricted oracle modules which have additional deps
+net-analyzer/metasploit:pcap - Enable libpcap for packet sniffing
+net-analyzer/mk-livestatus:nagios4 - Generate a net-analyzer/nagios-4 compatible plugin
+net-analyzer/monitoring-plugins:dns - Install net-dns/bind-tools required for monitoring DNS servers. Disabling the flag does not remove any plugins.
+net-analyzer/monitoring-plugins:fping - Install net-analyzer/fping required for fancy ping monitoring. Disabling the flag does not remove any plugins.
+net-analyzer/monitoring-plugins:game - Install games-util/qstat required for monitoring FPS servers. Disabling the flag does not remove any plugins.
+net-analyzer/monitoring-plugins:snmp - Install dev-perl/Net-SNMP and net-analyzer/net-snmp required for monitoring SNMP values. Disabling the flag does not remove any plugins.
+net-analyzer/monitoring-plugins:ssh - Install net-misc/openssh required for monitoring SSH servers. Disabling the flag does not remove any plugins.
+net-analyzer/munin:apache - Set up the configuration of the CGI generation of HTML and graphs to work with Apache. This also install an include-able configuration file.
+net-analyzer/munin:asterisk - Install the packages required for monitoring Asterisk. Disabling the flag does not remove any plugin files.
+net-analyzer/munin:cgi - Install the CGI-compatible scripts for on-the-fly generation of web pages and graphs. This is only meaningful if the minimal USE flag is disabled.
+net-analyzer/munin:dhcpd - Install dev-perl/Net-IP, dev-perl/HTTP-Date and net-misc/dhcp to monitor DHCP lease usage. This only works if the server is on the same system as the node, so the server is also brought in. Disabling the flag does not remove any plugin file.
+net-analyzer/munin:doc - Build and install a local copy of the HTML documentation for the whole software. This requires dev-python/sphinx to process the documentation sources.
+net-analyzer/munin:http - Install dev-perl/libwww-perl required for monitoring HTTP-based services such as Apache and nginx. Disabling the flag does not remove any plugin file.
+net-analyzer/munin:ipmi - Install sys-apps/ipmitool required for monitoring IPMI sensors. Disabling the flag does not remove any plugin file.
+net-analyzer/munin:ipv6 - Add support for IPv6 in munin-node. IPv6 support for the master is always enabled, but the node requires a newer version of dev-perl/Net-Server, capable of listening to IPv6 sockets.
+net-analyzer/munin:irc - Install the packages required for monitoring IRC. Disabling the flag does not remove any plugin files.
+net-analyzer/munin:java - Build the Java-based plugins to monitor JMX-compatible applications. Disabling the flag removes the jmx monitoring plugins.
+net-analyzer/munin:memcached - Install the packages required for memcached monitoring. Disabling the flag does not remove any plugin files.
+net-analyzer/munin:minimal - Only install munin-node and its plugins. This excludes the scripts to generate the web pages and the graphs.
+net-analyzer/munin:mysql - Install the packages required for monitoring MySQL. Disabling the flag does not remove any plugin files.
+net-analyzer/munin:postgres - Install the packages required for monitoring PostgreSQL. Disabling the flag does not remove any plugin files.
+net-analyzer/munin:syslog - Configure the node by default to log on syslog. This requires the presence of virtual/perl-Sys-Syslog. As of version 2.0.2, the master scripts only log to file, and not to syslog.
+net-analyzer/nagios-core:classicui - use the classic web theme
+net-analyzer/nagios-core:lighttpd - install www-servers/lighttpd config
+net-analyzer/nagios-core:web - enable web interface
+net-analyzer/nagios-plugin-check_raid:3ware - Support 3ware RAID controllers
+net-analyzer/nagios-plugin-check_raid:aacraid - Support Adaptec AAC-RAID controllers
+net-analyzer/nagios-plugin-check_raid:dmraid - Support Device-Mapper RAID
+net-analyzer/nagios-plugin-check_raid:hpa - Support HP Array controllers
+net-analyzer/nagios-plugin-check_raid:hpsa - Support HP SmartArray (CCISS) controllers
+net-analyzer/nagios-plugin-check_raid:i2o - Support DPT-I2O controllers (mostly Adaptec)
+net-analyzer/nagios-plugin-check_raid:megaraid-sas - Support LSI MegaRAID SAS controllers
+net-analyzer/nagios-plugin-check_raid:megaraid-scsi - Support LSI MegaRAID SCSI controllers
+net-analyzer/nagios-plugin-check_raid:mpt - Support LSI MPT Fusion controllers
+net-analyzer/nagios-plugin-check_raid:mpt-sas2 - Support LSI SAS-2 controllers
+net-analyzer/nagios-plugins:nagios-dns - Install net-dns/bind-tools required for monitoring DNS servers. Disabling the flag does not remove any plugin file.
+net-analyzer/nagios-plugins:nagios-game - Install games-util/qstat required for monitoring FPS servers. Disabling the flag does not remove any plugin file.
+net-analyzer/nagios-plugins:nagios-ping - Install net-analyzer/fping required for fancy ping monitoring. Disabling the flag does not remove any plugin file.
+net-analyzer/nagios-plugins:snmp - Install dev-perl/Net-SNMP required for monitoring SNMP values. Disabling the flag does not remove any plugin file.
+net-analyzer/nagios-plugins:ssh - Install net-misc/openssh required for monitoring SSH servers. Disabling the flag does not remove any plugin file.
+net-analyzer/nagios-plugins-flameeyes:smart - Install sys-apps/smartmontools required for S.M.A.R.T. disk monitoring. Disabling the flag removes the plugin file. This plugin also requires the sudo flag to be enable.
+net-analyzer/nagvis:automap - Enable automated map generation using media-gfx/graphviz
+net-analyzer/net-snmp:elf - Enable the use of elf utils to check uptime on some systems
+net-analyzer/net-snmp:mfd-rewrites - Use MFD rewrites of mib modules where available
+net-analyzer/net-snmp:netlink - Use dev-libs/libnl to fetch TCP statistics instead of using /proc/net/tcp (Linux only).
+net-analyzer/net-snmp:pci - Use libpci (from sys-apps/pciutils) to look up network interface description. This feature is only available on Linux.
+net-analyzer/net-snmp:rpm - Enable monitoring of app-arch/rpm. This flag requires the bzip2 and zlib flags to be enabled as well.
+net-analyzer/net-snmp:smux - Enable support for the legacy smux protocol (superseded by agentx)
+net-analyzer/net-snmp:ucd-compat - Build UCD compatibility library. Increases significantly the install size.
+net-analyzer/netdata:compression - Enable compression via zlib
+net-analyzer/netdata:ipmi - Install sys-apps/ipmitool required for monitoring IPMI sensors.
+net-analyzer/netdata:nfacct - Enable the nfacct plugin
+net-analyzer/netdata:nodejs - Enable use of nodejs (which some plugins use)
+net-analyzer/netperf:demo - Emit interim results during the run. May affect results
+net-analyzer/nfdump:compat15 - Enable read support for nfdump data files created with nfdump 1.5.x
+net-analyzer/nfdump:ftconv - Build the flow-tools to nfdump converter
+net-analyzer/nfdump:nfprofile - Build nfprofile used by NfSen
+net-analyzer/nfdump:nftrack - Build nfprofile used by PortTracker
+net-analyzer/nfdump:readpcap - Build nfcapd collector to read from pcap file instead ofnetwork data
+net-analyzer/nfdump:sflow - Build sflow collector sfcpad
+net-analyzer/nmap:libssh2 - Enable SSH support through net-libs/libssh2
+net-analyzer/nmap:ncat - Install the ncat utility
+net-analyzer/nmap:ndiff - Install the ndiff utility
+net-analyzer/nmap:nmap-update - Install nmap-update, which uses dev-vcs/subversion to update nmap scripts in your home directory
+net-analyzer/nmap:nping - Install the nping utility
+net-analyzer/nmap:nse - Include support for the Nmap Scripting Engine (NSE)
+net-analyzer/nmap:system-lua - Use dev-lang/lua instead of the bundled liblua
+net-analyzer/nmap:zenmap - Install the GTK+ based nmap GUI, zenmap
+net-analyzer/nrpe:command-args - Build support for specifying the command-line arguments from the Nagios/Icinga master. Make sure you understand the implications of this flag as it can be a security risk.
+net-analyzer/nrpe:minimal - Only build the check plugins for Nagios/Icinga, and not the daemon.
+net-analyzer/nsca:crypt - Build support for crypted communication with nsca, through dev-libs/libmcrypt. It's recommended not to disable this flag unless all the communication will be handled in an absolutely safe environment.
+net-analyzer/nsca:minimal - Only build and install the send_nsca command and not the daemon. This allows a very minimal install with no overhead when setting up a node.
+net-analyzer/openvas:pdf - Enable pdf report creation
+net-analyzer/pchar:pcap - Use the net-libs/libpcap library
+net-analyzer/pinger:gtk2 - Install the gtkpinger GUI utility based on x11-libs/gtk+:2
+net-analyzer/pinger:gtk3 - Install the gtkpinger GUI utility based on x11-libs/gtk+:3
+net-analyzer/pmacct:64bit - Use 64bit counters instead of 32bit ones
+net-analyzer/pmacct:geoipv2 - Enable support for GeoIP2 through dev-libs/libmaxminddb
+net-analyzer/pmacct:jansson - Enable support for JSON through dev-libs/jansson
+net-analyzer/pmacct:kafka - Enable support for Apache Kafka through dev-libs/librdkafka
+net-analyzer/pmacct:mongodb - Enable support for MongoDB through dev-libs/mongo-c-driver
+net-analyzer/pmacct:ndpi - Enable support for nDPI through net-libs/nDPI
+net-analyzer/pmacct:nflog - Enable support for NFLOG through uacctd
+net-analyzer/pmacct:rabbitmq - Enable support for RabbitMQ through net-libs/rabbitmq-c
+net-analyzer/pmacct:ulog - Enable support for ULOG in older kernels (deprecated)
+net-analyzer/pmacct:zmq - Enable support for ZeroMQ through net-libs/zeromq
+net-analyzer/pnp4nagios:icinga - Build against net-analyzer/icinga2 or net-analyzer/icinga instead of net-analyzer/nagios-core
+net-analyzer/pnp4nagios:nagios - Build against net-analyzer/nagios-core (the default)
+net-analyzer/prelude-lml:tls - Enables Prelude LML support Syslog through TLS using net-libs/gnutls.
+net-analyzer/rrdcollect:exec - Enable exec:/// support
+net-analyzer/rrdcollect:librrd - Use the librrd library from net-analyzer/rrdtool
+net-analyzer/rrdtool:graph - Enable support for graphing functions
+net-analyzer/rrdtool:rados - Enable support for librados from sys-cluster/ceph
+net-analyzer/rrdtool:rrdcgi - Build rrdcgi support
+net-analyzer/sancp:sguil - Enable sguil (The Analyst Console for Network Security Monitoring) support
+net-analyzer/sarg:gd - Enable support for graphs in reports through media-libs/gd
+net-analyzer/sarg:pcre - Enable support for regular expressions in the hostalias file through dev-libs/libpcre
+net-analyzer/scanlogd:nids - Use net-libs/libnids for packet capturing
+net-analyzer/scanlogd:pcap - Use net-libs/libpcap for packet capturing
+net-analyzer/scapy:pyx - Enable dev-python/pyx support for psdump/pdfdump commands
+net-analyzer/scapy:tcpreplay - Enable net-analyzer/tcpreplay support for fast packet replay
+net-analyzer/scapy:visual - Enable dev-python/visual support for 3d graphs
+net-analyzer/smokeping:dig - Install net-dns/bind-tools for dig functionality
+net-analyzer/smokeping:echoping - Install net-analyzer/echoping for echoping functionality
+net-analyzer/smokeping:ssh - Install ssh functionality
+net-analyzer/smokeping:telnet - Install dev-perl/Net-Telnet for telnet functionality
+net-analyzer/sngrep:eep - Enable EEP packet send/receive support
+net-analyzer/sngrep:gnutls - Use net-libs/gnutls to parse captured TLS packets
+net-analyzer/sngrep:openssl - Use dev-libs/openssl to parse captured TLS packets
+net-analyzer/snort:active-response - Enables support for automatically sending TCP resets and ICMP unreachable messages to terminate connections. Used with inline deployments.
+net-analyzer/snort:control-socket - Enables Snort's control socket.
+net-analyzer/snort:dynamicplugin - Enable ability to dynamically load preprocessors, detection engine, and rules library. This is required if you want to use shared object (SO) snort rules.
+net-analyzer/snort:file-inspect - Enables extended file inspection capabilities.
+net-analyzer/snort:flexresp3 - Enables support for new flexable response preprocessor for enabling connection tearing for inline deployments. Replaces flexresp and flexresp2.
+net-analyzer/snort:gre - Enable support for inspecting and processing Generic Routing Encapsulation (GRE) packet headders. Only needed if you are monitoring GRE tunnels.
+net-analyzer/snort:high-availability - Enables high-availability state sharing.
+net-analyzer/snort:inline-init-failopen - Enables support to allow traffic to pass (fail-open) through inline deployments while snort is starting and not ready to begin inspecting traffic. If this option is not enabled, network traffic will not pass (fail-closed) until snort has fully started and is ready to perform packet inspection.
+net-analyzer/snort:large-pcap-64bit - Allows Snort to read pcap files that are larger than 2 GB. ONLY VALID FOR 64bit SYSTEMS!
+net-analyzer/snort:libtirpc - Build against net-libs/libtirpc for RPC support
+net-analyzer/snort:linux-smp-stats - Enable accurate statistics reporting through /proc on systems with multipule processors.
+net-analyzer/snort:mpls - Enables support for processing and inspecting Multiprotocol Label Switching MPLS network network traffic. Only needed if you are monitoring an MPLS network.
+net-analyzer/snort:non-ether-decoders - Enable decoding of non-ethernet protocols such as TokenRing, FDDI, IPX, etc.
+net-analyzer/snort:normalizer - Enables support for normalizing packets in inline deployments to help minimize the chances of detection evasion.
+net-analyzer/snort:paf - Enables support for Protocol Aware Flushing. This allows Snort to statefully scan a stream and reassemble a complete protocol data unit regardless of segmentation.
+net-analyzer/snort:perfprofiling - Enables support for preprocessor and rule performance profiling using the perfmonitor preprocessor.
+net-analyzer/snort:ppm - Enables support for setting per rule or per packet latency limits. Helps protect against introducing network latency with inline deployments.
+net-analyzer/snort:react - Enables support for the react rule keyword. Supports interception, termination, and redirection of HTTP connections.
+net-analyzer/snort:reload-error-restart - Enables support for completely restarting snort if an error is detected durring a reload.
+net-analyzer/snort:shared-rep - Enables the use of shared memory for the Reputation Preprocessor (Only available on Linux systems)
+net-analyzer/snort:side-channel - Enables Snort's the side channel.
+net-analyzer/snort:sourcefire - Enables Sourcefire specific build options, which include --enable-perfprofiling and --enable-ppm.
+net-analyzer/snort:targetbased - Enables support in snort for using a host attibute XML file (attribute_table.dtd). This file needs to be created by the user and should define the IP address, operating system, and services for all hosts on the monitored network. This is cumbersome, but can improve intrusion detection accuracy.
+net-analyzer/snort:zlib - Enables HTTP inspection of compressed web traffic. Requires dynamicplugin be enabled.
+net-analyzer/suricata:af-packet - Enable AF_PACKET support
+net-analyzer/suricata:control-socket - Enable unix socket
+net-analyzer/suricata:cuda - Enable NVIDIA Cuda computations support
+net-analyzer/suricata:detection - Enable detection modules
+net-analyzer/suricata:logrotate - Install logrotate rule
+net-analyzer/suricata:luajit - Enable Luajit support
+net-analyzer/suricata:nflog - Enable libnetfilter_log support
+net-analyzer/suricata:nfqueue - Enable NFQUEUE support for inline IDP
+net-analyzer/suricata:redis - Enable Redis support
+net-analyzer/suricata:rules - Install default ruleset
+net-analyzer/symon:perl - Enables a generic perl symux client
+net-analyzer/symon:symon - Enables the system monitor. Offers no functionality but monitoring and forwarding of measured data
+net-analyzer/symon:symux - Enables the multiplexer which stores incoming symon streams on disk in RRD (net-analyzer/rrdtool) files
+net-analyzer/tcpdump:drop-root - Drop privileges to tcpdump:tcpdump when run as root
+net-analyzer/tcpdump:smi - Build with net-libs/libsmi to load MIBs on the fly to decode SNMP packets
+net-analyzer/tcpreplay:pcapnav - Enable if you want the jump to byte offset feature via net-libs/libpcapnav
+net-analyzer/tcpreplay:tcpdump - Use net-analyzer/tcpdump for packet decoding feature
+net-analyzer/testssl:bundled-openssl - Install precompiled versions of OpenSSL for greater testing coverage
+net-analyzer/wapiti:kerberos - Support Kerberos authentication
+net-analyzer/wapiti:ntlm - Support NTLM authentication
+net-analyzer/wireshark:adns - Use net-dns/c-ares to resolve DNS names
+net-analyzer/wireshark:androiddump - Install androiddump, an extcap interface to capture from Android devices
+net-analyzer/wireshark:bcg729 - Use media-plugins/mediastreamer-bcg729 to play G.729 codec
+net-analyzer/wireshark:capinfos - Install capinfos, to print information about capture files
+net-analyzer/wireshark:captype - Install captype, to print the file types of capture files
+net-analyzer/wireshark:ciscodump - Install ciscodump, extcap interface to capture from a remote Cisco router
+net-analyzer/wireshark:crypt - Use dev-libs/libgcrypt to decrypt traffic
+net-analyzer/wireshark:dftest - Install dftest, to display filter byte-code, for debugging dfilter routines
+net-analyzer/wireshark:doc-pdf - Build documentation in pdf format (US and a4 paper sizes)
+net-analyzer/wireshark:dumpcap - Install dumpcap, to dump network traffic from inside wireshark
+net-analyzer/wireshark:editcap - Install editcap, to edit and/or translate the format of capture files
+net-analyzer/wireshark:libssh - Use net-libs/libssh (for sshdump)
+net-analyzer/wireshark:libxml2 - Use dev-libs/libxml2 for handling XML configuration in dissectors
+net-analyzer/wireshark:lz4 - Use app-arch/lz4 for compression/decompression
+net-analyzer/wireshark:mergecap - Install mergecap, to merge two or more capture files into one
+net-analyzer/wireshark:netlink - Use dev-libs/libnl
+net-analyzer/wireshark:nghttp2 - Use net-libs/nghttp2 for HTTP/2 support
+net-analyzer/wireshark:pcap - Use net-libs/libpcap for network packet capturing (build dumpcap, rawshark)
+net-analyzer/wireshark:randpkt - Install randpkt, a utility for creating pcap trace files full of random packets
+net-analyzer/wireshark:randpktdump - Install randpktdump, an extcap interface to provide access to the random packet generator (randpkt)
+net-analyzer/wireshark:reordercap - Install reordercap, to reorder input file by timestamp into output file
+net-analyzer/wireshark:sbc - Use media-libs/sbc for playing back SBC encoded packets
+net-analyzer/wireshark:sharkd - Install sharkd, the daemon variant of wireshark
+net-analyzer/wireshark:smi - Use net-libs/libsmi to resolve numeric OIDs into human readable format
+net-analyzer/wireshark:snappy - Use app-arch/snappy for snappy compression and decompression
+net-analyzer/wireshark:spandsp - Use media-libs/spandsp for for G.722 and G.726 codec support in the RTP Player
+net-analyzer/wireshark:sshdump - Install sshdump, an extcap interface to capture from a remote host through SSH
+net-analyzer/wireshark:text2pcap - Install text2pcap, to generate a capture file from an ASCII hexdump of packets
+net-analyzer/wireshark:tfshark - Install tfshark, a terminal-based version of the FileShark capability
+net-analyzer/wireshark:tshark - Install tshark, to dump and analyzer network traffic from the command line
+net-analyzer/wireshark:udpdump - Install udpdump, to get packets exported from a source (like a network device or a GSMTAP producer) that are dumped to a pcap file
+net-analyzer/zabbix:agent - Enable zabbix agent (for to-be-monitored machines)
+net-analyzer/zabbix:frontend - Enable zabbix web frontend
+net-analyzer/zabbix:ipv6 - Turn on support of IPv6
+net-analyzer/zabbix:java - Enable Zabbix Java JMX Management Gateway
+net-analyzer/zabbix:libxml2 - Use libxml2 client library
+net-analyzer/zabbix:odbc - Enable Database Monitor and use UnixODBC Library by default
+net-analyzer/zabbix:openipmi - Enable openipmi things
+net-analyzer/zabbix:proxy - Enable proxy support
+net-analyzer/zabbix:server - Enable zabbix server
+net-analyzer/zabbix:ssh - SSH v2 based checks
+net-analyzer/zabbix:static - Build statically linked binaries
+net-analyzer/zmap:json - Add support to store results JSON based
+net-analyzer/zmap:mongo - Add support for storing in a mongo DB via dev-db/mongodb
+net-analyzer/zmap:redis - Add support for storing in a redis DB via dev-libs/hiredis
+net-dialup/accel-ppp:ipoe - Build IPoE kernel module
+net-dialup/accel-ppp:shaper - Support for traffic shaping
+net-dialup/accel-ppp:valgrind - Compile in valgrind hints
+net-dialup/freeradius:pcap - Build the RADIUS sniffer which requires net-libs/libpcap.
+net-dialup/freeradius-client:scp - Add service type hints derived from username prefix
+net-dialup/freeradius-client:shadow - Enable shadow password support
+net-dialup/mgetty:fax - Enables fax support
+net-dialup/mgetty:fidonet - Enables FidoNet support
+net-dialup/ppp:activefilter - Enables active filter support
+net-dialup/ppp:atm - Enables ATM (Asynchronous Transfer Mode) protocol support
+net-dialup/ppp:dhcp - Installs PPP DHCP client plugin for IP address allocation by a DHCP server (see http://www.netservers.co.uk/gpl/)
+net-dialup/ppp:eap-tls - Enables support for Extensible Authentication Protocol and Transport Level Security (see http://www.nikhef.nl/~janjust/ppp/index.html)
+net-dialup/ppp:gtk - Installs GTK+ password prompting program that can be used by passprompt.so PPP plugin for reading the password from a X11 input terminal
+net-dialup/ppp:ipv6 - Enables support for IP version 6
+net-dialup/ppp:pam - Enables PAM (Pluggable Authentication Modules) support
+net-dialup/ppp:radius - Enables RADIUS support
+net-dialup/xl2tpd:dnsretry - Patch for host lookup retries, activated by redial feature
+net-dialup/xl2tpd:kernel - Enable kernel interface for PPPoL2TP
+net-dns/avahi:autoipd - Build and install the IPv4LL (RFC3927) network address configuration daemon
+net-dns/avahi:bookmarks - Install the avahi-bookmarks application (requires dev-python/twisted-core and dev-python/twisted-web)
+net-dns/avahi:gtk3 - Build the avahi-ui-gtk3 library, and use gtk3 for the avahi utilities under USE=utils
+net-dns/avahi:howl-compat - Enable compat libraries for howl
+net-dns/avahi:mdnsresponder-compat - Enable compat libraries for mDNSResponder
+net-dns/avahi:utils - Install the avahi gtk+ utils avahi-discover, bssh, and bvnc
+net-dns/bind:dlz - Enables dynamic loaded zones, 3rd party extension
+net-dns/bind:dnstap - Enables dnstap packet logging
+net-dns/bind:filter-aaaa - Enable filtering of AAAA records over IPv4
+net-dns/bind:fixed-rrset - Enables fixed rrset-order option
+net-dns/bind:gost - Enables gost OpenSSL engine support
+net-dns/bind:gssapi - Enable gssapi support
+net-dns/bind:json - Enable JSON statistics channel
+net-dns/bind:lmdb - Enable LMDB support to store configuration for 'addzone' zones
+net-dns/bind:nslint - Build and install the nslint util
+net-dns/bind:rpz - Enable response policy rewriting (rpz)
+net-dns/bind:urandom - Use /dev/urandom instead of /dev/random
+net-dns/bind-tools:gost - Enables gost OpenSSL engine support
+net-dns/bind-tools:gssapi - Enable gssapi support
+net-dns/bind-tools:urandom - Use /dev/urandom instead of /dev/random
+net-dns/ddclient:cloudflare - Enable support for updating IP address via CloudFlare
+net-dns/ddclient:hardened - Use iproute2 instead of ifconfig to grab an IP address
+net-dns/dnscrypt-proxy:plugins - Enable plugin support to inspect and modify queries and responses
+net-dns/dnscrypt-proxy:systemd - Use systemd's socket activation instead of creating the sockets itself
+net-dns/dnsdist:dnscrypt - Enable the ability to act as a DNSCrypt server
+net-dns/dnsdist:luajit - Use dev-lang/luajit instead of dev-lang/lua
+net-dns/dnsdist:regex - Enable support for regular expression matching via dev-libs/re2
+net-dns/dnsdist:remote-logging - Enable support for remote logging via dev-libs/protobuf
+net-dns/dnsdist:ssl - Enable support for and encrypted client-server communication via dev-libs/libsodium
+net-dns/dnsmasq:auth-dns - Add support for acting as an authorative DNS server.
+net-dns/dnsmasq:conntrack - Add support for Linux conntrack connection marking.
+net-dns/dnsmasq:dhcp - Enable support for acting as a DHCP server.
+net-dns/dnsmasq:dhcp-tools - Install extra command line tools for manually managing DHCP leases.
+net-dns/dnsmasq:dnssec - Enable support DNSSEC validation and caching.
+net-dns/dnsmasq:id - Whether report *.bind CHAOS info to clients, otherwise forward such requests upstream instead
+net-dns/dnsmasq:libidn2 - Enable support for Internationalized Domain Names, via net-dns/libidn2 rather than net-dns/libidn
+net-dns/dnsmasq:script - Enable support for calling scripts when leases change.
+net-dns/dnsmasq:tftp - Enables built in TFTP server for netbooting.
+net-dns/dnssec-validator:ecdsa-check - Requires openssl[-bindist]
+net-dns/hash-slinger:ipsec - Enable support for IPSECKEY records (ipseckey)
+net-dns/hash-slinger:openpgp - Enable support for OPENPGPKEY records (openpgpkey)
+net-dns/hash-slinger:ssh - Enable support for SSHFP records (sshfp)
+net-dns/idnkit:liteonly - Compile and install lite library only
+net-dns/knot:dnsproxy - Enable the tiny DNS proxy module
+net-dns/knot:dnstap - Include support for the dnstap binary log format (http://dnstap.info/)
+net-dns/knot:fastparser - Use a zone file parser that is faster, but requires more memory and CPU time to compile
+net-dns/knot:libidn2 - If IDN support is enabled, use net-dns/libidn2 instead of net-dns/libidn
+net-dns/knot:noudp - Enable the module which can send empty truncated responses to UDP queries
+net-dns/knot:onlinesign - Enable the module that sign zones on the fly instead of pre-signing zone
+net-dns/knot:rosedb - Enable the module that staticaly override certain responses
+net-dns/knot:rrl - Enable the response rate limiting module
+net-dns/knot:stats - Enable the server statistics module
+net-dns/knot:synthrecord - Enable the automatic forward/reverse records module
+net-dns/knot:utils - Install Knot utilities, such as kdig, kzonecheck, ...
+net-dns/knot:whoami - Enable the whoami response module
+net-dns/ldns-utils:dane - Enable DNS-based Authentication of Named Entities (DANE) support
+net-dns/ldns-utils:ecdsa - Enable ECDSA support
+net-dns/ldns-utils:gost - Enable GOST support
+net-dns/maradns:authonly - Allows one to build only authoritative DNS server
+net-dns/mydns:alias - Enable David Phillips aliasing
+net-dns/mydns:status - Enable the STATUS opcode to check server status
+net-dns/nsd:bind8-stats - Enables BIND8 like NSTATS and XSTATS
+net-dns/nsd:libevent - Use libevent or libev, useful when zone count is high
+net-dns/nsd:minimal-responses - If minimal responses are disabled, responses are more likely to get truncated, resulting in TCP fallback
+net-dns/nsd:munin - Install a plugin for net-analyzer/munin to graph statistical data from nsd.
+net-dns/nsd:nsec3 - Enable NSEC3 support
+net-dns/nsd:ratelimit - Enables ratelimiting, based on query name, type and source
+net-dns/nsd:root-server - Configure NSD as a root server
+net-dns/nsd:runtime-checks - Enable runtime checks, this could lead to a reduced service level
+net-dns/opendnssec:auditor - Enables auditing capabilities for OpenDNSSEC
+net-dns/opendnssec:eppclient - Enables support for automatic submission of DNSSEC keys to an upstream epp server
+net-dns/opendnssec:external-hsm - Enables support for storing DNSSEC keys through an arbitrary non-portage PKCS#11 interface, specified through an environment variable
+net-dns/opendnssec:opensc - Enables support for storing DNSSEC keys through a dev-libs/opensc PKCS#11 interface
+net-dns/opendnssec:signer - Enables signing capabilities for OpenDNSSEC
+net-dns/opendnssec:softhsm - Enables support for storing DNSSEC keys in a dev-libs/softhsm PKCS#11 object
+net-dns/pdns:botan - Make it possible to use the dev-libs/botan library for crypto-related stuff (like DNSSec) which can be significantly faster than PolarSSL.
+net-dns/pdns:luajit - Enable support for dev-lang/luajit
+net-dns/pdns:mydns - Making it possible to use a MyDNS MySQL database with PowerDNS (not recommended for new deployments).
+net-dns/pdns:opendbx - Use a database supported by dev-db/opendbx as backend.
+net-dns/pdns:protobuf - Enable support for dev-libs/protobuf.
+net-dns/pdns:remote - Use a generic socket or pipe as a backend (via JSON RPC requests).
+net-dns/pdns:sodium - Use dev-libs/libsodium for cryptography
+net-dns/pdns:tinydns - Use a TinyDNS CDB database as backend.
+net-dns/pdns:tools - Build optional tools (dnsscan, dnsscope, etc..).
+net-dns/pdns-recursor:luajit - Enable support for dev-lang/luajit.
+net-dns/pdns-recursor:protobuf - Enable support for dev-libs/protobuf.
+net-dns/pdns-recursor:sodium - Use dev-libs/libsodium for cryptography
+net-dns/pdnsd:isdn - Linux-only: check status of ippp interfaces with ISDN-specific system calls.
+net-dns/pdnsd:urandom - Linux-only: use /dev/urandom (pseudo-random number generation) instead of the default use of random() PRNG.
+net-dns/resolvconf-symlink:symlink - Actually replace /etc/resolv.conf with a symlink. Without this flag, the ebuild is a no-op.
+net-dns/unbound:dnscrypt - Enable DNSCrypt support
+net-dns/unbound:dnstap - Enable dnstap support
+net-dns/unbound:ecdsa - Enable ECDSA support
+net-dns/unbound:gost - Enable GOST support
+net-firewall/arno-iptables-firewall:plugins - Install optional plugins
+net-firewall/conntrack-tools:libtirpc - Build against net-libs/libtirpc for RPC support
+net-firewall/ebtables:perl - Install the ebtables-save script which uses perl
+net-firewall/firehol:ipset - Use net-firewall/ipset.
+net-firewall/firewalld:gui - Builds and installs GUI configurator and GTK+ applet
+net-firewall/fwknop:client - Build fwknop client
+net-firewall/fwknop:extras - Install utility scripts and AppArmor policy for fwknopd
+net-firewall/fwknop:firewalld - Use net-firewall/firewalld as the default server backend
+net-firewall/fwknop:gdbm - Use sys-libs/gdbm to store fwknopd digest cache
+net-firewall/fwknop:gpg - Enable GPG support via app-crypt/gpgme
+net-firewall/fwknop:iptables - Use net-firewall/iptables as the default server backend
+net-firewall/fwknop:nfqueue - Enable UDP-only NFQUEUE server mode (no net-libs/libpcap dependency)
+net-firewall/fwknop:server - Build fwknopd server
+net-firewall/fwknop:udp-server - Enable UDP-only server mode (no net-libs/libpcap dependency)
+net-firewall/ipt_netflow:natevents - Netflow NAT translation events (NEL) support
+net-firewall/iptables:conntrack - Build against net-libs/libnetfilter_conntrack when enables the connlabel matcher
+net-firewall/iptables:netlink - Build against libnfnetlink which enables the nfnl_osf util
+net-firewall/iptables:nftables - Support nftables kernel interface
+net-firewall/iptables:pcap - Build against net-libs/libpcap which enables the nfbpf_compile util
+net-firewall/nufw:nfconntrack - Use netfilter_conntrack
+net-firewall/nufw:nfqueue - Use NFQUEUE instead of QUEUE
+net-firewall/nufw:pam_nuauth - Add support for pam nufw from PAM
+net-firewall/nufw:plaintext - Add support for authentication with plaintext files
+net-firewall/pftop:altq - Enable altq(4) support — alternate queuing of network packets.
+net-firewall/pglinux:cron - Install cron script
+net-firewall/pglinux:logrotate - Install logrotate.d file
+net-firewall/shorewall:init - Adds the capability to place the firewall in a safe state prior to bringing up the network interfaces
+net-firewall/shorewall:ipv4 - Installs everything needed to create a full IPv4 firewall
+net-firewall/shorewall:ipv6 - Adds the capability to create a full IPv6 firewall (requires net-firewall/shorewall ipv4 USE flag)
+net-firewall/shorewall:lite4 - Installs everything needed to just *run* an IPv4 compiled firewall script created with net-firewall/shorewall ipv4 USE flag
+net-firewall/shorewall:lite6 - Installs everything needed to just *run* an IPv6 compiled firewall script created with net-firewall/shorewall ipv6 USE flag
+net-firewall/ufw-frontends:kde - Use kdesu to gain root privileges (note: the flag has lower priority than "policykit")
+net-firewall/ufw-frontends:policykit - Use pkexec to gain root privileges
+net-fs/autofs:dmalloc - Enable debugging with the dmalloc library
+net-fs/autofs:ldap - Install LDAP module
+net-fs/autofs:libtirpc - Use TiRPC library instead of SunRPC
+net-fs/autofs:mount-locking - Enable locking to prevent corruption of /etc/mtab in the presence of concurrent auto-mounting. If enabled, recursive auto-mounting (eg. using autofs to bind or loop mount a filesystem which is itself auto-mounted) is not possible.
+net-fs/autofs:sasl - Enable SASL support in the LDAP module
+net-fs/cifs-utils:ads - Enable Active Directory support and create cifs.idmap binary - idmap support
+net-fs/cifs-utils:caps - libcap support
+net-fs/cifs-utils:caps-ng - libcap-ng support
+net-fs/cifs-utils:creds - cifs credentials support
+net-fs/cvmfs:aufs - Use AUFS instead of OverlayFS for the server
+net-fs/cvmfs:preload - Install the cvmfs cache preloader for distributed file systems
+net-fs/cvmfs:server - Install the cvmfsd program and init script
+net-fs/cvmfs:test-programs - Install unit test programs
+net-fs/netatalk:pgp - Add support pgp authentication module
+net-fs/netatalk:quota - Add support for user quota on various filesystems
+net-fs/netatalk:shadow - Add shadow support
+net-fs/netatalk:ssl - Use dev-libs/openssl to provide DHX User Access Modules. These are not used with most recent versions of OS X and can be kept disabled without risks.
+net-fs/netatalk:tracker - Add support for spotlight like tracker
+net-fs/netatalk:utils - Install afpstats script
+net-fs/nfs-utils:ldap - Add ldap support
+net-fs/nfs-utils:libmount - Link mount.nfs with libmount
+net-fs/nfs-utils:nfsdcld - Enable nfsdcld NFSv4 clientid tracking daemon
+net-fs/nfs-utils:nfsidmap - Enable support for newer nfsidmap helper
+net-fs/nfs-utils:nfsv4 - Enable support for NFSv4
+net-fs/nfs-utils:nfsv41 - Enable support for NFSv4.1
+net-fs/nfs-utils:uuid - Support UUID lookups in rpc.mountd
+net-fs/openafs:bitmap-later - Enable fast startup of file server by not reading bitmap till needed.
+net-fs/openafs:fuse - Build fuse client.
+net-fs/openafs:modules - Build libafs kernel module. Disable only if you know what you're doing: without this module OpenAFS client will not work.
+net-fs/openafs:pthreaded-ubik - Enable installation of pthreaded ubik applications.
+net-fs/openafs:supergroups - Enable support for nested pts groups.
+net-fs/s3fs:gnutls - Enable net-libs/gnutls crypto backend
+net-fs/s3fs:nettle - Use dev-libs/nettle network functions with GnuTLS.
+net-fs/s3fs:nss - Enable dev-libs/nss crypto backend
+net-fs/s3fs:openssl - Enable dev-libs/openssl crypto backend
+net-fs/s3ql:contrib - Install additional contributed scripts
+net-fs/samba:addc - Enable Active Directory Domain Controller support
+net-fs/samba:addns - Enable AD DNS integration
+net-fs/samba:ads - Enable Active Directory support
+net-fs/samba:aio - Enable asynchronous IO support
+net-fs/samba:ceph - Enable support for Ceph distributed filesystem via sys-cluster/ceph
+net-fs/samba:client - Enables the client part
+net-fs/samba:cluster - Enable support for clustering
+net-fs/samba:dmapi - Enable support for DMAPI. This currently works only in combination with XFS.
+net-fs/samba:gpg - Use app-crypt/gpgme for AD DC
+net-fs/samba:iprint - Enabling iPrint technology by Novell
+net-fs/samba:quota - Enables support for user quotas
+net-fs/samba:system-heimdal - Use app-crypt/heimdal instead of bundled heimdal.
+net-fs/samba:system-mitkrb5 - Use app-crypt/mit-krb5 instead of app-crypt/heimdal.
+net-fs/samba:winbind - Enables support for the winbind auth daemon
+net-fs/smbnetfs:gnome - Use the gnome-base/gnome-keyring for password management.
+net-ftp/frox:transparent - Enable transparent proxying of data connections
+net-ftp/lftp:convert-mozilla-cookies - Install the convert-mozilla-cookies script and its run-time dependencies
+net-ftp/lftp:verify-file - Install the verify-file script and its run-time dependencies
+net-ftp/proftpd:authfile - Enable support for the auth-file module
+net-ftp/proftpd:ban - Enable support for the mod_ban module
+net-ftp/proftpd:case - Enable support for the mod_case module
+net-ftp/proftpd:copy - Enable support for the mod_copy module
+net-ftp/proftpd:ctrls - Enable support for the mod_ctrls and mod_ctrls_admin modules
+net-ftp/proftpd:deflate - Enable support for the mod_deflate module
+net-ftp/proftpd:diskuse - Enable support for the mod_diskuse module
+net-ftp/proftpd:dso - Enable support for the mod_dso module
+net-ftp/proftpd:dynmasq - Enable support for the mod_dynmasq module, for dynamically updating MasqueradeAddress for dyndns-like scenarios)
+net-ftp/proftpd:exec - Enable support for the mod_exec module. WARNING: this could be a security risk
+net-ftp/proftpd:ident - Enable support for the mod_ident module
+net-ftp/proftpd:ifsession - Enable support for the ifsession module
+net-ftp/proftpd:ifversion - Enable support for the mod_ifversion module
+net-ftp/proftpd:log_forensic - Enable support for the mod_log_forensic module, log only suspicious actions.
+net-ftp/proftpd:memcache - Enable support for the mod_memcache module, for using memcached servers
+net-ftp/proftpd:msg - Enable support for the mod_msg module, allows system users to send messages to connected clients via the ftpdctl program.
+net-ftp/proftpd:qos - Enable support for the mod_qos module
+net-ftp/proftpd:ratio - Enable support for the mod_ratio module
+net-ftp/proftpd:readme - Enable support for the mod_readme module
+net-ftp/proftpd:rewrite - Enable support for the rewrite module
+net-ftp/proftpd:sftp - Enable support for the mod_sftp module and optionally mod_sftp_sql and mod_sftp_pam if matching USE flags are enabled
+net-ftp/proftpd:shaper - Enable support for the mod_shaper module
+net-ftp/proftpd:sitemisc - Enable support for the sitemisc module
+net-ftp/proftpd:softquota - Enable support for the quotatab module
+net-ftp/proftpd:trace - Build with trace support. Should not be enabled on production servers
+net-ftp/proftpd:unique_id - Enable support for the mod_unique_id module, every connection gets unique ID.
+net-ftp/proftpd:vroot - Enable support for the virtual root module
+net-ftp/pure-ftpd:anondel - Permit anonymous to delete files
+net-ftp/pure-ftpd:anonperm - Permit anonymous to change file permissions
+net-ftp/pure-ftpd:anonren - Permit anonymous to rename files
+net-ftp/pure-ftpd:anonres - Permit anonymous to resume file transfers
+net-ftp/pure-ftpd:charconv - Enables charset conversion
+net-ftp/pure-ftpd:implicittls - Enable TLS on Port 990
+net-ftp/pure-ftpd:noiplog - Disables logging of IP addresses
+net-ftp/pure-ftpd:paranoidmsg - Display paranoid messages instead of normal ones
+net-ftp/pure-ftpd:resolveids - Resolve UIDs/GIDs
+net-ftp/pure-ftpd:sysquota - Enables system quota support (needs sys-fs/quota)
+net-ftp/pure-ftpd:vchroot - Enable support for virtual chroot (possible security risk)
+net-ftp/yafc:ssh - Build with SFTP support
+net-im/ayttm:irc - Enable Internet Relay Chat support
+net-im/ayttm:lj - Enable livejournal.com support
+net-im/ayttm:smtp - Adds support for sending messages via RFC2821 SMTP
+net-im/bitlbee:libevent - Use libevent for event handling
+net-im/bitlbee:nss - Use NSS for SSL support in MSN and Jabber
+net-im/bitlbee:otr - Enable support for encrypted conversations
+net-im/bitlbee:plugins - Enable support for plugins
+net-im/bitlbee:purple - Use libpurple instead of the built-in IM protocol support
+net-im/bitlbee:twitter - Enable Twitter protocol support
+net-im/choqok:attica - Build Open Collaboration Services plugin using dev-libs/libattica
+net-im/choqok:konqueror - Build Konqueror Choqok plugin
+net-im/choqok:telepathy - Enable support for the real-time communication framework telepathy
+net-im/climm:otr - Enable encrypted conversations
+net-im/corebird:glade - Install glade catalogs for corebird
+net-im/corebird:spellcheck - Support spell checking
+net-im/coturn:mongodb - Enable support for the mongodb database
+net-im/coturn:redis - Enable support for the redis database
+net-im/ejabberd:captcha - Support for CAPTCHA Forms (XEP-158) on registration
+net-im/ejabberd:full-xml - Use XML features in XMPP stream (ex: CDATA), requires XML compliant clients
+net-im/ejabberd:hipe - Compile natively with HiPE, not recommended
+net-im/ejabberd:mssql - Enable Microsoft SQL Server support (via ODBC) for data storage
+net-im/ejabberd:mysql - Enable MySQL support for data storage
+net-im/ejabberd:nls - Enable character set conversion for mod_irc
+net-im/ejabberd:odbc - Enable ODBC support to access data storage
+net-im/ejabberd:postgres - Enable PostgreSQL support for data storage
+net-im/ejabberd:redis - Enable Redis support for transient data
+net-im/ejabberd:riak - Enable support for Riak - distributed NoSQL key-value data store
+net-im/ejabberd:roster-gw - Turn on workaround for processing gateway subscriptions
+net-im/ejabberd:sqlite - Enable SQLite database support
+net-im/ejabberd:zlib - Enable Stream Compression (XEP-0138) using zlib
+net-im/ekg2:gadu - Enable Gadu-Gadu protocol support (requires net-libs/libgadu).
+net-im/ekg2:gif - GIF token support for Gadu-Gadu protocol.
+net-im/ekg2:gnutls - Enable SSL/TLS support through GnuTLS for the plugins supporting it. If 'ssl' is enabled too, GnuTLS will be preferred where possible (and OpenSSL will be used elsewhere).
+net-im/ekg2:gpg - Enable jabber message encryption through app-crypt/gpgme.
+net-im/ekg2:jpeg - JPEG token support for Gadu-Gadu protocol.
+net-im/ekg2:minimal - Disable building extra plugins with no additional deps.
+net-im/ekg2:openssl - Support encryption in sim plugin, using OpenSSL.
+net-im/ekg2:oracle - Support logging messages into Oracle database.
+net-im/ekg2:sqlite - Support logging messages into SQLite3 database.
+net-im/ekg2:ssl - Enable the complete SSL/TLS support through OpenSSL. This also enables the 'sim' plugin which relies on OpenSSL.
+net-im/empathy:gnome-online-accounts - Enable using net-libs/gnome-online-accounts for authorization (e.g. for Google Talk)
+net-im/empathy:map - Enable world map support through media-libs/libchamplain
+net-im/err:irc - Pull optional dependencies, needed for IRC backend
+net-im/err:plugins - Enable support for installing plugins with dev-vcs/git
+net-im/gajim:idle - Enable idle module
+net-im/gajim:srv - SRV capabilities
+net-im/gajim:xhtml - Enable XHTML support
+net-im/kadu:gadu - Enables Gadu communication protocol
+net-im/kadu:mpd - Enables Music Player Daemon support
+net-im/kadu:otr - Enable char encryption via OTR library
+net-im/kadu:phonon - Enables phonon audio plugin
+net-im/kadu:sdk - Install Kadu SDK (cmake module, API headers)
+net-im/kadu:speech - Enables speech module
+net-im/mcabber:aspell - Adds support for app-text/aspell spell checker.
+net-im/mcabber:otr - Enable encrypted conversations using Off-The-Records messaging
+net-im/pidgin:gadu - Enable Gadu Gadu protocol support
+net-im/pidgin:groupwise - Enable Novell Groupwise protocol support
+net-im/pidgin:gstreamer - Enables voice and video sessions
+net-im/pidgin:gtk - Builds Pidgin, the GTK+ interface
+net-im/pidgin:meanwhile - Enable meanwhile support for Sametime protocol
+net-im/pidgin:ncurses - Build finch, console interface
+net-im/pidgin:prediction - Enable Contact Availability Prediction plugin
+net-im/pidgin:python - Build libgnt (GLib Ncurses Toolkit used by finch) with python scripting support
+net-im/pidgin:silc - Enable SILC protocol support
+net-im/pidgin:xscreensaver - Use X screensaver protocol extension to monitor idle/active status based on mouse/keyboard events
+net-im/pidgin:zephyr - Enable Zephyr protocol support
+net-im/prosody:jit - Use LuaJIT instead of vanilla Lua
+net-im/prosody:libevent - Use libevent for event handling
+net-im/prosody:zlib - Support for compressing XMPP streams with mod_compression
+net-im/psi:aspell - Enable spellchecking using app-text/aspell
+net-im/psi:enchant - Enable spellchecking using app-text/enchant
+net-im/psi:extras - Enable Psi+ patcheset
+net-im/psi:hunspell - Enable spellchecking using app-text/hunspell
+net-im/psi:iconsets - Install additional iconsets, some of them has not clear licensing
+net-im/psi:sql - Enable psi-new-history extras patch
+net-im/psi:webengine - Use dev-qt/qtwebengine instead of dev-qt/qtwebkit
+net-im/psi:webkit - Enable themed, html-based chatlogs
+net-im/psi:whiteboarding - Enable experimental interactive SVG drawing
+net-im/pyicq-t:webinterface - Install dependencies needed for the web interface
+net-im/qtox:X - Adds support for X11
+net-im/qtox:gtk - Adds support for GTK and Status Notifier tray backends
+net-im/skypeforlinux:pax_kernel - Triggers a paxmarking of the main skype binary
+net-im/slack-bin:pax_kernel - Triggers a paxmarking of the binary
+net-im/telepathy-connection-managers:gadu - Enable Gadu Gadu protocol support.
+net-im/telepathy-connection-managers:irc - Enable Internet Relay Chat (IRC) support.
+net-im/telepathy-connection-managers:meanwhile - Enable meanwhile support for Sametime protocol.
+net-im/telepathy-connection-managers:sip - Enable SIP/SIMPLE messaging and calling.
+net-im/telepathy-connection-managers:sipe - Enable Sip Exchange Protocol.
+net-im/telepathy-connection-managers:steam - Enable Steam Chat support.
+net-im/telepathy-connection-managers:xmpp - Enable XMPP protocol handler (this is also Google Talk).
+net-im/telepathy-connection-managers:yahoo - Enable Yahoo! messaging support.
+net-im/telepathy-connection-managers:zeroconf - Enable Link-Local Messaging via the zeroconf or Bonjour protocol.
+net-im/tkabber:plugins - Enables installation the extra plugins
+net-im/toxic:audio - Enables audio calling
+net-im/toxic:notifications - Enables desktop notifications with libnotify, with sound support.
+net-im/toxic:qrcode - Enables QR code support
+net-im/toxic:video - Enables video calling
+net-im/vacuum:adiummessagestyle - Use UI styles created for Adium
+net-im/vacuum:annotations - Enable adding comments to the contacts in the roster
+net-im/vacuum:aspell - Select app-text/aspell spell checker backend
+net-im/vacuum:autostatus - Change the status in accordance with the time of inactivity
+net-im/vacuum:avatars - Enable assigning and displaying avatars
+net-im/vacuum:birthdayreminder - Reminds about birthdays of your friends
+net-im/vacuum:bitsofbinary - Allow other modules to receive or send a small amount of binary data in XMPP stanza
+net-im/vacuum:bookmarks - Enable creating bookmarks of the Jabber conferences and Web pages
+net-im/vacuum:captchaforms - Perform tests for humanity outside of Web browser
+net-im/vacuum:chatstates - Post user's activity to the chat
+net-im/vacuum:clientinfo - Enable sending and receiving peer's application version, local time and last activity info
+net-im/vacuum:commands - Enable performing special commands provided by various services
+net-im/vacuum:compress - Compress stream of messages
+net-im/vacuum:console - Enable inspecting a raw XML stream
+net-im/vacuum:dataforms - Allow other modules to process and display data forms intended for the user
+net-im/vacuum:datastreamsmanager - Enable initiating a custom data stream between two XMPP entities
+net-im/vacuum:emoticons - Enable using smiley images in messages
+net-im/vacuum:enchant - Select app-text/enchant spell checker backend
+net-im/vacuum:filemessagearchive - Allows to save the history of conversations to local files
+net-im/vacuum:filestreamsmanager - Enable transferring files between two XMPP entities
+net-im/vacuum:filetransfer - Enable sending files to peers
+net-im/vacuum:gateways - Simplify the interaction with gateways to other IM systems
+net-im/vacuum:hunspell - Select app-text/hunspell spell checker backend
+net-im/vacuum:inbandstreams - Enable initiating in-band data stream between two XMPP enitites
+net-im/vacuum:iqauth - Enable logging on Jabber servers withous SASL authentication support
+net-im/vacuum:jabbersearch - Enable searching contacts in Jabber networks
+net-im/vacuum:messagearchiver - Enable saving the communication history both locally and on the server
+net-im/vacuum:messagecarbons - Allows to keep all user IM clients engaged in a conversation
+net-im/vacuum:multiuserchat - Enable Jabber multi-user conferences
+net-im/vacuum:pepmanager - Allows other plugins to recieve and publish PEP events
+net-im/vacuum:privacylists - Enable blocking the undesirable contacts
+net-im/vacuum:privatestorage - Allow other modules to store arbitrary data on the server
+net-im/vacuum:recentcontacts - Displays a recently used contacts
+net-im/vacuum:registration - Enable creating accounts in Jabber services
+net-im/vacuum:remotecontrol - Allows to remotely control the client
+net-im/vacuum:rosteritemexchange - Allows to exchange contact list items
+net-im/vacuum:rostersearch - Allows to search for contacts in the roster
+net-im/vacuum:servermessagearchive - Allows to save the history of communications on the server
+net-im/vacuum:servicediscovery - Enable receiving information about Jabber entities
+net-im/vacuum:sessionnegotiation - Enable initiating the session between two entities with setting the rules for XMPP stanzas exchange
+net-im/vacuum:shortcutmanager - Allows to setup user defined shortcuts
+net-im/vacuum:socksstreams - Enable initiating SOCKS5 data streams between two XMPP entities
+net-im/vacuum:urlprocessor - Allows other plugins to load data from custom types of URLs
+net-im/vacuum:vcard - Enable obtaining peer's personal contact information
+net-im/vacuum:xmppuriqueries - Allow other plugins to handle XMPP URI queries
+net-irc/atheme-services:cracklib - Enable nickserv/cracklib module for enforcing strong account passwords
+net-irc/atheme-services:largenet - Enable support/tweaks for large networks
+net-irc/atheme-services:ldap - Enable ldap-backed authentication module
+net-irc/atheme-services:perl - Install a perl module which wraps around the services' XML-RPC interface
+net-irc/bip:freenode - Enables freenode-specific functionality. Currently that is only support for mute lists (MODE #channel +q).
+net-irc/bip:noctcp - Disable the automatic CTCP VERSION reply which is often exploited by malicious people to cause a DoS (reconnect due to flooding).
+net-irc/bip:oidentd - Enable oidentd support
+net-irc/epic5:archive - Use app-arch/libarchive to use zip and tar archives from scripts.
+net-irc/epic5:valgrind - Compile against dev-util/valgrind headers to improve memory-leak checking when running epic5 under valgrind.
+net-irc/hexchat:libcanberra - Enable sound event support using media-libs/libcanberra
+net-irc/hexchat:libproxy - Enable proxy support.
+net-irc/hexchat:plugin-checksum - Build Checksum plugin (needs plugins)
+net-irc/hexchat:plugin-fishlim - Build FiSHLiM plugin (needs plugins )
+net-irc/hexchat:plugin-sysinfo - Build SysInfo plugin (needs plugins)
+net-irc/hexchat:theme-manager - Build the theme manager (mono)
+net-irc/inspircd:geoip - Add geoip support for country and city lookup based on IPs
+net-irc/inspircd:gnutls - Enable TLS support
+net-irc/inspircd:ipv6 - Enable support for IP version 6
+net-irc/inspircd:ldap - Enable LDAP support
+net-irc/inspircd:mysql - Enable MySQL database backend
+net-irc/inspircd:pcre - Adds support for Perl Compatible Regular Expressions
+net-irc/inspircd:posix - Adds support for POSIX-compatible functions
+net-irc/inspircd:postgres - Enable PostgreSQL database backend
+net-irc/inspircd:sqlite - Enable Sqlite database backend
+net-irc/inspircd:ssl - Enable SSL support
+net-irc/inspircd:tre - Enable support for TRE, a lightweight, robust, and efficient POSIX compliant regexp matching library
+net-irc/iroffer-dinoex:admin - Compile with HTTP Admin
+net-irc/iroffer-dinoex:blowfish - Compile with blowfish encryption support
+net-irc/iroffer-dinoex:chroot - Compile with chroot support
+net-irc/iroffer-dinoex:http - Compile with HTTP server support
+net-irc/iroffer-dinoex:kqueue - Compile with kqueue() support
+net-irc/iroffer-dinoex:memsave - Compile with memory protection
+net-irc/iroffer-dinoex:telnet - Compile with Telnet server support
+net-irc/irssi:proxy - Adds support for a loadable IRC proxy module
+net-irc/kvirc:dcc_video - Support video connections over DCC protocol
+net-irc/kvirc:phonon - Support Phonon for audio output
+net-irc/limnoria:crypt - Enables user authentication with GPG
+net-irc/ngircd:ident - Enables support for net-libs/libident
+net-irc/psybnc:multinetwork - Adds support for multiple networks
+net-irc/psybnc:oidentd - Adds support for oidentd
+net-irc/psybnc:scripting - Adds scripting support
+net-irc/quassel:X - Build the Qt5 GUI client for quassel. If this USE flag is disabled, the GUI is not built, and cannot be used. You might want to disable this on the server, but you need it enabled on the client.
+net-irc/quassel:breeze - Support the Breeze and Breeze-Dark icon sets (default for Plasma 5).
+net-irc/quassel:crypt - Support core->network per-channel and per-query blowfish encryption via app-crypt/qca SLOT 2.
+net-irc/quassel:dbus - Support desktop notifications via the StatusNotifier D-Bus service (used by most modern desktop environments).
+net-irc/quassel:monolithic - Build standalone client with integrated core, no external quasselcore needed. Only useful if you don't want to use Quassel's client/server model. The server and X flags are not needed in this case but it is possible to enable them too.
+net-irc/quassel:oxygen - Support the Oxygen icon set that was the default for KDE4.
+net-irc/quassel:phonon - Build client with phonon backend support. This enables sound playback in client.
+net-irc/quassel:server - Build the server binary. If this USE flag is disabled, the 'core' server binary for quassel is not built, and cannot be used. You need this enabled on the server, but you might want to disable it on the client.
+net-irc/quassel:snorenotify - Support for Snore notification framework.
+net-irc/quassel:urlpreview - Use QtWebEngine rendering engine for showing URL thumbnails.
+net-irc/rbot:aspell - Use aspell instead of ispell in the "spell" plugin for rbot. The vanilla plugin uses ispell, but enabling this flag makes it use the ispell interface from aspell instead.
+net-irc/rbot:cal - Add dependency over a package providing the /usr/bin/cal command, which is needed to enable the "cal" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/rbot:figlet - Add dependency over app-misc/figlet, which is used by the "figlet" plugin for rbot. If the USE flag is disabled the plugin will be unable to use figlet; if toilet is also disabled, the plugin will be disabled.
+net-irc/rbot:fortune - Add dependency over games-misc/fortune-mod, which is needed to enable the "fortune" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/rbot:host - Add dependency over net-dns/bind-tools (providing /usr/bin/host), which is needed to enable the "host" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/rbot:nls - Build and install translation for the messages coming from the bot and its plugins (through dev-ruby/ruby-gettext).
+net-irc/rbot:shorturl - Add dependency over dev-ruby/shorturl, which is needed to enable the "shortenurl" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/rbot:timezone - Add dependency over dev-ruby/tzinfo to enable the "time" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/rbot:toilet - Add dependency over app-misc/toilet, which is used by the "figlet" plugin for rbot. If the USE flag is disabled the plugin will be unable to use toilet; if figlet is also disabled, the plugin will be disabled.
+net-irc/rbot:translator - Add dependency over dev-ruby/mechanize, which is needed to enable the "translator" plugin for rbot. If the USE flag is disabled the plugin is also disabled by default.
+net-irc/shadowircd:largenet - Enable support/tweaks for large networks
+net-irc/unrealircd:class-nofakelag - Enable an unsupported class::options flag called “nofakelag” allowing you to grant fakelag exemption to normal user (instead of just opers).
+net-irc/unrealircd:extban-stacking - Enable extended channel bans (such as +b ~c: and +b ~n:) to contain other extended bans instead of just hostmasks.
+net-irc/unrealircd:operoverride - Enable OperOverride extension
+net-irc/unrealircd:operoverride-verify - Enable requiring opers to invite themselves to +s/+p channels
+net-irc/unrealircd:prefixaq - Enable chanadmin and chanowner prefixes
+net-irc/unrealircd:showlistmodes - Display channel modes in /LIST (only configured at compiletime)
+net-irc/unrealircd:shunnotices - Enable notifying a user when un-shunned
+net-irc/unrealircd:topicisnuhost - Enable displaying nick!user@host as topic setter
+net-irc/unrealircd:usermod - Enable /set* and /chg* commands
+net-irc/weechat:alias - Enable plugin for alias control
+net-irc/weechat:buflist - Enable buflist plugin
+net-irc/weechat:charset - Enable encoding conversions
+net-irc/weechat:exec - Enable exec plugin
+net-irc/weechat:fifo - Enable FIFO support (sh pipes)
+net-irc/weechat:fset - Enable fast set plugin
+net-irc/weechat:irc - Enable IRC protocol support
+net-irc/weechat:logger - Enable support for logging
+net-irc/weechat:relay - Enable relay plugin (experimental)
+net-irc/weechat:scripts - Build infrastructure for scripting
+net-irc/weechat:trigger - Enable trigger plugin
+net-irc/weechat:xfer - Enable xfer plugin support
+net-irc/znc:daemon - Allow znc to run as a system-wide service. Installs an init script and creates a znc user:group.
+net-irc/znc:zlib - Enable mod_deflate-like gzip support for znc's web interface using sys-libs/zlib.
+net-libs/aqbanking:chipcard - Enable support for DDV/RSA-chipcards
+net-libs/aqbanking:ebics - Enable support for Electronic Banking Internet Communication Standard (EBICS)
+net-libs/axtls:cgi-lua - Enables lua backed cgi for axhttpd server
+net-libs/axtls:cgi-php - Enables php backed cgi for axhttpd server
+net-libs/axtls:httpd - Enables axhttpd web server component
+net-libs/axtls:static - Statically build axhttpd server
+net-libs/c-client:chappa - Enable Eduardo Chappa's patches for use with mail-client/alpine (mainly adds support for maildir)
+net-libs/c-client:doc - Install RFCs related to IMAP
+net-libs/c-client:topal - Enable support for net-mail/topal for use with mail-client/alpine
+net-libs/courier-authlib:vpopmail - Enable vpopmail support
+net-libs/cvm:vpopmail - Enable vpopmail support
+net-libs/daq:afpacket - Build the AFPacket data acquisition module. Functions similar to the PCAP module but with better performance. Snort can run unprivileged when using this module. AFpacket supports both inline and passive modes.
+net-libs/daq:dump - Build the Dump data acquisition module. The dump DAQ allows you to test the various inline mode features available in 2.9 Snort like injection and normalization.
+net-libs/daq:ipq - Build the IPQ data acquisition module. IPQ is the old way to process iptables packets for inline deployments. Snort can not run unprivileged when using this module.
+net-libs/daq:nfq - Build the NFQ data acquisition module. NFQ is the new way to process iptables packets for inline deployments. Snort can not run unprivileged when using this module.
+net-libs/daq:pcap - Build the PCAP data acquisition module.
+net-libs/glib-networking:gnome - Extract HTTP/HTTPS/SOCKS proxy configuration stored using GSettings
+net-libs/glib-networking:libproxy - Use net-libs/libproxy for getting the HTTP/HTTPS/SOCKS proxy configuration
+net-libs/gnome-online-accounts:gnome - Use gnome-base/gnome-control-center to set GNOME online accounts preferences
+net-libs/gnutls:dane - Build libgnutls-dane, implementing DNS-based Authentication of Named Entities. Requires net-dns/unbound
+net-libs/gnutls:openpgp - Enable openpgp support
+net-libs/gnutls:openssl - Build openssl compatibility libraries
+net-libs/gnutls:pkcs11 - Add support for PKCS#11 through app-crypt/p11-kit
+net-libs/gnutls:sslv2 - Support for the old/insecure SSLv2 protocol
+net-libs/gnutls:sslv3 - Support for the old/insecure SSLv3 protocol
+net-libs/gnutls:test-full - Enable full test mode
+net-libs/gnutls:tls-heartbeat - Enable the Heartbeat Extension in TLS and DTLS
+net-libs/gnutls:tools - Build extra tools
+net-libs/gnutls:valgrind - Enable usage of dev-util/valgrind in debug
+net-libs/gtk-vnc:gtk3 - Build the gtk3 gtk-vnc library and other gtk3 assets
+net-libs/iax:snomhack - Use slower memset for SNOM phoneem
+net-libs/ldns:dane - Enable DNS-based Authentication of Named Entities (DANE) support
+net-libs/ldns:ecdsa - Enable ECDSA support
+net-libs/ldns:gost - Enable GOST support
+net-libs/libbitcoinconsensus:asm - Enable assembly for optimization
+net-libs/libbitcoinconsensus:knots - Build enhanced Bitcoin Knots version, rather than Bitcoin Core
+net-libs/libbtbb:extras - Install pcapdump and btaptap tools
+net-libs/libbtbb:wireshark-plugins - Build the wireshark plugins for bluetooth baseband sniffing
+net-libs/libeXosip:srv - enable support for SRV records DNS queries
+net-libs/libesmtp:ntlm - Enable support for NTLM authentication
+net-libs/libetpan:liblockfile - Enable support for liblockfile library
+net-libs/libgsasl:gcrypt - Use dev-libs/libgcrypt for low-level crypto
+net-libs/libgsasl:ntlm - Add support for Microsoft's NTLM mechanism using net-libs/libntlm
+net-libs/libinfinity:server - Build and install the server binary including init.d/conf.d-scripts. Needed if you want to host an infinote server for gobby.
+net-libs/libisds:openssl - Use dev-libs/openssl as crypto backend instead of app-crypt/gpgme and dev-libs/libgcrypt
+net-libs/libmicrohttpd:epoll - use epoll() system call
+net-libs/libmicrohttpd:messages - enable error messages
+net-libs/libnftnl:json - Supports parsing of JSON
+net-libs/libnids:glib - Use dev-libs/glib for multiprocessing support
+net-libs/libnids:libnet - Include code requiring net-libs/libnet
+net-libs/liboauth:bindist - Alias for the nss USE flag, since there are license compliancy trouble when using OpenSSL.
+net-libs/liboauth:curl - If enabled, net-misc/curl is used thorugh the libcurl library; if it's not, the curl command is used instead. Some features are only available when using the library, but using it as library requires matching SSL implementations.
+net-libs/liboauth:nss - Use Mozilla NSS (dev-libs/nss) as hash library; if this is disabled, dev-libs/openssl is used instead.
+net-libs/liboping:filecaps - Allow non-root users to use [n]oping utility.
+net-libs/liboping:ncurses - Build ncurses-based version of oping utility (requires sys-libs/ncurses)
+net-libs/libosmocore:embedded - Build for embedded use and disable unsupported features
+net-libs/libosmocore:pcsc-lite - Enable smartcard support with sys-apps/pcsc-lite
+net-libs/libpcap:netlink - Use dev-libs/libnl to put wireless interfaces in monitor mode.
+net-libs/libprotoident:tools - Build and install command-line tools
+net-libs/libproxy:gnome - Enable support for reading proxy settings from GNOME
+net-libs/libproxy:kde - Enable support for reading proxy settings from KDE
+net-libs/libproxy:spidermonkey - Use libmozjs from dev-lang/spidermonkey for PAC parsing
+net-libs/libproxy:webkit - Use libjavascriptcoregtk from net-libs/webkit-gtk for PAC parsing
+net-libs/libqmi:mbim - Support QMI over Mobile Broadband Interface Model (MBIM)
+net-libs/libsoup:gssapi - Enable GSSAPI support
+net-libs/libsoup:samba - Use net-fs/samba for NTLM Single Sign-On
+net-libs/libsrtp:aesicm - Use AES ICM cryptographic algorithm
+net-libs/libsrtp:console - Use /dev/console instead of stdout for error messages
+net-libs/libsrtp:openssl - Use OpenSSL crypto primitives
+net-libs/libsrtp:syslog - Use syslog for error messages
+net-libs/libssh:gcrypt - Prefer dev-libs/libgcrypt over dev-libs/openssl for encryption
+net-libs/libssh:gssapi - Enable gssapi support
+net-libs/libssh:pcap - Build with PCAP output support
+net-libs/libssh:server - Build with SSH server support
+net-libs/libssh:sftp - Build with SFTP support
+net-libs/libssh:ssh1 - Build with SSH1 support
+net-libs/libssh2:gcrypt - Use dev-libs/libgcrypt instead of dev-libs/openssl
+net-libs/libtorrent-rasterbar:dht - Enable DHT (distributed hash table) support
+net-libs/libtrace:numa - Use sys-process/numactl
+net-libs/libupnp:blocking-tcp - Do not use async socket calls.
+net-libs/libupnp:reuseaddr - Allow clean restarts by binding the socket with SO_REUSEADDR.
+net-libs/libupnp:samples - Install sample applications.
+net-libs/libvncserver:24bpp - enable 24bpp support
+net-libs/libvncserver:gcrypt - enable support for gcrypt
+net-libs/libwebsockets:access-log - Support generating Apache-compatible access logs
+net-libs/libwebsockets:cgi - Include CGI (spawn process with network-connected stdin/out/err) APIs
+net-libs/libwebsockets:client - The client part of the library and libwebsockets-test-client
+net-libs/libwebsockets:generic-sessions - With the Generic Sessions plugin
+net-libs/libwebsockets:http-proxy - Support for rewriting HTTP proxying
+net-libs/libwebsockets:http2 - Support the HTTP/2 protocol
+net-libs/libwebsockets:lejp - With the Lightweight JSON Parser
+net-libs/libwebsockets:libev - Support event loops via dev-libs/libev
+net-libs/libwebsockets:libuv - Support asynchronous I/O via dev-libs/libuv
+net-libs/libwebsockets:server-status - Support json + jscript server monitoring
+net-libs/libwebsockets:smtp - Provide SMTP support
+net-libs/libwebsockets:sqlite3 - Require SQLITE3 support
+net-libs/loudmouth:asyncns - Use net-libs/libasyncns for asynchronous name resolution.
+net-libs/loudmouth:openssl - Enable dev-libs/openssl support instead of gnutls (which is the default).
+net-libs/mbedtls:havege - Enable the HAVEGE random generator. Warning: the HAVEGE random generator is not suitable for virtualized environments
+net-libs/mbedtls:programs - Build PolarSSL programs
+net-libs/neon:libproxy - Add support for net-libs/libproxy
+net-libs/neon:pkcs11 - Add support for PKCS#11 using dev-libs/pakchois
+net-libs/nghttp2:hpack-tools - Install HPACK (header compression) helper tools
+net-libs/nghttp2:jemalloc - Use dev-libs/jemalloc for memory allocation
+net-libs/nghttp2:utils - Install nghttp, nghttpd and nghttpx
+net-libs/nodejs:inspector - Enable V8 inspector
+net-libs/nodejs:npm - Enable NPM package manager
+net-libs/nodejs:snapshot - Enable snapshot creation for faster startup
+net-libs/nodejs:systemtap - Enable SystemTAP/DTrace tracing
+net-libs/ntirpc:gssapi - Include support for RPCSEC GSS
+net-libs/ntirpc:rdma - Include support for RDMA RPC
+net-libs/onion:boehm-gc - Add dev-libs/boehm-gc support for memory allocations.
+net-libs/onion:libev - Use dev-libs/libev as thread poller instead of Linux's epoll.
+net-libs/onion:libevent - Use dev-libs/libevent as thread poller instead of libev or Linux's epoll.
+net-libs/onion:redis - Add support for redis sessions.
+net-libs/ortp:ntp-timestamp - Turn on NTP timestamping on received packet
+net-libs/ortp:srtp - Add support for Secure RTP
+net-libs/phodav:spice - Install the spice-webdavd guest agent
+net-libs/pjproject:amr - Inlcude AMR codec in the build
+net-libs/pjproject:epoll - Use /dev/epoll ioqueue on Linux (experimental)
+net-libs/pjproject:g711 - Include G.711 codecs in the build
+net-libs/pjproject:g722 - Include G.722 codec in the build
+net-libs/pjproject:g7221 - Include G.722.1 codec in the build
+net-libs/pjproject:ilbc - Include iLBC codec in the build
+net-libs/pjproject:l16 - Include Linear/L16 codec family in the build
+net-libs/pjproject:libyuv - Include libyuv in the build
+net-libs/pjproject:openh264 - Include Open H.264 support in the build
+net-libs/pjproject:opus - Include OPUS support in the build
+net-libs/pjproject:resample - Include resampling implementations in the build
+net-libs/pjproject:silk - Include SILK support in the build
+net-libs/pjproject:v4l2 - Include Video4Linux v2 support in the build
+net-libs/pjproject:webrtc - Enable WebRTC support
+net-libs/qxmpp:opus - Enable Opus codec support via media-libs/opus
+net-libs/qxmpp:vpx - Enable VP8 codec support via media-libs/libvpx
+net-libs/rabbitmq-c:tools - Builds cli tools to interact with brokers
+net-libs/shairplay:alac - Add support for Apple Lossless Audio Codec files
+net-libs/shairplay:static-libs - Build static versions of dynamic libraries as well
+net-libs/shairplay:tools - Build and install a binary shairplay in /usr/bin
+net-libs/telepathy-qt:farstream - Enable support for audio/video calls via farstream
+net-libs/tox:av - Adds support for audio and video.
+net-libs/tox:daemon - Enable the DHT Bootstrap Daemon.
+net-libs/tox:log-debug - Log level: 4
+net-libs/tox:log-error - Log level: 1
+net-libs/tox:log-info - Log level: 3
+net-libs/tox:log-trace - Log level: 5
+net-libs/tox:log-warn - Log level: 2
+net-libs/tox:no-log - Log level: 0 (no debug info logged)
+net-libs/tox:ntox - Enable the testing nTox client.
+net-libs/udns:tools - Build and install dnsget, ex-rdns and rblcheck tools
+net-libs/wandio:http - Build support for reading files over HTTP using net-misc/curl
+net-libs/webkit-gtk:coverage - Enable code coverage support
+net-libs/webkit-gtk:egl - Enable EGL support
+net-libs/webkit-gtk:geoloc - Enable geolocation support through app-misc/geoclue
+net-libs/webkit-gtk:geolocation - Enable geolocation support through app-misc/geoclue
+net-libs/webkit-gtk:gles2 - Enable GLESv2 support
+net-libs/webkit-gtk:nsplugin - Enable full nsplugin support (GTK2 plugins)
+net-libs/webkit-gtk:webgl - Build support for the WebGL HTML API using virtual/opengl
+net-libs/wvstreams:boost - Use dev-libs/boost to provide TR1-compatible functional interface. This USE flag is only needed with GCC earlier than version 4.1, or with other compilares not providing said interface.
+net-libs/xrootd:fuse - Enable the sys-fs/fuse filesystem driver
+net-libs/xrootd:http - Enable http protocol support
+net-libs/xrootd:rbd - Enable rados block device support via sys-cluster/ceph
+net-libs/zeromq:pgm - Build PGM (Pragmatic General Multicast)extention, a protocol for reliable multicast transport of data over IP networks.
+net-libs/zeromq:sodium - Use dev-libs/libsodium for cryptography
+net-mail/automx:memcached - Enable memcached support
+net-mail/automx:sql - Enable support for SQL backends
+net-mail/automx:tools - Install additional automx-test tool
+net-mail/courier-imap:trashquota - include deleted messages, and the Trash folder, in the estimated quota usage for maildirs
+net-mail/cyrus-imapd:backup - Enable backup service support
+net-mail/cyrus-imapd:calalarm - Enable CalDAV alarm support
+net-mail/cyrus-imapd:http - Enable http support
+net-mail/cyrus-imapd:jmap - Enable JMAP support
+net-mail/cyrus-imapd:lmdb - Enable support for using dev-db/lmdb
+net-mail/cyrus-imapd:replication - Enable replication support
+net-mail/cyrus-imapd:server - Enable building server binaries
+net-mail/cyrus-imapd:sieve - Enable sieve support
+net-mail/cyrus-imapd:sphinx - Enable Sphinx search engine support
+net-mail/cyrus-imapd:xapian - Enable Xapian search engine support
+net-mail/dbmail:sieve - Enable sieve filter support
+net-mail/dovecot:argon2 - Add support for ARGON2 password schemes
+net-mail/dovecot:cydir - Add cydir storage support
+net-mail/dovecot:imapc - Add imap client storage support
+net-mail/dovecot:lucene - Add lucene full text search (FTS) support using dev-cpp/clucene
+net-mail/dovecot:lz4 - Add support for lz4 (de)compression
+net-mail/dovecot:lzma - Add support for lzma (de)compression
+net-mail/dovecot:managesieve - Add managesieve protocol support
+net-mail/dovecot:mdbox - Add mdbox storage support
+net-mail/dovecot:pop3c - Add pop3 client storage support
+net-mail/dovecot:sdbox - Add sdbox storage support
+net-mail/dovecot:sieve - Add sieve support
+net-mail/dovecot:solr - Add solr full text search (FTS) support
+net-mail/dovecot:textcat - Add libtextcat language guessing support for full text search (FTS)
+net-mail/dovecot:vpopmail - Add vpopmail support
+net-mail/fdm:courierauth - Add support for Courier authentication library
+net-mail/fetchmail:hesiod - Enable support for hesiod
+net-mail/fetchmail:socks - Enable support for socks proxy
+net-mail/fetchmail:tk - Enable support for Tk GUI toolkit, in particular it installs fetchmailconf
+net-mail/gnubiff:password - Enable save passwords to connect mail servers in user space
+net-mail/hotwayd:smtp - Build SMTP proxy (hotsmtpd)
+net-mail/isync:compat - Enable legacy utilities
+net-mail/lbdb:abook - Enables app-misc/abook support
+net-mail/lbdb:finger - Enables finger support
+net-mail/libpst:dii - enable dii support
+net-mail/mailutils:clients - Build client programs - frm maidag mail sieve messages readmsg dotlock movemail mimeview mh
+net-mail/mailutils:kyotocabinet - Enable Kyoto Cabinet database support
+net-mail/mailutils:servers - Build server programs - imap4d pop3d comsatd
+net-mail/mailutils:tokyocabinet - Enable Tokyo Cabinet database support
+net-mail/mairix:gnus - Add support for the marks propagation feature in GNUS (provided by app-editors/emacs or app-xemacs/gnus for XEmacs users)
+net-mail/mpop:libsecret - Enable libsecret support to store login credentials
+net-mail/mu:emacs - Install the mu4e mail client.
+net-mail/notmuch:crypt - Support decryption and verification of PGP/MIME messages and in Emacs UI - encryption; support also S/MIME signature verification since version 0.22
+net-mail/notmuch:doc - Install API documentation
+net-mail/notmuch:emacs - Install Emacs UI (the main one)
+net-mail/notmuch:mutt - Install helper script for Mutt
+net-mail/notmuch:nmbug - Install experimental tag sharing / pseudo-bug-tracking script for Notmuch (see http://notmuchmail.org/nmbug/)
+net-mail/notmuch:valgrind - Depend on dev-util/vagrind for test suite
+net-mail/offlineimap:sqlite - Enable runtime support for sqlite mail status backend.
+net-mail/qmailadmin:maildrop - Filter spam using maildrop
+net-mail/qpopper:apop - Enables the pop.auth file in /etc/pop.auth
+net-mail/qpopper:mailbox - Enables mail spool file is in home directory ~/Mailbox
+net-mail/tpop3d:authexternal - Enable authentication by an external program
+net-mail/tpop3d:flatfile - Enable authentication against /etc/passwd-style flat files
+net-mail/tpop3d:passwd - Enable /etc/passwd authentication
+net-mail/tpop3d:sha1 - Use OpenSSL for sha1 encrypted passwords.
+net-mail/tpop3d:shadow - Enable /etc/shadow authentication
+net-mail/uw-imap:clearpasswd - Enables cleartext logins outside of SSL sessions
+net-mail/vchkuser:debug - Enables debug messages to syslog
+net-mail/vpopmail:clearpasswd - Enables cleartext password storage in the vpasswd files
+net-mail/vpopmail:ipalias - Enables enable-ip-alias-domains
+net-mail/vpopmail:maildrop - Enables mail-filter/maildrop support in vdelivermail
+net-mail/vpopmail:spamassassin - Enables mail-filter/spamassassin support
+net-misc/apt-cacher-ng:fuse - Install the sys-fs/fuse based acngfs, to use a userspace filesystem for the apt cache.
+net-misc/aria2:bittorrent - Enable support for the bittorrent protocol.
+net-misc/aria2:jemalloc - Use dev-libs/jemalloc to replace the malloc() implementation with a possibly faster one
+net-misc/aria2:libuv - Use dev-libs/libuv backend.
+net-misc/aria2:libxml2 - Use dev-libs/libxml2 for XML parsing (preferred) instead of dev-libs/expat.
+net-misc/aria2:metalink - Enable support for metalink.
+net-misc/aria2:nettle - Use dev-libs/nettle and dev-libs/gmp for bittorrent/metalink crypto instead of dev-libs/libgcrypt (when dev-libs/openssl is not being used).
+net-misc/aria2:scripts - Install additional scripts which use aria2's xmlrpc functionality.
+net-misc/aria2:ssh - Enable SFTP support.
+net-misc/asterisk:cluster - Enable high-availability support through the Corosync Cluster Engine
+net-misc/asterisk:dahdi - Support Digium compatible hardware (formerly known as Zaptel).
+net-misc/asterisk:gtalk - Enable support for Google Talk services
+net-misc/asterisk:http - Enable embedded web server
+net-misc/asterisk:ilbc - Enable the Internet Low Bitrate Codec (iLBC)
+net-misc/asterisk:newt - Include additional tools that require redhats windowing toolkit
+net-misc/asterisk:osplookup - Support secure peering using the Open Settlement Protocol
+net-misc/asterisk:pjproject - Enable support for pjproject (pjsip)
+net-misc/asterisk:samples - Install sample sound and configuration files (default: on)
+net-misc/asterisk:span - Enable support for the spandsp codec
+net-misc/asterisk:srtp - Enable support for encrypted voice transmission (secure RTP)
+net-misc/asterisk-core-sounds:alaw - Install the sounds files for the alaw codec.
+net-misc/asterisk-core-sounds:g722 - Install the sounds files for the g722 codec.
+net-misc/asterisk-core-sounds:g729 - Install the sounds files for the g729 codec.
+net-misc/asterisk-core-sounds:siren14 - Install the sounds files for the siren14 codec.
+net-misc/asterisk-core-sounds:siren7 - Install the sounds files for the siren7 codec.
+net-misc/asterisk-core-sounds:sln16 - Install the sounds files for the sln16 codec.
+net-misc/asterisk-core-sounds:ulaw - Install the sounds files for the ulaw codec.
+net-misc/asterisk-core-sounds:wav - Install the sounds files for the wav codec.
+net-misc/asterisk-extra-sounds:alaw - Install the sounds files for the alaw codec.
+net-misc/asterisk-extra-sounds:g722 - Install the sounds files for the g722 codec.
+net-misc/asterisk-extra-sounds:g729 - Install the sounds files for the g729 codec.
+net-misc/asterisk-extra-sounds:gsm - Install the sounds files for the +gsm codec.
+net-misc/asterisk-extra-sounds:siren14 - Install the sounds files for the siren14 codec.
+net-misc/asterisk-extra-sounds:siren7 - Install the sounds files for the siren7 codec.
+net-misc/asterisk-extra-sounds:sln16 - Install the sounds files for the sln16 codec.
+net-misc/asterisk-extra-sounds:ulaw - Install the sounds files for the ulaw codec.
+net-misc/asterisk-extra-sounds:wav - Install the sounds files for the wav codec.
+net-misc/asterisk-moh-opsound:alaw - Install the sounds files for the alaw codec.
+net-misc/asterisk-moh-opsound:g722 - Install the sounds files for the g722 codec.
+net-misc/asterisk-moh-opsound:g729 - Install the sounds files for the g729 codec.
+net-misc/asterisk-moh-opsound:gsm - Install the sounds files for the +gsm codec.
+net-misc/asterisk-moh-opsound:siren14 - Install the sounds files for the siren14 codec.
+net-misc/asterisk-moh-opsound:siren7 - Install the sounds files for the siren7 codec.
+net-misc/asterisk-moh-opsound:sln16 - Install the sounds files for the sln16 codec.
+net-misc/asterisk-moh-opsound:ulaw - Install the sounds files for the ulaw codec.
+net-misc/asterisk-moh-opsound:wav - Install the sounds files for the wav codec.
+net-misc/batman-adv:bla - B.A.T.M.A.N. bridge loop avoidance
+net-misc/batman-adv:dat - B.A.T.M.A.N. distributed arp table
+net-misc/batman-adv:mcast - B.A.T.M.A.N. multicast optimizations
+net-misc/batman-adv:nc - B.A.T.M.A.N. network coding
+net-misc/bfgminer:adl - Enable support for controlling fans and overclocking on AMD cards with AMD Display Library
+net-misc/bfgminer:alchemist - Enable support for mining with AlcheMist
+net-misc/bfgminer:antminer - Enable support for mining with AntMiner U1 sticks
+net-misc/bfgminer:avalon - Enable support for mining with Avalon 1 ASIC modules
+net-misc/bfgminer:avalonmm - Enable support for mining with Avalon 2/3 ASIC modules
+net-misc/bfgminer:bfsb - Enable support for mining on BFSB host Raspberry Pi
+net-misc/bfgminer:bfx - Enable support for mining with BFx2 USB sticks
+net-misc/bfgminer:bifury - Enable support for mining with Bi*fury USB sticks
+net-misc/bfgminer:bigpic - Enable support for mining with Big Picture Mining USB sticks (Red/BlueFury, BF1, etc)
+net-misc/bfgminer:bitforce - Enable support for mining with ButterFly Labs BitFORCE ASICs and/or FPGAs
+net-misc/bfgminer:bitfury - Enable support for mining with 55nm Bitfury-based devices
+net-misc/bfgminer:bitmain - Enable support for mining with Bitmain Antminer S* series
+net-misc/bfgminer:cointerra - Enable support for mining with CoinTerra TerraMiner.
+net-misc/bfgminer:cpumining - Enable support for mining with CPUs
+net-misc/bfgminer:drillbit - Enable support for mining with Drillbit boards
+net-misc/bfgminer:dualminer - Enable support for mining with DualMiner USB sticks
+net-misc/bfgminer:gridseed - Enable support for mining with 5-chip GridSeed orbs
+net-misc/bfgminer:hashbuster - Enable support for mining with HashBuster nano boards
+net-misc/bfgminer:hashbuster2 - Enable support for mining with HashBuster micro boards
+net-misc/bfgminer:hashfast - Enable support for mining with HashFast devices
+net-misc/bfgminer:icarus - Enable support for mining with Icarus-compatible devices (including Block Erupter Sapphire ASICs)
+net-misc/bfgminer:jingtian - Enable support for mining on JingTian boards via SPI/GPIO
+net-misc/bfgminer:keccak - Enable support for mining with Keccak miners
+net-misc/bfgminer:klondike - Enable support for mining with Klondike USB miners
+net-misc/bfgminer:libusb - Use libusb
+net-misc/bfgminer:littlefury - Enable support for mining with LittleFury USB sticks
+net-misc/bfgminer:metabank - Enable support for mining on Metabank host Raspberry Pi
+net-misc/bfgminer:minion - Enable support for mining on minion chips via SPI (BlackArrow Prospero)
+net-misc/bfgminer:modminer - Enable support for mining with ModMiner FPGAs
+net-misc/bfgminer:nanofury - Enable support for mining with NanoFury USB sticks
+net-misc/bfgminer:opencl - Enable support for mining with OpenCL-capable devices (GPUs)
+net-misc/bfgminer:proxy - Enable support for virtual proxy device
+net-misc/bfgminer:proxy_getwork - Enable proxy support for getwork protocol (often used with Block Erupter Blades)
+net-misc/bfgminer:proxy_stratum - Enable proxy support for stratum protocol
+net-misc/bfgminer:rockminer - Enable support for mining with RockMiner devices
+net-misc/bfgminer:screen - Provide start-bfgminer.sh script to launch BFGMiner in app-misc/screen
+net-misc/bfgminer:scrypt - Enable support for scrypt mining algorithm
+net-misc/bfgminer:sha256d - Enable support for SHA256d mining algorithm
+net-misc/bfgminer:twinfury - Enable support for mining with Twinfury USB sticks
+net-misc/bfgminer:udev-broad-rules - Enable broader udev rules that may match non-mining devices
+net-misc/bfgminer:x6500 - Enable support for mining with X6500 FPGAs
+net-misc/bfgminer:zeusminer - Enable support for mining with ZeusMiner units
+net-misc/bfgminer:ztex - Enable support for mining with Ztex FPGAs
+net-misc/bird:client - Build the ncurses/readline full featured CLI
+net-misc/cfengine:html - Install HTML documentation
+net-misc/cfengine:libvirt - Enable support for virtual machine management through app-emulation/libvirt
+net-misc/cfengine:masterfiles - Install the Masterfiles Policy Framework
+net-misc/cfengine:qdbm - Use dev-db/qdbm as database backend
+net-misc/cfengine:tests - Install test files
+net-misc/cfengine:tokyocabinet - Use dev-db/tokyocabinet as database backend
+net-misc/cgminer:ants1 - Enable support for Antminer S1 Bitmain
+net-misc/cgminer:ants2 - Enable support for Antminer S2 Bitmain
+net-misc/cgminer:ants3 - Enable support for Antminer S3 Bitmain
+net-misc/cgminer:avalon - Enable support for Avalon ASICs
+net-misc/cgminer:avalon-miner - Enable support for Avalon miner ASICs
+net-misc/cgminer:avalon2 - Enable support for Avalon2 ASICs
+net-misc/cgminer:avalon4 - Enable support for Avalon4 ASICs
+net-misc/cgminer:avalon7 - Enable support for Avalon7 ASICs
+net-misc/cgminer:bab - Enable support for BlackArrow Bitfury
+net-misc/cgminer:bflsc - Enable support for BFL ASICs
+net-misc/cgminer:bitforce - Enable support for mining with ButterFly Labs BitFORCE FPGAs
+net-misc/cgminer:bitfury - Enable support for mining with BitFury ASICs
+net-misc/cgminer:bitmine_A1 - Enable support for mining with Bitmine.ch A1 ASICs
+net-misc/cgminer:blockerupter - Enable support for mining with BlockRupter ASICs
+net-misc/cgminer:cointerra - Enable support for mining with Cointerra ASICs
+net-misc/cgminer:drillbit - Enable support for mining with Drillbit BitFury ASICs
+net-misc/cgminer:hashfast - Enable support for mining with Hashfast
+net-misc/cgminer:hashratio - Enable support for mining with Hashratio
+net-misc/cgminer:icarus - Enable support for mining with Icarus FPGAs
+net-misc/cgminer:klondike - Enable support for mining with Klondik ASICs
+net-misc/cgminer:knc - Enable support for mining with KnC miners
+net-misc/cgminer:minion - Enable support for mining with BlackArrow Bitfury
+net-misc/cgminer:modminer - Enable support for mining with ModMiner FPGAs
+net-misc/cgminer:sp10 - Enable support for Spondoolies SP10
+net-misc/cgminer:sp30 - Enable support for Spondoolies SP30
+net-misc/chrony:adns - Support for asynchronous DNS
+net-misc/chrony:cmdmon - Support for command and monitoring
+net-misc/chrony:html - Install HTML documentation
+net-misc/chrony:ntp - Support for the Network Time Protocol (NTP)
+net-misc/chrony:phc - Support for the PTP (Precision Time Protocol) Hardware Clock (PHC) interface
+net-misc/chrony:pps - Support for the Linux Pulse Per Second (PPS) interface
+net-misc/chrony:refclock - Support for reference clocks
+net-misc/chrony:rtc - Support for the Linux Real Time Clock interface
+net-misc/connman:ethernet - Enable ethernet support.
+net-misc/connman:iptables - Use net-firewall/iptables as firewall.
+net-misc/connman:l2tp - Use net-dialup/xl2tpd for L2TP VPN support.
+net-misc/connman:nftables - Use net-firewall/nftables as firewall.
+net-misc/connman:ofono - Use net-misc/ofono for telephony support.
+net-misc/connman:openconnect - Use net-vpn/openconnect for VPN support.
+net-misc/connman:openvpn - Use net-vpn/openvpn for openvpn support.
+net-misc/connman:pptp - Use net-dialup/pptpclient for PPTP VPN support.
+net-misc/connman:tools - Enable testing tools.
+net-misc/connman:vpnc - Use net-vpn/vpnc for cisco VPN support.
+net-misc/connman:wispr - Enable support for WISPr hotspot logins.
+net-misc/connman-gtk:openconnect - Support easier authentication to AnyConnect VPNs
+net-misc/crossbar:tor - include tor services connections support
+net-misc/csync:sftp - Enable sftp transfer support via net-libs/libssh
+net-misc/curl:brotli - Enable brotli compression support
+net-misc/curl:http2 - Enabled HTTP/2.0 support
+net-misc/curl:metalink - Enable metalink support
+net-misc/curl:rtmp - Enable RTMP Streaming Media support
+net-misc/curl:ssh - Enabled SSH urls in curl using libssh2
+net-misc/curl:ssl - Enable crypto engine support (via openssl if USE='-gnutls -nss')
+net-misc/dahdi:flash - Support (short) flash on FXS
+net-misc/dahdi-tools:ppp - Enables PPP/DAHDIRAS support
+net-misc/dhcp:client - Install the dhclient program
+net-misc/dhcp:server - Install the dhcpd and dhcrelay programs
+net-misc/dhcpcd:embedded - Embed the definitions of dhcp options in the dhcpcd executable
+net-misc/dhcpcd-ui:gtk3 - Add support for x11-libs/gtk+ (The GIMP Toolkit)
+net-misc/dropbear:bsdpty - Add support for legacy BSD pty's rather than dynamic UNIX pty's -- do not use this flag unless you are absolutely sure you actually want it
+net-misc/dropbear:multicall - Build all the programs as one little binary (to save space)
+net-misc/dropbear:shadow - Enable shadow password support
+net-misc/dropbox:librsync-bundled - Use bundled librsync library
+net-misc/electron-cash:audio_modem - Enable plugin to support Audio Modem
+net-misc/electron-cash:cli - Enables the CLI interface
+net-misc/electron-cash:cosign - Enable plugin to support multisig wallets between multiple Electrum clients
+net-misc/electron-cash:digitalbitbox - Enable plugin to support Digital Bitbox hardware wallet
+net-misc/electron-cash:email - Enable plugin to support emailing invoices
+net-misc/electron-cash:qrcode - Enable QR code scanning with media-gfx/zbar
+net-misc/electron-cash:sync - Enable plugin to sync wallet metadata across multiple Electrum clients
+net-misc/electron-cash:vkb - Enable plugin for virtual keyboard
+net-misc/electrum:audio_modem - Enable plugin to support Audio Modem
+net-misc/electrum:cli - Enables the CLI interface
+net-misc/electrum:cosign - Enable plugin to support multisig wallets between multiple Electrum clients
+net-misc/electrum:digitalbitbox - Enable plugin to support Digital Bitbox hardware wallet
+net-misc/electrum:email - Enable plugin to support emailing invoices
+net-misc/electrum:greenaddress_it - Enable plugin to verify GreenAddress.it instant transactions
+net-misc/electrum:qrcode - Enable QR code scanning with media-gfx/zbar
+net-misc/electrum:sync - Enable plugin to sync wallet metadata across multiple Electrum clients
+net-misc/electrum:trustedcoin_com - Enable plugin to use two-factor service by TrustedCoin.com
+net-misc/electrum:vkb - Enable plugin for virtual keyboard
+net-misc/electrum-ltc:audio_modem - Enable plugin to support Audio Modem
+net-misc/electrum-ltc:cli - Enables the CLI interface
+net-misc/electrum-ltc:cosign - Enable plugin to support multisig wallets between multiple Electrum clients
+net-misc/electrum-ltc:digitalbitbox - Enable plugin to support Digital Bitbox hardware wallet
+net-misc/electrum-ltc:email - Enable plugin to support emailing invoices
+net-misc/electrum-ltc:qrcode - Enable QR code scanning with media-gfx/zbar
+net-misc/electrum-ltc:sync - Enable plugin to sync wallet metadata across multiple Electrum clients
+net-misc/electrum-ltc:vkb - Enable plugin for virtual keyboard
+net-misc/eventd:libcanberra - Enable plugin for sounds via media-libs/libcanberra
+net-misc/eventd:libnotify - Enable plugin to relay events to notification daemon (Note: not required for local notifications via net-misc/eventd)
+net-misc/eventd:notification - Enable plugin to display on-screen notifications
+net-misc/eventd:purple - Enable plugin for IM notifications via libpurple
+net-misc/eventd:speech - Enable plugin for Text-To-Speech support
+net-misc/eventd:webhook - Enable plugin to send payloads to webhook handlers
+net-misc/eventd:websocket - Enable support for WebSocket protocol
+net-misc/fatrat:bittorrent - Use the bittorrent protocol via net-libs/libtorrent-rasterbar.
+net-misc/felix:bird - Use BIRD, e.g. for route reflection
+net-misc/freerdp:client - Build client binaries
+net-misc/freerdp:openh264 - Enable H.264 support using media-libs/openh264
+net-misc/freerdp:server - Build server binaries
+net-misc/gerbera:curl - Support YouTube and external media sources (e.g. internet radio)
+net-misc/gerbera:ffmpegthumbnailer - Enable video thumbnail support with media-video/ffmpegthumbnailer
+net-misc/gerbera:lastfm - Enable last.fm support
+net-misc/gerbera:magic - Use libmagic to determine file types
+net-misc/gerbera:mysql - Use dev-db/mysql as backend rather than SQLite3
+net-misc/gerbera:protocol-extensions - Enable partial DLNA support
+net-misc/gerbera:taglib - Use media-libs/taglib for reading files' metadata rather than id3lib
+net-misc/gnome-online-miners:flickr - Enable Flickr support
+net-misc/gsasl:gcrypt - Use dev-libs/libgcrypt for low-level crypto
+net-misc/gsasl:ntlm - Add support for Microsoft's NTLM mechanism using net-libs/libntlm
+net-misc/guacamole-server:ssh - enable support for ssh connections
+net-misc/guacamole-server:telnet - enable support for telnet connections
+net-misc/gwget:epiphany - Build epiphany extensions
+net-misc/hotot:chrome - Build chrome browser extension
+net-misc/htbinit:esfq - Add support for Enhanced Stochastic Fairness queueing discipline.
+net-misc/hylafaxplus:html - Convert faxes into html email
+net-misc/hylafaxplus:jbig - JBIG Fax Compression Support
+net-misc/hylafaxplus:mgetty - Receive faxes via serial port connections
+net-misc/hylafaxplus:pam - hfaxd authentication via PAM
+net-misc/icaclient:l10n_zh_CN - Install Chinese translation
+net-misc/icecast:kate - Add karaoke and text encapsulation support for Ogg files
+net-misc/icecast:logrotate - Install support files for app-admin/logrotate?
+net-misc/icecast:yp - Build support for yp public directory listings
+net-misc/iputils:SECURITY_HAZARD - Allow non-root users to flood (ping -f). This is generally a very bad idea.
+net-misc/iputils:arping - Build and install arping -- tool for sending ARP requests to peers (see also net-analyzer/arping)
+net-misc/iputils:clockdiff - Build and install clockdiff -- tool for comparing clocks via ICMP packets
+net-misc/iputils:gcrypt - Use dev-libs/libgcrypt for md5 support
+net-misc/iputils:nettle - Use dev-libs/nettle for md5 support
+net-misc/iputils:openssl - Use dev-libs/openssl for md5 support
+net-misc/iputils:rarpd - Build and install rarpd -- server for handling RARP (reverse ARP) requests; generally only used by old systems
+net-misc/iputils:rdisc - Build and install rdisc -- server for the client side of the ICMP router discover protocol
+net-misc/iputils:tftpd - Build and install tftpd -- server for the Trivial File Transfer Protocol (see also net-ftp/tftp-hpa)
+net-misc/iputils:tracepath - Build and install tracepath -- tool for tracing network paths for discovering MTU values
+net-misc/iputils:traceroute - Build and install traceroute -- tool for tracing network paths (see also net-analyzer/traceroute)
+net-misc/kafka-bin:internal-zookeeper - Use bundled local zookeeper instance
+net-misc/kafkacat:json - Enable json support
+net-misc/kea:openssl - Use dev-libs/openssl instead of Botan
+net-misc/kea:samples - Install sample configuration files
+net-misc/knock:server - Installs the knockd server daemon.
+net-misc/lcr:asterisk - net-misc/asterisk channel driver
+net-misc/lcr:gsm-bs - net-wireless/openbsc driver
+net-misc/lcr:gsm-ms - net-wireless/osmobb driver
+net-misc/lcr:gsmhr - Support for GSM HR codec using reference code (very slow)
+net-misc/lcr:misdn - net-misc/misdn driver
+net-misc/lcr:sip - SIP support
+net-misc/lcr:ss5 - CCITT No. 5 support
+net-misc/libteam:zmq - Build witch net-libs/zeromq support
+net-misc/lldpd:cdp - Enable Cisco Discovery Protocol
+net-misc/lldpd:dot1 - Enable Dot1 extension (VLAN stuff)
+net-misc/lldpd:dot3 - Enable Dot3 extension (PHY stuff)
+net-misc/lldpd:edp - Enable Extreme Discovery Protocol
+net-misc/lldpd:fdp - Enable Foundry Discovery Protocol
+net-misc/lldpd:graph - Create dot graphs in documentations
+net-misc/lldpd:jansson - Enable JSON output via Jansson
+net-misc/lldpd:lldpmed - Enable LLDP-MED extension
+net-misc/lldpd:old-kernel - Enable compatibility with Linux kernel older than 2.6.39
+net-misc/lldpd:sanitizers - Enable code instrumentation with selected sanitizers
+net-misc/lldpd:snmp - Enable the use of SNMP
+net-misc/lldpd:sonmp - Enable SynOptics Network Management
+net-misc/megatools:fuse - Enables support for the filesystem in userspace plugin through sys-fs/fuse.
+net-misc/memcached:slabs-reassign - Allow manual reassignment of memory slabs at the cost of slab optimizations.
+net-misc/minidlna:netgear - Enable netgear branding
+net-misc/minidlna:readynas - Enable readynas branding
+net-misc/miniupnpd:igd2 - Build for IGDv2 instead of an IGDv1
+net-misc/miniupnpd:leasefile - Enable lease file.
+net-misc/miniupnpd:pcp-peer - Enable support for PCP-PEER to allow NAT-PMP clients to mangle their packets.
+net-misc/miniupnpd:portinuse - Check if a port is in use before allowing a NAT-PMP client to map it.
+net-misc/miniupnpd:strict - Be more strict regarding compliance with UPnP specifications.
+net-misc/modemmanager:mbim - Enable MBIM modem protocol
+net-misc/modemmanager:qmi - Enable support for the QMI modem protocol used by devices with Qualcomm chipsets
+net-misc/mosh:client - Build network client
+net-misc/mosh:examples - Include example scripts
+net-misc/mosh:mosh-hardening - Enable compiler and linker options to frustrate memory corruption exploits
+net-misc/mosh:server - Build network server
+net-misc/mosh:ufw - Install net-firewall/ufw rule set
+net-misc/mosh:utempter - Include libutempter support
+net-misc/mulk:checksum - Enable checksum verification for Metalink from dev-libs/openssl
+net-misc/mulk:metalink - Enable support for media-libs/libmetalink
+net-misc/ncp:diet - Compile against dev-libs/dietlibc
+net-misc/netkit-bootparamd:libtirpc - Build against net-libs/libtirpc for RPC support
+net-misc/networkmanager:connection-sharing - Use net-dns/dnsmasq and net-firewall/iptables for connection sharing
+net-misc/networkmanager:consolekit - Use sys-auth/consolekit for session tracking
+net-misc/networkmanager:dhclient - Use dhclient from net-misc/dhcp for getting ip
+net-misc/networkmanager:dhcpcd - Use net-misc/dhcpcd for getting ip
+net-misc/networkmanager:elogind - Use sys-auth/elogind for session tracking
+net-misc/networkmanager:json - Enable JSON validation via dev-libs/jansson in libnm.
+net-misc/networkmanager:modemmanager - Enable support for mobile broadband devices using net-misc/modemmanager
+net-misc/networkmanager:nss - Use dev-libs/nss for cryptography
+net-misc/networkmanager:ofono - Use net-misc/ofono for telephony support.
+net-misc/networkmanager:ovs - Enable OpenVSwitch support
+net-misc/networkmanager:ppp - Enable support for mobile broadband and PPPoE connections using net-dialup/ppp
+net-misc/networkmanager:resolvconf - Use net-dns/openresolv for managing DNS information
+net-misc/networkmanager:teamd - Enable Teamd control support
+net-misc/networkmanager:wext - Enable support for the deprecated Wext (Wireless Extensions) API; needed for some older drivers (e.g. ipw2200, ndiswrapper)
+net-misc/networkmanager:wifi - Enable support for wifi and 802.1x security using net-wireless/wpa_supplicant
+net-misc/nextcloud-client:dolphin - Install the kde-apps/dolphin extension
+net-misc/nextcloud-client:nautilus - Install the gnome-base/nautilus extension
+net-misc/nextcloud-client:sftp - Enable sftp transfer support via net-libs/libssh
+net-misc/nextcloud-client:shibboleth - Build support for Shibboleth single sign-on
+net-misc/ntp:openntpd - Allow ntp to be installed alongside openntpd
+net-misc/ntp:parse-clocks - Add support for PARSE clocks
+net-misc/ntp:samba - Provide support for Samba's signing daemon (needed for Active Directory domain controllers)
+net-misc/ntpsec:early - Drop root privileges early
+net-misc/ntpsec:gdb - Enable debugging with gdb
+net-misc/ntpsec:heat - Install contrib heat generating scripts
+net-misc/ntpsec:nist - Enable lockclock
+net-misc/ntpsec:ntpviz - Make visualizations of offsets, jiffies, etc.
+net-misc/ntpsec:rclock_arbiter - Arbiter 1088A/B GPS driver
+net-misc/ntpsec:rclock_generic - Enable support for generic time radios and GPSDOs
+net-misc/ntpsec:rclock_gpsd - Enable gpsd daemon support
+net-misc/ntpsec:rclock_hpgps - Hewlett Packard GPS driver
+net-misc/ntpsec:rclock_jjy - JJY driver
+net-misc/ntpsec:rclock_local - Support for undisciplined local clock (not recommended)
+net-misc/ntpsec:rclock_modem - NIST/USNO/PTB Modem Time Services
+net-misc/ntpsec:rclock_neoclock - NeoClock4X DCF77/TDF driver
+net-misc/ntpsec:rclock_nmea - NMEA GPS driver
+net-misc/ntpsec:rclock_oncore - Oncore driver
+net-misc/ntpsec:rclock_pps - PPS cesium clock driver
+net-misc/ntpsec:rclock_shm - Obtain refclock info from shared memory-segment
+net-misc/ntpsec:rclock_spectracom - Spectracom driver
+net-misc/ntpsec:rclock_trimble - Trimble driver
+net-misc/ntpsec:rclock_truetime - Trutime driver (deprecated)
+net-misc/ntpsec:rclock_zyfer - Zyfer driver
+net-misc/ntpsec:smear - Specify the interval over which a leap second is applied (experimental)
+net-misc/ntpsec:tests - Enable tests
+net-misc/ofono:atmodem - ETSI AT modem support.
+net-misc/ofono:bluetooth - Enable Bluetooth modem support using net-wireless/bluez.
+net-misc/ofono:cdmamodem - Enable CDMA modem support.
+net-misc/ofono:datafiles - Enable install configuration and data files.
+net-misc/ofono:dundee - Enable BlueTooth DUN deamon support.
+net-misc/ofono:isimodem - Enable PhoNet/ISI modem support.
+net-misc/ofono:phonesim - Enable phone Simulator support
+net-misc/ofono:provision - Enable GPRS provisioning support
+net-misc/ofono:qmimodem - Enable Qualcomm QMI modem support
+net-misc/ofono:tools - Enable testing tools
+net-misc/oidentd:masquerade - Enable support for masqueraded/NAT connections
+net-misc/olsrd:pud - Install the Node Position Update plugin
+net-misc/openntpd:libressl - Enable HTTPS TLS time constraint support using dev-libs/libressl
+net-misc/openssh:X509 - Adds support for X.509 certificate authentication
+net-misc/openssh:bindist - Disable EC/RC5 algorithms in OpenSSL for patent reasons.
+net-misc/openssh:hpn - Enable high performance ssh
+net-misc/openssh:ldap - Add support for storing SSH public keys in LDAP
+net-misc/openssh:ldns - Use LDNS for DNSSEC/SSHFP validation.
+net-misc/openssh:livecd - Enable root password logins for live-cd environment.
+net-misc/openssh:ssh1 - Support the legacy/weak SSH1 protocol
+net-misc/openssh:ssl - Enable additional crypto algorithms via OpenSSL
+net-misc/openvswitch:monitor - Build the Python and GUI dependent monitor applications
+net-misc/owncloud-client:dolphin - Install the kde-apps/dolphin extension
+net-misc/owncloud-client:nautilus - Install the gnome-base/nautilus extension
+net-misc/owncloud-client:sftp - Enable sftp transfer support via net-libs/libssh
+net-misc/owncloud-client:shibboleth - Build support for Shibboleth single sign-on
+net-misc/pavuk:hammer - Turn on chunky/hammer mode (DoS) in pavuk: when specified, pavuk will include features to stress test web sites using an ultrahigh performancereplay mechanism
+net-misc/plowshare:view-captcha - View captcha with aview
+net-misc/ps3mediaserver:multiuser - Allow renderer customization per-user.
+net-misc/ps3mediaserver:transcode - Install optional dependencies for transcoding support via media-video/mplayer
+net-misc/ps3mediaserver:tsmuxer - Install optional dependencies for transcoding support via media-video/tsmuxer
+net-misc/ptpd:debug - Enable debugging informations
+net-misc/ptpd:experimental - Enable experimental features
+net-misc/ptpd:ntp - Enable NTPD cooperation
+net-misc/ptpd:pcap - Require net-libs/libpcap to allow layer 2 (raw Ethernet) transport
+net-misc/ptpd:slave-only - Enable slave only operation (remove master mode functionality)
+net-misc/ptpd:snmp - Require net-analyzer/net-snmp to enable SNMP configuration
+net-misc/ptpd:statistics - Enable compution of statistics
+net-misc/putty:gtk - Build the PuTTY client which requires x11-libs/gtk+:2. Otherwise only the CLI tools puttygen, plink, pscp and psftp will be built.
+net-misc/quagga:bgpclassless - Apply unofficial patch to enable classless prefixes for BGP. Patch and information to be found at http://hasso.linux.ee/doku.php/english:network:quagga
+net-misc/quagga:fpm - Enable Forwarding Plane Manager support
+net-misc/quagga:multipath - Enable multipath routes support for any number of routes
+net-misc/quagga:nhrpd - Build Next Hop Resolution Protocol daemon
+net-misc/quagga:ospfapi - Enable OSPFAPI support for client applications accessing the OSPF link state database
+net-misc/quagga:pam - Add support for PAM (via sys-libs/pam) to the Quagga Virtual Terminal Interface Shell (vtysh); if the readline USE flag is disabled, this flag is ignored
+net-misc/quagga:protobuf - Enable support for dev-libs/protobuf
+net-misc/quagga:readline - Enable support for sys-libs/readline to provide the Quagga Virtual Terminal Interface Shell (vtysh)
+net-misc/quagga:tcp-zebra - Enable TCP zserv interface on port 2600 for Zebra/protocol-daemon communication. Unix domain sockets are chosen otherwise
+net-misc/rancid-git:git - Enable git (version control system) support
+net-misc/rdesktop:kerberos - Enable CredSPP support + Kerberos authentication with net-libs/libgssglue
+net-misc/rdesktop:pcsc-lite - Enable smartcard support with sys-apps/pcsc-lite driver
+net-misc/rdesktop:xrandr - Enable XRandR window extension support
+net-misc/remmina:spice - Support connecting to SPICE-enabled virtual machines
+net-misc/remmina:ssh - Enable support for SSH/SFTP protocol; see also 'vte'
+net-misc/remmina:telepathy - Enable telepathy support
+net-misc/rsync:stunnel - Provide helper scripts for using rsync via >=net-misc/stunnel-4
+net-misc/rygel:tracker - Install dependencies for the tracker plugin
+net-misc/rygel:transcode - Install dependencies for transcoding support
+net-misc/scponly:gftp - Enables gFTP compatibility
+net-misc/scponly:logging - Enables SFTP logging compatibility
+net-misc/scponly:passwd - Enables passwd compatibility
+net-misc/scponly:quota - Enables quota compatibility
+net-misc/scponly:rsync - Enables rsync compatibility with potential security risks
+net-misc/scponly:scp - Enables scp compatibility with potential security risks
+net-misc/scponly:sftp - Enables SFTP compatibility
+net-misc/scponly:subversion - Enables Subversion compatibility with potential security risks
+net-misc/scponly:unison - Enables Unison compatibility with potential security risks
+net-misc/scponly:wildcards - Enables wildcard processing with potential security risks
+net-misc/scponly:winscp - Enables WinSCP 2.0 compatibility with potential security risks
+net-misc/seafile-client:shibboleth - Build support for Shibboleth single sign-on
+net-misc/sitecopy:rsh - This allows the use of rsh (remote shell) and rcp (remote copy) for authoring websites. sftp is a much more secure protocol and is preferred.
+net-misc/sitecopy:webdav - Enable WebDav (Web-based Distributed Authoring and Versioning) support. This system allows users to collaborate on websites using a web based interface. See the ebuild for an FAQ page. Enables neon as well to handle webdav support.
+net-misc/sks:optimize - Enables bytecode optimization
+net-misc/slimrat:X - Install also GUI client
+net-misc/spice-gtk:dbus - Support for desktop integration such as automounting and other APIs exposed by your DE via D-Bus
+net-misc/spice-gtk:gstaudio - Using gstreamer backend as audio decodec support
+net-misc/spice-gtk:gstvideo - Using gstreamer backend as video decodec support
+net-misc/spice-gtk:gtk3 - Link against x11-libs/gtk+:3 instead of x11-libs/gtk+:2
+net-misc/spice-gtk:lz4 - Enable support for LZ4 compression using app-arch/lz4
+net-misc/spice-gtk:mjpeg - Enable builtin mjpeg video decoder
+net-misc/spice-gtk:policykit - Enable sys-auth/polkit support for the usbredir acl helper
+net-misc/spice-gtk:usbredir - Use sys-apps/usbredir to redirect USB devices to another machine over TCP
+net-misc/spice-gtk:webdav - Support for folder-sharing between guest and client using net-libs/phodav
+net-misc/sshrc:mosh - Install Support for mosh
+net-misc/stargazer:debug - Enable extra debug codepaths, like asserts and extra output.
+net-misc/stargazer:doc - Adds extra documentation (API, doc, etc).
+net-misc/stargazer:examples - Install examples, usually source code.
+net-misc/stargazer:module_auth_always_online - Enable build of "Always Online" authentication module for Stargazer.
+net-misc/stargazer:module_auth_freeradius - Enable build of "Radius" authentication module for Stargazer. This module capable of using RADIUS procotol for user authentication.
+net-misc/stargazer:module_auth_internet_access - Enable build of "InetAccess" authentication module for Stargazer. InetAccess is a Stargazer specific authentication protocol.
+net-misc/stargazer:module_capture_ether - Enable build of "Ethernet" traffic capture module for Stargazer. This module uses RAW sockets to capture traffic.
+net-misc/stargazer:module_capture_ipq - Enable build of "IPQ" traffic capture module for Stargazer. This module uses IPQ subsystem to capture traffic.
+net-misc/stargazer:module_capture_netflow - Enable build of "NetFlow" traffic capture module for Stargazer. This module capable of receiving traffic data by NetFlow protocol.
+net-misc/stargazer:module_config_rpcconfig - Enable build of "XMLRPC" configuration module for Stargazer. This module uses XML-RPC protocol for configuring Stargazer.
+net-misc/stargazer:module_config_sgconfig - Enable build of "SGConf" configuration module for Stargazer. This module uses Stargazer specific protocol for configuring Stargazer.
+net-misc/stargazer:module_other_ping - Enable build of "Ping" module for Stargazer. This module pings connected users from time to time to ensure they are alive.
+net-misc/stargazer:module_other_remote_script - Enable build of "Remote Script" module for Stargazer. This module control rscriptd daemon over the net and makes it execute scripts in reaction to different Stargazer events.
+net-misc/stargazer:module_other_smux - Enable build of SMUX module for Stargazer. This module uses SMUX protocol to provide various information about Stargazer.
+net-misc/stargazer:module_store_files - Enable build of storage plugin for Stargazer based on plain files.
+net-misc/stargazer:module_store_firebird - Enable build of storage plugin for Stargazer, which uses Firebird database for storage.
+net-misc/stargazer:module_store_mysql - Enable build of storage plugin for Stargazer, which uses MySQL for storage.
+net-misc/stargazer:module_store_postgres - Enable build of storage plugin for Stargazer, which uses PostgreSQL for storage.
+net-misc/stargazer:radius - Enable build of FreeRADIUS module for data access via Stargazer.
+net-misc/stargazer:rscriptd - Enable build of remote script execute daemon for Stargazer, which run scripts when receive special signal from Stargazer.
+net-misc/stargazer:sgauth - Enable build of command-line utility for authorization in Stargazer.
+net-misc/stargazer:sgconf - Enable build of command-line utility for configuring Stargazer.
+net-misc/stargazer:sgconf_xml - Enable build of command-line xml-based utility for configuring Stargazer.
+net-misc/stargazer:sgconv - Enable build of utility to convert Stargazer data between storage backends.
+net-misc/stargazer:stargazer - Enable build of Stargazer billing system.
+net-misc/stargazer:static-libs - Install static libraries.
+net-misc/streamtuner:shout - Enable shoutcast plug-in.
+net-misc/streamtuner:xiph - Enable xiph.org plug-in.
+net-misc/stunnel:stunnel3 - Install the stunnel3 wrapper.
+net-misc/teamviewer:system-wine - Use virtual/wine instead of bundled wine.
+net-misc/termpkg:uucp - Adds support for uucp style device locking
+net-misc/tigervnc:dri3 - Build with DRI3 support
+net-misc/tigervnc:drm - Build with DRM support
+net-misc/tigervnc:server - Build TigerVNC server
+net-misc/tigervnc:xorgmodule - Build the Xorg module
+net-misc/trackma:cli - Enable cli version
+net-misc/trackma:ncurses - Enable curses version
+net-misc/uftp:server - Install uftp server daemon
+net-misc/vde:pcap - Enable the pcap-based plugin that allows creating a switch against a real interface.
+net-misc/vde:ssl - Enable the cryptcab plugin that allows creating an encrypted virtual cable.
+net-misc/vinagre:spice - Enable access to SPICE-enabled virtual machines
+net-misc/vinagre:ssh - Enable ssh plugin using x11-libs/vte
+net-misc/vinagre:telepathy - Enable access to remote desktop via a net-libs/telepathy-glib client
+net-misc/vino:telepathy - Enable desktop sharing through a telepathy client
+net-misc/wget:ntlm - Enable support for NTLM (Windows-based) authorization
+net-misc/wget:uuid - Generate UUIDs for the WARC (Web ARChive file format) using libuuid; otherwise use a simple RNG (random number generator)
+net-misc/wicd:ambiance - Install icons from Ubuntu's ambiance theme
+net-misc/wicd:gnome-shell - Install gnome-shell extension
+net-misc/wicd:gtk - Installs a gtk UI. This is enabled by default because it is intended behavior. Requires dev-python/pygtk
+net-misc/wicd:ioctl - Installs additional python libraries to use as a backend. This will improve speed but is experimental.
+net-misc/wicd:mac4lin - Change default icons to mac4lin icon set
+net-misc/wicd:ncurses - Installs a ncurses UI
+net-misc/wicd:pm-utils - Installs the pm-utils hooks for suspend/resume and requires sys-power/pm-utils
+net-misc/x2goserver:fuse - Use net-fs/sshfs to allow shared folders
+net-misc/youtube-viewer:gtk - Install the gtk GUI, called gtk-youtube-viewer
+net-nds/389-ds-base:auto-dn-suffix - Enable auto bind with auto dn suffix over unix domain socket (LDAPI) support
+net-nds/389-ds-base:autobind - Enable auto bind over unix domain socket (LDAPI) support
+net-nds/389-ds-base:bitwise - Enable bitwise plugin - supported data in raw/bitwise format
+net-nds/389-ds-base:dna - Enable dna (distributed numeric assignment ) plugin - to automatically assign unique uid numbers to new user entries as they are created.
+net-nds/389-ds-base:ldapi - Enable LDAP over unix domain socket (LDAPI) support
+net-nds/389-ds-base:pam-passthru - Enable pam-passthru plugin - for simple and fast system services used in ldap
+net-nds/389-ds-base:presence - Enable presence plugin - non-standard syntax validation
+net-nds/gosa-core:mail - Manage mail accounts and servers with gosa.
+net-nds/gosa-core:samba - Manage samba accounts with gosa.
+net-nds/ldapvi:gnutls - Use net-libs/gnutls instead of dev-libs/openssl
+net-nds/nsscache:nsscache - Depend on sys-auth/libnss-cache to handle flat files
+net-nds/nsscache:nssdb - Depend on sys-libs/libnss_db to handle dbm files.
+net-nds/openldap:experimental - Enable experimental backend options
+net-nds/openldap:kinit - Enable support for kerberos init
+net-nds/openldap:minimal - Build libraries & userspace tools only. Does not install any server code
+net-nds/openldap:odbc - Enable ODBC and SQL backend options
+net-nds/openldap:overlays - Enable contributed OpenLDAP overlays
+net-nds/openldap:pbkdf2 - Enable support for pbkdf2 passwords
+net-nds/openldap:sha2 - Enable support for pw-sha2 password hashes
+net-nds/openldap:smbkrb5passwd - Enable overlay for syncing ldap, unix and lanman passwords
+net-nds/rpcbind:warmstarts - Enables rpcbind to cache configuration for warm restarts
+net-nds/tac_plus:finger - Adds support for checking user counts via fingering the NAS
+net-nds/tac_plus:maxsess - Enforce a limit on maximum sessions per user
+net-news/rssguard:webengine - Use dev-qt/qtwebengine for embedded web browser
+net-nntp/inn:innkeywords - Enable automatic keyword generation support
+net-nntp/inn:inntaggedhash - Use tagged hash table for history (disables large file support)
+net-nntp/nzbget:parcheck - Enable support for checking PAR archives
+net-nntp/sabnzbd:7za - Add support for extracting 7za files
+net-nntp/sabnzbd:rar - Add support for extracting rar files
+net-nntp/sabnzbd:unzip - Add support for extracting zip files
+net-nntp/slrn:canlock - Add support for cancel locks via net-libs/canlock
+net-nntp/slrn:uudeview - Add support for yEnc coding and more using dev-libs/uulib
+net-nntp/tin:cancel-locks - Enable Cancel-Lock header functionality (also enables USE=evil)
+net-nntp/tin:etiquette - Enable the display off posting etiquettes
+net-nntp/tin:evil - Let tin generate a message ID
+net-nntp/tin:forgery - Cancel messages posted from a different account
+net-nntp/tin:gpg - Enable app-crypt/gnupg support
+net-p2p/airdcpp-webclient:nat-pmp - Enable support for the NAT-PMP protocol
+net-p2p/airdcpp-webclient:tbb - Enable support of the TBB library to improve performance
+net-p2p/airdcpp-webclient:webui - Enable the Web UI
+net-p2p/amule:daemon - Enable amule daemon
+net-p2p/amule:remote - Enable remote controlling of the client
+net-p2p/amule:stats - Enable statistic reporting
+net-p2p/bitcoin-cli:knots - Build enhanced Bitcoin Knots version, rather than Bitcoin Core
+net-p2p/bitcoin-cli:ljr - Enable Luke Dashjr's patches
+net-p2p/bitcoin-qt:asm - Enable assembly for optimization
+net-p2p/bitcoin-qt:bip70 - Enable support for the BIP70 payment protocol
+net-p2p/bitcoin-qt:bitcoin_policy_rbf - Replace By Fee policy: Your node will preferentially mine and relay transactions paying the highest fee, regardless of receive order
+net-p2p/bitcoin-qt:bitcoin_policy_spamfilter - Enhanced spam filter policy: Notorious spammers will not be assisted by your node
+net-p2p/bitcoin-qt:http - Enable support for the JSON-RPC and REST HTTP server (builtin net-p2p/bitcoind)
+net-p2p/bitcoin-qt:knots - Build enhanced Bitcoin Knots version, rather than Bitcoin Core
+net-p2p/bitcoin-qt:libevent - Use dev-libs/libevent
+net-p2p/bitcoin-qt:linguas_af - Afrikaans locale
+net-p2p/bitcoin-qt:linguas_af_ZA - Afrikaans locale for South Africa
+net-p2p/bitcoin-qt:linguas_ar - Arabic locale
+net-p2p/bitcoin-qt:linguas_be_BY - Belarusian locale for Belarus
+net-p2p/bitcoin-qt:linguas_bg - Bulgarian locale
+net-p2p/bitcoin-qt:linguas_bg_BG - Bulgarian locale for Bulgaria
+net-p2p/bitcoin-qt:linguas_ca - Catalan locale
+net-p2p/bitcoin-qt:linguas_ca@valencia - Catalan (Valencian) locale
+net-p2p/bitcoin-qt:linguas_ca_ES - Catalan locale for Spain
+net-p2p/bitcoin-qt:linguas_cs - Czech locale
+net-p2p/bitcoin-qt:linguas_cs_CZ - Czech locale for Czech Republic
+net-p2p/bitcoin-qt:linguas_cy - Welsh locale
+net-p2p/bitcoin-qt:linguas_da - Danish locale
+net-p2p/bitcoin-qt:linguas_de - German locale
+net-p2p/bitcoin-qt:linguas_el - Modern Greek locale
+net-p2p/bitcoin-qt:linguas_el_GR - Modern Greek locale for Greece
+net-p2p/bitcoin-qt:linguas_en - English locale
+net-p2p/bitcoin-qt:linguas_en_GB - English locale for United Kingdom
+net-p2p/bitcoin-qt:linguas_eo - Esperanto locale
+net-p2p/bitcoin-qt:linguas_es - Spanish locale
+net-p2p/bitcoin-qt:linguas_es_AR - Spanish locale for Argentina
+net-p2p/bitcoin-qt:linguas_es_CL - Spanish locale for Chile
+net-p2p/bitcoin-qt:linguas_es_CO - Spanish locale for Colombia
+net-p2p/bitcoin-qt:linguas_es_DO - Spanish locale for Dominican Republic
+net-p2p/bitcoin-qt:linguas_es_ES - Spanish locale for Spain
+net-p2p/bitcoin-qt:linguas_es_MX - Spanish locale for Mexico
+net-p2p/bitcoin-qt:linguas_es_UY - Spanish locale for Uruguay
+net-p2p/bitcoin-qt:linguas_es_VE - Spanish locale for Venezuela
+net-p2p/bitcoin-qt:linguas_et - Estonian locale
+net-p2p/bitcoin-qt:linguas_et_EE - Estonian locale for Estonia
+net-p2p/bitcoin-qt:linguas_eu_ES - Basque locale for Spain
+net-p2p/bitcoin-qt:linguas_fa - Persian locale
+net-p2p/bitcoin-qt:linguas_fa_IR - Persian locale for Iran
+net-p2p/bitcoin-qt:linguas_fi - Finnish locale
+net-p2p/bitcoin-qt:linguas_fr - French locale
+net-p2p/bitcoin-qt:linguas_fr_CA - French locale for Canada
+net-p2p/bitcoin-qt:linguas_fr_FR - French locale for France
+net-p2p/bitcoin-qt:linguas_gl - Galician locale
+net-p2p/bitcoin-qt:linguas_he - Hebrew locale
+net-p2p/bitcoin-qt:linguas_hi_IN - Hindi locale for India
+net-p2p/bitcoin-qt:linguas_hr - Croatian locale
+net-p2p/bitcoin-qt:linguas_hu - Hungarian locale
+net-p2p/bitcoin-qt:linguas_id_ID - Indonesian locale for Indonesia
+net-p2p/bitcoin-qt:linguas_it - Italian locale
+net-p2p/bitcoin-qt:linguas_it_IT - Italian locale for Italy
+net-p2p/bitcoin-qt:linguas_ja - Japanese locale
+net-p2p/bitcoin-qt:linguas_ka - Georgian locale
+net-p2p/bitcoin-qt:linguas_kk_KZ - Kazakh locale for Kazakhstan
+net-p2p/bitcoin-qt:linguas_ko_KR - Korean locale for Republic of Korea
+net-p2p/bitcoin-qt:linguas_ku_IQ - Kurdish locale for Iraq
+net-p2p/bitcoin-qt:linguas_ky - Kirghiz locale
+net-p2p/bitcoin-qt:linguas_la - Latin locale
+net-p2p/bitcoin-qt:linguas_lt - Lithuanian locale
+net-p2p/bitcoin-qt:linguas_lv_LV - Latvian locale for Latvia
+net-p2p/bitcoin-qt:linguas_mk_MK - Macedonian locale for Macedonia
+net-p2p/bitcoin-qt:linguas_mn - Mongolian locale
+net-p2p/bitcoin-qt:linguas_ms_MY - Malay locale for Malaysia
+net-p2p/bitcoin-qt:linguas_nb - Norwegian Bokmål locale
+net-p2p/bitcoin-qt:linguas_ne - Nepali locale
+net-p2p/bitcoin-qt:linguas_nl - Dutch locale
+net-p2p/bitcoin-qt:linguas_nl_NL - Dutch locale for Netherlands
+net-p2p/bitcoin-qt:linguas_pam - Kapampangan locale
+net-p2p/bitcoin-qt:linguas_pl - Polish locale
+net-p2p/bitcoin-qt:linguas_pt_BR - Portuguese locale for Brazil
+net-p2p/bitcoin-qt:linguas_pt_PT - Portuguese locale for Portugal
+net-p2p/bitcoin-qt:linguas_ro - Romanian locale
+net-p2p/bitcoin-qt:linguas_ro_RO - Romanian locale for Romania
+net-p2p/bitcoin-qt:linguas_ru - Russian locale
+net-p2p/bitcoin-qt:linguas_ru_RU - Russian locale for Russia
+net-p2p/bitcoin-qt:linguas_sk - Slovak locale
+net-p2p/bitcoin-qt:linguas_sl_SI - Slovenian locale for Slovenia
+net-p2p/bitcoin-qt:linguas_sq - Albanian locale
+net-p2p/bitcoin-qt:linguas_sr - Serbian locale
+net-p2p/bitcoin-qt:linguas_sr@latin - Serbian (Latin) locale
+net-p2p/bitcoin-qt:linguas_sv - Swedish locale
+net-p2p/bitcoin-qt:linguas_ta - Tamil locale
+net-p2p/bitcoin-qt:linguas_th_TH - Thai locale for Thailand
+net-p2p/bitcoin-qt:linguas_tr - Turkish locale
+net-p2p/bitcoin-qt:linguas_tr_TR - Turkish locale for Turkey
+net-p2p/bitcoin-qt:linguas_uk - Ukrainian locale
+net-p2p/bitcoin-qt:linguas_ur_PK - Urdu locale for Pakistan
+net-p2p/bitcoin-qt:linguas_uz@Cyrl - Uzbek (Cyrillic) locale
+net-p2p/bitcoin-qt:linguas_vi - Vietnamese locale
+net-p2p/bitcoin-qt:linguas_vi_VN - Vietnamese locale for Vietnam
+net-p2p/bitcoin-qt:linguas_zh - Chinese locale
+net-p2p/bitcoin-qt:linguas_zh_CN - Chinese locale for China
+net-p2p/bitcoin-qt:linguas_zh_HK - Chinese locale for Hong Kong
+net-p2p/bitcoin-qt:linguas_zh_TW - Chinese locale for Taiwan
+net-p2p/bitcoin-qt:ljr - Enable Luke Dashjr's patches
+net-p2p/bitcoin-qt:qrcode - Enable generation of QR Codes for receiving payments
+net-p2p/bitcoin-qt:tor - Enable automatic configuration of a Tor hidden service
+net-p2p/bitcoin-qt:upnp - Enable Universal Plug and Play
+net-p2p/bitcoin-qt:wallet - Enable wallet support
+net-p2p/bitcoin-qt:zeromq - Report blocks and transactions via zeromq
+net-p2p/bitcoind:asm - Enable assembly for optimization
+net-p2p/bitcoind:bitcoin_policy_rbf - Replace By Fee policy: Your node will preferentially mine and relay transactions paying the highest fee, regardless of receive order
+net-p2p/bitcoind:bitcoin_policy_spamfilter - Enhanced spam filter policy: Notorious spammers will not be assisted by your node
+net-p2p/bitcoind:knots - Build enhanced Bitcoin Knots version, rather than Bitcoin Core
+net-p2p/bitcoind:ljr - Enable Luke Dashjr's patches
+net-p2p/bitcoind:upnp - Enable Universal Plug and Play
+net-p2p/bitcoind:wallet - Enable wallet support
+net-p2p/bitcoind:zeromq - Report blocks and transactions via zeromq
+net-p2p/datacoin-hp:logrotate - Use app-admin/logrotate for rotating logs
+net-p2p/dbhub:switch_user - Enable support for switching user
+net-p2p/deluge:console - Enable default console UI
+net-p2p/deluge:webinterface - Install dependencies needed for the web interface
+net-p2p/eiskaltdcpp:cli - Enable sample cli based on readline
+net-p2p/eiskaltdcpp:daemon - Enable eiskaltdcpp-daemon
+net-p2p/eiskaltdcpp:dht - Enable DHT (distributed hash table) support for libeiskaltdcpp
+net-p2p/eiskaltdcpp:json - Enable JSON for cli and daemon
+net-p2p/eiskaltdcpp:libcanberra - Enable sound notifications support over libcanberra in EiskaltDC++ Gtk
+net-p2p/eiskaltdcpp:minimal - Don't install headers
+net-p2p/fms:frost - Add support for frost boards
+net-p2p/go-ethereum:devtools - Build Ethereum development tools (evm, abigen, puppeth, ...)
+net-p2p/go-ethereum:opencl - Add OpenCL GPU mining support
+net-p2p/go-ipfs-bin:fuse - Enable runtime support for sys-fs/fuse
+net-p2p/ktorrent:bwscheduler - Schedule upload and download limits over a period of a week
+net-p2p/ktorrent:downloadorder - Specify the download order of a multi-file torrent
+net-p2p/ktorrent:infowidget - Displays general information about a torrent in several tabs
+net-p2p/ktorrent:ipfilter - Filter IP addresses through a blocklist
+net-p2p/ktorrent:kross - Enable kross scripting support
+net-p2p/ktorrent:logviewer - Displays the logging output
+net-p2p/ktorrent:magnetgenerator - Generates magnet URI's
+net-p2p/ktorrent:mediaplayer - Phonon-based media player
+net-p2p/ktorrent:rss - Syndication plugin for KTorrent, supporting RSS and Atom feeds
+net-p2p/ktorrent:scanfolder - Scan folders for torrent files and load them
+net-p2p/ktorrent:search - Search for torrents
+net-p2p/ktorrent:shutdown - Shutdown when done
+net-p2p/ktorrent:stats - Shows statistics about torrents in several graphs
+net-p2p/ktorrent:upnp - Forward ports using UPnP
+net-p2p/ktorrent:zeroconf - Discover peers on the local network using the Zeroconf protocol
+net-p2p/litecoind:logrotate - Use app-admin/logrotate for rotating logs
+net-p2p/litecoind:wallet - Enable wallet support
+net-p2p/mldonkey:bittorrent - enable bittorrent support
+net-p2p/mldonkey:fasttrack - enable fasttrack support
+net-p2p/mldonkey:gnutella - enable gnutella and gnutella2 support
+net-p2p/mldonkey:guionly - enable client build only
+net-p2p/mldonkey:magic - enable use of libmagic
+net-p2p/ppcoind:logrotate - Use app-admin/logrotate for rotating logs
+net-p2p/pybitmessage:opencl - Uses dev-python/pyopencl for GPU acceleration.
+net-p2p/qbittorrent:webui - Enable the Web UI
+net-p2p/resilio-sync:pax_kernel - Use paxctl to mark binaries
+net-p2p/retroshare:cli - Enables the CLI version of RetroShare
+net-p2p/retroshare:feedreader - Enables the Feedreader plugin
+net-p2p/retroshare:gnome-keyring - Enables potentially insecure autologin capability via Gnome Keyring
+net-p2p/retroshare:gui - Enables the GUI version of RetroShare
+net-p2p/retroshare:voip - Enables VOIP plugin
+net-p2p/rtorrent:daemon - Uses app-misc/screen to daemonize this application
+net-p2p/syncthing:tools - Install stdiscosrv, strelaysrv and other tools to /usr/libexec/syncthing/.
+net-p2p/transmission:lightweight - Optimize transmission for low-resource systems (smaller cache size, prefer unencrypted peer connections, etc.)
+net-p2p/transmission:mbedtls - Use mbed TLS instead of OpenSSL
+net-p2p/transmission:xfs - Enable XFS filesystem capabilities by using sys-fs/xfsprogs headers (in building of fdlimit(.c))
+net-p2p/transmission-remote-gtk:libproxy - Use net-libs/libproxy for getting the HTTP/HTTPS/SOCKS proxy configuration.
+net-p2p/tribler:vlc - Enable vlc support.
+net-p2p/xmr-stak:cuda - Enable NVIDIA CUDA toolkit support
+net-p2p/xmr-stak:devfee - Enable payment of devfee to the developer
+net-p2p/xmr-stak:hwloc - Enable CPU affinity support via hwloc
+net-p2p/xmr-stak:opencl - Enable OpenCL support
+net-p2p/xmr-stak:webserver - Enable internal webserver
+net-print/cups:java - Add support for the Java interpeter in the web server CGIs.
+net-print/cups:lprng-compat - Do not install lp... binaries so cups and lprng can coexist.
+net-print/cups:python - Add support for the Python interpeter in the web server CGIs.
+net-print/cups-filters:foomatic - Build the included foomatic-rip printer driver. Strongly recommended.
+net-print/cups-filters:ipp_autosetup - Let cups-browsed automatically set up IPP network printers by default.
+net-print/cups-filters:pclm - Enable PCLm support
+net-print/fax4cups:efax - Install net-misc/efax backend
+net-print/fax4cups:hylafax - Install net-misc/hylafax backend
+net-print/fax4cups:mgetty-fax - Install net-dialup/mgetty backend
+net-print/hplip:X - Enables scanner GUI dependencies with USE="scanner" where media-gfx/xsane is preferred over media-gfx/sane-frontends
+net-print/hplip:fax - Enable fax on multifunction devices which support it
+net-print/hplip:hpcups - Build the hpcups driver for cups (by HP)
+net-print/hplip:hpijs - Build the IJS driver for cups (Foomatic)
+net-print/hplip:kde - Enables kde-misc/skanlite as scanner GUI with USE="scanner X"
+net-print/hplip:libusb0 - Depend on virtual/libusb SLOT 0. Some old printers do not work with virtual/libusb SLOT 1.
+net-print/hplip:minimal - Only build internal hpijs/hpcups driver (not recommended at all, make sure you know what you are doing)
+net-print/hplip:parport - Enable parallel port for devices which require it
+net-print/hplip:scanner - Enable scanner on multifunction devices which support it
+net-print/hplip:snmp - Add support for net-analyzer/net-snmp which enables this driver to work over networks (both for server and client)
+net-print/hplip:static-ppds - Use statically-generated PPDs instead of Dynamic PPDs. Although this is deprecated some printers may still need it to work properly. Use this flag if hp-setup fails to find/create a valid PPD file
+net-print/kyocera-1x2x-mfp-driver:rastertokpsl-fix - Use custom wrapper script to sanitize arguments before passing to 'rastertokpsl' filter program
+net-print/magicfilter:lprng-failsafe - Refuse options for compability with certain LPRng versions.
+net-proxy/haproxy:51degrees - Device Detection using 51 Degrees
+net-proxy/haproxy:device-atlas - Use dev-libs/device-atlas-api-c library
+net-proxy/haproxy:net_ns - Enable network namespace support (CONFIG_NET_NS)
+net-proxy/haproxy:pcre-jit - Use JIT support for PCRE
+net-proxy/haproxy:pcre2 - Enable PCRE2 RegEx support
+net-proxy/haproxy:pcre2-jit - Use JIT support for PCRE2
+net-proxy/haproxy:slz - Use dev-libs/libslz compression library
+net-proxy/haproxy:tools - Install additional tools (halog, iprange)
+net-proxy/haproxy:wurfl - Device Detection using WURFL
+net-proxy/privoxy:client-tags - Enable support for client-specific tags
+net-proxy/privoxy:compression - Allow privoxy to compress buffered content before sending to the client, if it supports it
+net-proxy/privoxy:editor - Enable the web-based actions file editor
+net-proxy/privoxy:extended-host-patterns - Enable and require PCRE syntax in host patterns. You must convert action files to PCRE, see privoxy-url-pattern-translator.pl Use at your own risk!
+net-proxy/privoxy:external-filters - Allow to filter content with scripts and programs. Experimental
+net-proxy/privoxy:fast-redirects - Support fast redirects
+net-proxy/privoxy:force - Allow single-page disable (force load)
+net-proxy/privoxy:graceful-termination - Allow to shutdown Privoxy through the webinterface
+net-proxy/privoxy:ie-images - Enable a quick but not always reliable auto-detect whether requests from MS Internet Explorer are for an image or not
+net-proxy/privoxy:image-blocking - Allows the +handle-as-image action, to send "blocked" images instead of HTML
+net-proxy/privoxy:lfs - Support large files (>2GB) on 32-bit systems
+net-proxy/privoxy:png-images - Use PNG format instead of GIF for built-in images
+net-proxy/privoxy:stats - Keep statistics
+net-proxy/privoxy:toggle - Support temporary disable toggle via web interface
+net-proxy/privoxy:tools - Install log parser, regression tester and user agent generator tools
+net-proxy/privoxy:whitelists - Support trust files (white lists)
+net-proxy/privoxy:zlib - Use sys-libs/zlib to decompress data before filtering
+net-proxy/rejik:banlists - Install upstream provided simple banlists
+net-proxy/squid:ecap - Adds support for loadable content adaptation modules (http://www.e-cap.org)
+net-proxy/squid:esi - Enable ESI for accelerators, will cause squid reverse proxies to be capable of the Edge Acceleration Specification (www.esi.org)
+net-proxy/squid:htcp - Enable HTCP protocol
+net-proxy/squid:ipf-transparent - Adds transparent proxy support for systems using IP-Filter (only for *bsd)
+net-proxy/squid:kqueue - Enables *BSD kqueue() support
+net-proxy/squid:logrotate - Use app-admin/logrotate for rotating logs
+net-proxy/squid:pf-transparent - Adds transparent proxy support for systems using PF (only for *bsd)
+net-proxy/squid:qos - Adds support for Quality of Service using netfilter conntrack - see qos_flow directive for more info
+net-proxy/squid:ssl-crtd - Adds support for dynamic SSL certificate generation in SslBump environments
+net-proxy/squid:tproxy - Enables real Transparent Proxy support for Linux Netfilter TPROXY
+net-proxy/squid:wccp - Enable Web Cache Coordination Protocol
+net-proxy/squid:wccpv2 - Enable Web Cache Coordination V2 Protocol
+net-proxy/tinyproxy:filter-proxy - Enable filtering of domains/URLS
+net-proxy/tinyproxy:reverse-proxy - Enable reverse proxying
+net-proxy/tinyproxy:transparent-proxy - Enable transparent proxying
+net-proxy/tinyproxy:upstream-proxy - Enable upstream proxying
+net-proxy/tinyproxy:xtinyproxy-header - Include the X-Tinyproxy header
+net-proxy/tsocks:dns - Force DNS queries to use SOCKS server via tcp
+net-proxy/tsocks:envconf - Allow TSOCKS_CONF_FILE to specify configuration file
+net-proxy/tsocks:server-lookups - Allow hostname resolution _for_ SOCKS servers
+net-proxy/tsocks:tordns - Apply tordns patch which allows transparent TORification of the DNS queries
+net-proxy/ufdbguard:doc - Download and install the ufdbguard reference manual in PDF.
+net-proxy/ufdbguard:httpd - Build, install and start the provided mini-http daemon with the redirect CGI integrated. Since there is no way to tell ufdbguard to not start it, this is a build-time option.
+net-voip/linphone:assistant - Turn on assistant compiling (needs gtk enabled)
+net-voip/linphone:gsm-nonstandard - Support non-standard GSM frequencies
+net-voip/linphone:sqlite - Turn on compilation of message storage
+net-voip/linphone:tools - Compile tools
+net-voip/linphone:video - Enable video support (display/capture)
+net-voip/telepathy-gabble:plugins - Enable plugin loader
+net-voip/yate:amrnb - use AMR-NB
+net-voip/yate:dahdi - Enable Dahdi driver
+net-voip/yate:gsm - use GSM codec
+net-voip/yate:ilbc - Enable iLBC codec
+net-voip/yate:ilbc-webrtc - Enable iLBC webrtc codec
+net-voip/yate:isac-fixed - Enable iSAC fixed codec
+net-voip/yate:isac-float - Enable iSAC float codec
+net-voip/yate:mysql - use MySQL client library
+net-voip/yate:postgres - use Postgress SQL
+net-voip/yate:spandsp - use spandsp library
+net-voip/yate:speex - use Speex codec
+net-voip/yate:tdmcard - Enable TDMV API card driver
+net-voip/yate:wanpipe - Enable Wanpipe support
+net-voip/yate:wpcard - Enable Wanpipe card driver
+net-voip/yate:zaptel - Enable Zaptel driver
+net-vpn/badvpn:client - Build the badvpn-client program, a daemon that runs on endpoints of the VPN.
+net-vpn/badvpn:ncd - Build NCD, a lightweight scripting language especially suited for network configurations.
+net-vpn/badvpn:server - Build the badvpn-server program, a central server that manages the VPN network.
+net-vpn/badvpn:tun2socks - Build tun2socks, a program which implements a TUN device that forwards TCP traffic through a SOCKS5 server.
+net-vpn/badvpn:udpgw - Build udpgw, a small daemon which allows tun2socks to forward UDP traffic.
+net-vpn/i2p:ecdsa - Enables additional checks to make sure a setup is available that is capable of using I2Ps ECDSA provisions. I2P will work without it, but you will likely see warnings.
+net-vpn/i2p:nls - Adds Native Language Support using GNU gettext.
+net-vpn/i2pd:i2p-hardening - Compile with hardening on vanilla compilers/linkers
+net-vpn/i2pd:websocket - Enable websocket server
+net-vpn/ipsec-tools:hybrid - Makes available both mode-cfg and xauth support
+net-vpn/ipsec-tools:idea - Enable support for the IDEA algorithm
+net-vpn/ipsec-tools:nat - Enable NAT-Traversal
+net-vpn/ipsec-tools:rc5 - Enable support for the patented RC5 algorithm
+net-vpn/ipsec-tools:stats - Enable statistics reporting
+net-vpn/libreswan:dnssec - Use DNSSEC resolver (requires net-dns/unbound)
+net-vpn/openconnect:gssapi - Build GSSAPI support
+net-vpn/openconnect:java - Build JNI bindings using jni.h
+net-vpn/openconnect:libproxy - Enable proxy support
+net-vpn/openconnect:lz4 - Enable support for lz4 compression
+net-vpn/openconnect:stoken - Enable stoken support
+net-vpn/openvpn:down-root - Enable the down-root plugin
+net-vpn/openvpn:iproute2 - Enabled iproute2 support instead of net-tools
+net-vpn/openvpn:lz4 - Enable LZ4 support
+net-vpn/openvpn:mbedtls - Use mbed TLS instead of OpenSSL
+net-vpn/openvpn:pkcs11 - Enable PKCS#11 smartcard support
+net-vpn/openvpn:plugins - Enable the OpenVPN plugin system
+net-vpn/pptpd:gre-extreme-debug - Log all GRE accepted packages when in debug mode (required if you want upstream support)
+net-vpn/strongswan:constraints - Enable advanced X.509 constraint checking plugin
+net-vpn/strongswan:dhcp - Enable server support for querying virtual IP addresses for clients from a DHCP server. (IKEv2 only)
+net-vpn/strongswan:eap - Enable support for the different EAP modules that are supported
+net-vpn/strongswan:farp - Enable faking of ARP responses for virtual IP addresses assigned to clients (IKEv2 only)
+net-vpn/strongswan:gcrypt - Enable dev-libs/libgcrypt plugin which provides 3DES, AES, Blowfish, Camellia, CAST, DES, Serpent and Twofish ciphers along with MD4, MD5 and SHA1/2 hash algorithms, RSA and DH groups 1,2,5,14-18 and 22-24(4.4+). Also includes a software random number generator.
+net-vpn/strongswan:non-root - Force IKEv1/IKEv2 daemons to normal user privileges. This might impose some restrictions mainly to the IKEv1 daemon. Disable only if you really require superuser privileges.
+net-vpn/strongswan:openssl - Enable dev-libs/openssl plugin which is required for Elliptic Curve Cryptography (DH groups 19-21,25,26) and ECDSA. Also provides 3DES, AES, Blowfish, Camellia, CAST, DES, IDEA and RC5 ciphers along with MD2, MD4, MD5 and SHA1/2 hash algorithms, RSA and DH groups 1,2,5,14-18 and 22-24(4.4+) dev-libs/openssl has to be compiled with USE="-bindist".
+net-vpn/strongswan:pkcs11 - Enable pkcs11 support
+net-vpn/strongswan:strongswan_plugins_blowfish - Enable support for the blowfish plugin
+net-vpn/strongswan:strongswan_plugins_ccm - Enable support for the ccm plugin
+net-vpn/strongswan:strongswan_plugins_ctr - Enable support for the ctr plugin
+net-vpn/strongswan:strongswan_plugins_gcm - Enable support for the gcm plugin
+net-vpn/strongswan:strongswan_plugins_ha - Enable support for the ha plugin
+net-vpn/strongswan:strongswan_plugins_ipseckey - Enable support for the ipseckey plugin
+net-vpn/strongswan:strongswan_plugins_led - Enable support for the led plugin
+net-vpn/strongswan:strongswan_plugins_lookip - Enable support for the lookip plugin
+net-vpn/strongswan:strongswan_plugins_ntru - Enable support for the ntru plugin
+net-vpn/strongswan:strongswan_plugins_padlock - Enable support for the padlock plugin
+net-vpn/strongswan:strongswan_plugins_rdrand - Enable support for the rdrand plugin
+net-vpn/strongswan:strongswan_plugins_systime-fix - Enable support for the systime-fix plugin
+net-vpn/strongswan:strongswan_plugins_unbound - Enable support for the unbound plugin
+net-vpn/strongswan:strongswan_plugins_unity - Enable support for the unity plugin
+net-vpn/strongswan:strongswan_plugins_vici - Enable support for the vici plugin
+net-vpn/strongswan:strongswan_plugins_whitelist - Enable support for the whitelist plugin
+net-vpn/tinc:gui - Add GUI support, using dev-python/wxpython
+net-vpn/tinc:uml - Enable support for User Mode Linux Sockets
+net-vpn/tinc:vde - Enable Virtual Distributed Ethernet (VDE) based networking
+net-vpn/tor:scrypt - Use app-crypt/libscrypt for the scrypt algorithm
+net-vpn/tor:tor-hardening - Compile tor with hardening on vanilla compilers/linkers
+net-vpn/tor:web - Build a tor2web service instead of a tor client
+net-vpn/tor:zstd - Use app-arch/zstd for compression
+net-vpn/vpnc:resolvconf - Enable support for DNS managing framework net-dns/openresolv
+net-vpn/wireguard:debug - Enable verbose debug reporting in dmesg of various WireGuard peer and device information.
+net-vpn/wireguard:module - Compile the actual WireGuard kernel module. Most certainly you want this enabled, unless you're doing something strange.
+net-vpn/wireguard:module-src - Install the module source code to /usr/src, in case you like building kernel modules yourself.
+net-vpn/wireguard:tools - Compile the wg(8) tool and related helpers. You probably want this enabled.
+net-wireless/aircrack-ng:airdrop-ng - Build airdrop-ng
+net-wireless/aircrack-ng:airgraph-ng - Build airgraph-ng
+net-wireless/aircrack-ng:experimental - Build the "experimental" tools which may randomly fail to run properly
+net-wireless/aircrack-ng:netlink - Use netlink for channel control instead of WEXT
+net-wireless/aircrack-ng:unstable - Build the "unstable" tools which may randomly fail to run properly
+net-wireless/bladerf:tecla - use libtecla for command line editing, tab completion, and history
+net-wireless/bladerf-fpga:x115 - bitstream for the x115KLE Cyclone IV FPGA bladerf model"
+net-wireless/bladerf-fpga:x40 - bitstream for the x40KLE Cyclone IV FPGA bladerf model"
+net-wireless/blueman:appindicator - Enable usage of dev-libs/libappindicator to export menu options
+net-wireless/blueman:network - Add functionality to setup (host) PAN connections using either net-dns/dnsmasq or net-misc/dhcp
+net-wireless/blueman:thunar - Install the sendto-plugin for xfce-base/thunar
+net-wireless/bluez:deprecated - Build deprecated plugins
+net-wireless/bluez:experimental - Build experimental plugins
+net-wireless/bluez:extra-tools - Install tools that upstream doesn't install on purpose by default. All this tools shouldn't be used. Then, please notify upstream about you still need them to let them know the situation.
+net-wireless/bluez:mesh - Add support for Bluetooth Mesh control application and advertising bearer.
+net-wireless/bluez:obex - Enable OBEX transfer support.
+net-wireless/bluez:test-programs - Install tools for testing of various Bluetooth functions
+net-wireless/bluez:user-session - Allow compatibility with user-session semantics for session bus under systemd
+net-wireless/chirp:radioreference - support downloading data from radioreference.com (premium users only)
+net-wireless/crda:gcrypt - Use libgcrypt instead of openssl for key checking
+net-wireless/gnuradio:analog - enable analog signal processing blocks
+net-wireless/gnuradio:atsc - enable ATSC (HDTV) transmitter and receiver blocks
+net-wireless/gnuradio:audio - enable blocks to connect to audio sources (mic-in) and sinks (speaker-out) ports on a computer
+net-wireless/gnuradio:channels - enable channel mode blocks
+net-wireless/gnuradio:digital - enable digital signal processing blocks
+net-wireless/gnuradio:dtv - enable digital tv signal processing blocks
+net-wireless/gnuradio:fcd - enable Funcube Dongle source block
+net-wireless/gnuradio:fec - enable block for convolutional encoding using the CCSDS standard polynomial ("Voyager")
+net-wireless/gnuradio:filter - enable filter signal processing blocks
+net-wireless/gnuradio:grc - enable GNU Radio Companion graphical tool to design signal processing flow graphs
+net-wireless/gnuradio:log - enable logging to console and files
+net-wireless/gnuradio:noaa - enable NOAA POES HRPT receiver blocks
+net-wireless/gnuradio:pager - enable pager signal processing blocks
+net-wireless/gnuradio:performance-counters - enable block performance counters
+net-wireless/gnuradio:trellis - enable trellis blocks for FSM
+net-wireless/gnuradio:uhd - install UHD source and sink blocks
+net-wireless/gnuradio:utils - install scripts to enable viewing and analysis of files produced by flow graphs
+net-wireless/gnuradio:vocoder - enable blocks for audio voice encoders
+net-wireless/gnuradio:wavelet - enable wavelet signal processing blocks
+net-wireless/gnuradio:zeromq - enable zeromq message passing blocks
+net-wireless/gqrx:gr-audio - Use audio support from net-wireless/gnuradio
+net-wireless/gr-air-modes:fgfs - Support FlightGear
+net-wireless/gr-air-modes:rtlsdr - Build with Realtek RTL2832U (rtlsdr) support
+net-wireless/gr-air-modes:uhd - Build with Ettus Research USRP Hardware Driver support
+net-wireless/gr-baz:armadillo - install MUSIC DOA estimator block
+net-wireless/gr-baz:rtlsdr - install rtlsdr source block
+net-wireless/gr-baz:uhd - install UHD aware blocks
+net-wireless/gr-osmosdr:bladerf - Build with Nuand BladeRF support
+net-wireless/gr-osmosdr:fcd - Build with Funcube Dongle support
+net-wireless/gr-osmosdr:hackrf - Build with Great Scott Gadgets HackRF support
+net-wireless/gr-osmosdr:iqbalance - Enable support for I/Q balancing using gr-iqbal
+net-wireless/gr-osmosdr:mirisdr - Build with Mirics MSi2500 + MSi001 SDR support
+net-wireless/gr-osmosdr:rtlsdr - Build with Realtek RTL2832U (rtlsdr) support
+net-wireless/gr-osmosdr:soapy - Build with SoapySDR support
+net-wireless/gr-osmosdr:uhd - Build with Ettus Research USRP Hardware Driver support
+net-wireless/horst:pcap - Add support for network packet capture via net-libs/libpcap
+net-wireless/hostapd:crda - Add CRDA support
+net-wireless/hostapd:logwatch - Install support files for sys-apps/logwatch
+net-wireless/hostapd:netlink - Adding support for using netlink to create VLANs
+net-wireless/hostapd:sqlite - Adding sqlite support
+net-wireless/hostapd:wps - Add support for Wi-Fi Protected Setup
+net-wireless/kismet:client - Build the ncurses-based user interface
+net-wireless/kismet:pcre - Build with pcre support
+net-wireless/kismet:plugin-autowep - Build the autowep plugin
+net-wireless/kismet:plugin-btscan - Build the btscan plugin
+net-wireless/kismet:plugin-dot15d4 - Build the dot15d4 plugin
+net-wireless/kismet:plugin-ptw - Build the ptw plugin
+net-wireless/kismet:plugin-spectools - Build the spectools plugin. This uses net-wireless/spectools
+net-wireless/kismet:plugin-syslog - Build the syslog plugin.
+net-wireless/kismet:ruby - Build extras which are written in ruby, example plugins and the like.
+net-wireless/kismet:speech - Audio support using app-accessibility/flite
+net-wireless/kismet:suid - Install a setuid root helper binary with limited functionality; this allows running kismet as a normal user, significantly reducing security risks
+net-wireless/neard:tools - build and install extra helper utilities
+net-wireless/openbsc:gprs - Support GPRS via OpenGGSN
+net-wireless/osmocom-bb:transmit - Enable transmission capabilities.
+net-wireless/pyrit:cuda - Enable CUDA support via net-wireless/cpyrit-cuda
+net-wireless/pyrit:opencl - Enable OpenCL support via net-wireless/cpyrit-opencl
+net-wireless/soapy_power:faster - Use sci-libs/scipy to speed up drawing
+net-wireless/soapy_power:fastest - Use dev-python/pyFFTW to speed up drawing to the max
+net-wireless/soapysdr:bladerf - Add support for bladerf hardware
+net-wireless/soapysdr:hackrf - Add support for hackrf hardware
+net-wireless/soapysdr:rtlsdr - Add support for rtlsdr hardware
+net-wireless/soapysdr:uhd - Add support for Ettus USRP hardware
+net-wireless/spectools:debug - Build the raw output client for spectools. (for developers)
+net-wireless/spectools:gtk - Build the gtk-2 based client for spectools
+net-wireless/spectools:ncurses - Build the ncurses based client for spectools
+net-wireless/ubertooth:bluez - use bluez to support clock following and scanning
+net-wireless/ubertooth:specan - Enable the ubertooth spectrum analyzer
+net-wireless/ubertooth:ubertooth1-firmware - Build/install ubertooth1-firmware
+net-wireless/uhd:b100 - support B100 hardware
+net-wireless/uhd:b200 - support B200, B210, B200mini, B205mini hardware
+net-wireless/uhd:e300 - support E300, E310 hardware
+net-wireless/uhd:mpmd - support N300, N310 hardware
+net-wireless/uhd:n230 - support N230 harware
+net-wireless/uhd:octoclock - Octoclock Network Support
+net-wireless/uhd:usrp1 - support USRP1 hardware
+net-wireless/uhd:usrp2 - support USRP2, N200, N210 hardware
+net-wireless/uhd:utils - utilities needed to list, query, calibrate, or update FPGA/Firmware
+net-wireless/uhd:x300 - support X300, X310 hardware
+net-wireless/urh:hackrf - use native backend which directly uses net-libs/libhackrf
+net-wireless/urh:rtlsdr - use native backend which directly uses net-wireless/rtl-sdr
+net-wireless/urh:uhd - use native backend which directly uses net-wireless/uhd
+net-wireless/wepattack:john - Build with app-crypt/johntheripper support
+net-wireless/wireless-tools:multicall - Build the most commonly used tools as one binary
+net-wireless/wpa_supplicant:ap - Add support for access point mode
+net-wireless/wpa_supplicant:eap-sim - Add support for EAP-SIM authentication algorithm
+net-wireless/wpa_supplicant:eapol_test - Build and install eapol_test binary
+net-wireless/wpa_supplicant:fasteap - Add support for FAST-EAP authentication algorithm
+net-wireless/wpa_supplicant:hs2-0 - Add support for 802.11u and Passpoint for HotSpot 2.0
+net-wireless/wpa_supplicant:p2p - Add support for Wi-Fi Direct mode
+net-wireless/wpa_supplicant:privsep - Enable wpa_priv privledge separation binary
+net-wireless/wpa_supplicant:ps3 - Add support for ps3 hypervisor driven gelic wifi
+net-wireless/wpa_supplicant:smartcard - Add support for smartcards
+net-wireless/wpa_supplicant:tdls - Add support for Tunneled Direct Link Setup (802.11z)
+net-wireless/wpa_supplicant:uncommon-eap-types - Add support for GPSK, SAKE, GPSK_SHA256, IKEV2 and EKE
+net-wireless/wpa_supplicant:wimax - Add support for Wimax EAP-PEER authentication algorithm
+net-wireless/wpa_supplicant:wps - Add support for Wi-Fi Protected Setup
+net-wireless/yatebts:bladerf - Build bladeRF transceiver
+net-wireless/yatebts:rad1 - Build RAD1 transceiver
+net-wireless/yatebts:uhd - Build UHD transceiver
+net-wireless/yatebts:usrp1 - Build USRP1 transceiver
+sci-astronomy/casacore:c++11 - Build casacore using the C++11 standard
+sci-astronomy/casacore:data - Installs measures and data (pulls sci-astronomy/casa-data)
+sci-astronomy/cpl:gasgano - Enable support for sci-astronomy/gasgano file organizer
+sci-astronomy/esomidas:libtirpc - Build against net-libs/libtirpc for RPC support
+sci-astronomy/healpix:idl - Install healpix IDL/GDL routines
+sci-astronomy/predict:xforms - Add a "map" client which uses the x11-libs/xforms library for its GUI
+sci-astronomy/predict:xplanet - Project predict data onto world maps generated by x11-misc/xplanet / x11-misc/xearth
+sci-astronomy/psfex:plplot - Build with sci-libs/plplot to allow diagnostic plots during processing
+sci-astronomy/scamp:plplot - Build with sci-libs/plplot to allow diagnostic plots during processing
+sci-astronomy/sextractor:modelfit - Enable profile model fitting, needs sci-libs/atlas and sci-libs/fftw
+sci-astronomy/stellarium:media - Enable sound and video support
+sci-astronomy/stellarium:sound - Enable sound support
+sci-astronomy/stellarium:stars - Install extra star catalogs
+sci-astronomy/wcslib:fits - Enable support for the FITS format through sci-libs/cfitsio
+sci-astronomy/wcslib:pgplot - Builds PGBSOX routines, needs sci-libs/pgplot library
+sci-astronomy/wcslib:tools - Builds and installs extra command line utilities for WCS checking
+sci-biology/abyss:misc-haskell - build abyss-samtobreak tool, pull in haskell toolchain
+sci-biology/bioperl:db - Install sci-biology/bioperl-run
+sci-biology/bioperl:network - Install sci-biology/bioperl-run
+sci-biology/bioperl:run - Install sci-biology/bioperl-run
+sci-biology/bowtie:tbb - Enables building bowtie with the Intel Threading Building Blocks from dev-cpp/tbb. This flag is recommended.
+sci-biology/clustalw-mpi:mpi_njtree - Use MPI (as opposed to serial) code for computing neighbor-joining trees
+sci-biology/clustalw-mpi:static_pairalign - Use static (as opposed to dynamic) scheduling for pair alignments
+sci-biology/exonerate:utils - Install all utilities
+sci-biology/fasttree:double-precision - use double precision instead of single-precision floating point (2x memroy required)
+sci-biology/goby:cpp - Compile C/C++ API
+sci-biology/mcl:blast - Add support for NCBI BLAST data
+sci-biology/plink:R - add support R language
+sci-biology/plink:webcheck - add support for online update checking every time the program starts
+sci-biology/seqan:tools - Build and install SeqAn commandline tools, such as the Yara aligner
+sci-biology/ucsc-genome-browser:server - Install genome browser Web application. If this flag is off, only libraries and utilities from the suite are installed.
+sci-biology/yass:dmalloc - Enable debugging with the dmalloc library
+sci-biology/yass:lowmem - Build for environments with low amounts of memory
+sci-calculators/datamash:openssl - Use dev-libs/openssl for cryptographic features
+sci-calculators/units:units_cur - Install the units_cur python script that updates currencies
+sci-chemistry/PyMca:matplotlib - Support for plotting through matplotlib
+sci-chemistry/apbs:fast - APBS fast mode (experimental)
+sci-chemistry/apbs:fetk - Include support for FeTK
+sci-chemistry/apbs:iapbs - C/C++/Fortran interface
+sci-chemistry/apbs:tools - Install optional tools
+sci-chemistry/avogadro:glsl - Enable glsl features via GLEW.
+sci-chemistry/avogadro2:rpc - Enable RPC server
+sci-chemistry/avogadro2:vtk - include vtk support
+sci-chemistry/ball:cuda - Include cuda support
+sci-chemistry/ball:sql - Include SQL database support
+sci-chemistry/chemtool:emf - EMF export support
+sci-chemistry/cns:aria - Support patch for sci-chemistry/aria
+sci-chemistry/eden:double-precision - More precise calculations at the expense of speed
+sci-chemistry/ghemical:openbabel - Use sci-chemistry/openbabel for file conversions
+sci-chemistry/gromacs:boost - Enable external boost library
+sci-chemistry/gromacs:cuda - Enable cuda non-bonded kernels
+sci-chemistry/gromacs:double-precision - More precise calculations at the expense of speed
+sci-chemistry/gromacs:hwloc - Enable HWLoc lib support
+sci-chemistry/gromacs:make-symlinks - Create symbolic links for pre-5.0 binary names
+sci-chemistry/gromacs:mkl - Use sci-libs/mkl for fft, blas, lapack routines
+sci-chemistry/gromacs:offensive - Enable gromacs partly offensive quotes
+sci-chemistry/gromacs:opencl - Enable opencl non-bonded kernels
+sci-chemistry/gromacs:single-precision - Single precision version of gromacs (default)
+sci-chemistry/gromacs:tng - Enable new trajectory format - tng
+sci-chemistry/gsim:emf - Support for .emf export
+sci-chemistry/jmol:client-only - Install the viewer only, no applet files for httpd
+sci-chemistry/molequeue:client - Build the client application
+sci-chemistry/molequeue:server - Build the serve application
+sci-chemistry/molequeue:zeromq - Build with net-libs/zeromq support
+sci-chemistry/mopac7:gmxmopac7 - Add support library for gromacs
+sci-chemistry/pdb2pqr:opal - Add web interface via opal
+sci-chemistry/pdb2pqr:pdb2pka - Install experimental pdb2pka interface
+sci-chemistry/pymol:web - Install Pymodule needed for web app support
+sci-chemistry/raster3d:gd - libgd support for PNG and JPEG output
+sci-chemistry/vmd:cuda - Use nvidia cuda toolkit for speeding up computations
+sci-chemistry/vmd:gromacs - Add support for TNG file format
+sci-chemistry/vmd:msms - Add support for MSMS SAS calcualtion tool
+sci-chemistry/vmd:povray - Add support for povray raytracer for HQ images
+sci-chemistry/vmd:tachyon - Add support for tachyon raytracer for HQ images
+sci-chemistry/votca-csg:extras - Pull in extra applications from sci-chemistry/votca-csgapps
+sci-chemistry/votca-csg:gromacs - Add support for gromacs file formats through sci-chemistry/gromacs
+sci-chemistry/wxmacmolplt:flash - Add support for flash movie generation using media-libs/ming
+sci-electronics/geda:stroke - enable mouse gesture support
+sci-electronics/gerbv:unit-mm - Set default unit for coordinates in status bar to mm
+sci-electronics/gspiceui:schematics - Use sci-electronics/geda for schematics editing
+sci-electronics/gspiceui:waveform - Use sci-electronics/gwave for waveform display
+sci-electronics/gtkwave:fasttree - Enables experimental Fast SST Tree widget code.
+sci-electronics/gtkwave:fatlines - Renders lines as double width in gtkwave.
+sci-electronics/gtkwave:judy - Enables Judy array support.
+sci-electronics/gtkwave:packed - Enables '#pragma pack' for data arrays (saves memory, costs time).
+sci-electronics/kicad:github - Add github support into PCB editor
+sci-electronics/kicad:i18n - Allow GUI internationalization through l10n_* use flags
+sci-electronics/kicad:minimal - Build only binaries without parts library and examples
+sci-electronics/kicad:python - Enable python scripting support
+sci-electronics/ngspice:shared - Build ngspice as a shared library
+sci-electronics/pcb:gcode - gcode file export
+sci-electronics/pcb:gif - GIF graphics export
+sci-electronics/pcb:jpeg - JPEG graphics export
+sci-electronics/pcb:m4lib-png - Enable creating png previews for the m4 library
+sci-electronics/pcb:nelma - NELMA file export
+sci-electronics/pcb:png - PNG graphics export
+sci-electronics/pcb:tk - Build tcl/tk graphical QFP footprint generator
+sci-electronics/pcb:toporouter - Build toporouter
+sci-electronics/pcb:xrender - Translucent PCB display for Motif/Lesstif GUI
+sci-electronics/pulseview:decode - Enable decoding of protocols while capturing
+sci-electronics/sigrok-cli:decode - Enable decoding of protocols while capturing
+sci-electronics/splat:hires - Builds additional high resolution application 'rfsplat-hd'
+sci-geosciences/gdal-grass:postgres - Include support for dev-db/postgresql
+sci-geosciences/gmt:gdal - Enable sci-libs/gdal library support
+sci-geosciences/gmt:gmtfull - Full resolution bathymetry database
+sci-geosciences/gmt:gmthigh - Add high resolution bathymetry database
+sci-geosciences/gmt:gmttria - Non GNU triangulation method, more efficient
+sci-geosciences/gmt:metric - Use SI (cm) units instead of US (inches) ones
+sci-geosciences/gmt:mex - Enable compilation of mex supplement which requires Octave/Matlab
+sci-geosciences/gmt:octave - Enable octave support
+sci-geosciences/gpsbabel:gui - Enable the graphical user interface (requires dev-qt/qtwebengine)
+sci-geosciences/gpsd:dbus - export gpsd data over dbus connections
+sci-geosciences/gpsd:latency_timing - support latency timing information
+sci-geosciences/gpsd:ntp - Enable net-misc/ntp shared memory interface and PPS kernel support for GPS time
+sci-geosciences/gpsd:shm - export gpsd over shared memory
+sci-geosciences/gpsd:sockets - export gpsd over unix sockets
+sci-geosciences/grass:geos - Use sci-libs/geos for v.buffer and adds extended options to the v.select module
+sci-geosciences/grass:liblas - Include support for LAS and LAZ encoded LiDAR files through sci-geosciences/liblas
+sci-geosciences/grass:opencl - Enable OpenCL support
+sci-geosciences/gshhs:data - Add earth data with sci-geosciences/gshhs-data
+sci-geosciences/liblas:gdal - Add support for the sci-libs/gdal geospatial raster library
+sci-geosciences/mapnik:gdal - Enable sci-libs/gdal library support
+sci-geosciences/mapserver:gdal - Enable sci-libs/gdal library support
+sci-geosciences/mapserver:geos - Enable sci-libs/geos library support
+sci-geosciences/mapserver:postgis - Enable dev-db/postgis support
+sci-geosciences/mapserver:proj - Enable sci-libs/proj library support (geographic projections)
+sci-geosciences/mapserver:xslt - Enable xslt and exslt support xml-mapfile support
+sci-geosciences/merkaartor:libproxy - Use net-libs/libproxy for getting the HTTP/HTTPS/SOCKS proxy configuration
+sci-geosciences/merkaartor:webengine - Enable dev-qt/qtwebengine in some plugins
+sci-geosciences/qgis:3d - Build QGIS 3D library using dev-qt/qt3d
+sci-geosciences/qgis:georeferencer - Determines whether georeferencer plugin should be built
+sci-geosciences/qgis:grass - Add support for sci-geosciences/grass
+sci-geosciences/qgis:mapserver - Determines whether mapserver should be built
+sci-geosciences/qgis:polar - Enable support for the polar coordinate system via x11-libs/qwtpolar
+sci-geosciences/viking:libexif - Use media-libs/libexif for EXIF support
+sci-geosciences/viking:magic - Use libmagic to determine mimetypes
+sci-geosciences/viking:mapnik - Enable a layer based on sci-geosciences/mapnik
+sci-geosciences/viking:sqlite - Enable MBTiles support based on dev-db/sqlite
+sci-geosciences/xtide:gps - Use sci-geosciences/gpsd
+sci-libs/ViSP:coin - Enables Coin3D support.
+sci-libs/ViSP:demos - Installs demo programs.
+sci-libs/ViSP:dmtx - Enables barcode data matrix support.
+sci-libs/ViSP:ogre - Enables dev-games/ogre support.
+sci-libs/ViSP:ois - Enables dev-games/ois support via ogre.
+sci-libs/ViSP:opencv - Enables media-libs/opencv support.
+sci-libs/ViSP:tutorials - Installs tutorials.
+sci-libs/ViSP:zbar - Enables barcodes reading.
+sci-libs/adolc:sparse - Add support for sparse matrix algebra with sci-libs/colpack
+sci-libs/armadillo:arpack - Link with sci-libs/arpack libraries for eigen decomposition
+sci-libs/armadillo:mkl - Use matrix allocation from the Intel MKL sci-libs/mkl
+sci-libs/armadillo:superlu - Use SuperLU for sparse linear equation solving sci-libs/superlu
+sci-libs/armadillo:tbb - Use matrix allocation from the Threads Building Blocks dev-cpp/tbb
+sci-libs/arprec:qd - Use sci-libs/qd for quad-double datatype
+sci-libs/atlas:generic - Build atlas assuming a fairly generic architecture (sse2 for x86, core2 for amd64)
+sci-libs/avogadrolibs:static-plugins - Build all plugins statically into main plugin modules
+sci-libs/avogadrolibs:vtk - include vtk support
+sci-libs/cddlib:tools - Add a few executables and tests for cddlib
+sci-libs/ceres-solver:c++11 - Build ceres-solver using the C++11 standard
+sci-libs/ceres-solver:cxsparse - Enable simple support for sparse matrix algebra from sci-libs/cxsparse with no LAPACK dependencies
+sci-libs/ceres-solver:gflags - Use dev-cpp/gflags for flag parsing
+sci-libs/ceres-solver:schur - Enable fixed-size schur specializations (disable if binary size is an issue)
+sci-libs/ceres-solver:sparse - Enable support for sparse matrix algebra with various packages from SuiteSparse
+sci-libs/cfitsio:tools - Build execs fpack, funpack, imcopy, fitscopy, listhead
+sci-libs/cgnslib:legacy - Enable or disable building legacy code (3.0 compatible)
+sci-libs/cgnslib:tools - A number of utility programs: cgnscheck, cgnscompress, cgnsdiff, cgnslist, cgnsnames, cgnsupdate, cgnsconvert, adf2hdf, hdf2adf.
+sci-libs/cholmod:cuda - Use nvidia cuda toolkit for speeding up computations
+sci-libs/cholmod:metis - Enable the Partition module to cholmod using sci-libs/metis
+sci-libs/clblas:client - Build a command line clBLAS client program.
+sci-libs/clblas:ktest - A command line tool for testing single clBLAS kernel.
+sci-libs/clblas:performance - Copy performance scripts that can measure and graph performance.
+sci-libs/clblast:client - Enable compilation of the clients to test and compare performance with reference libraries
+sci-libs/coinor-bonmin:glpk - Undocumented USE
+sci-libs/coinor-clp:glpk - Enable GNU Linear Programming Kit sci-mathematics/glpk support
+sci-libs/coinor-clp:metis - Enable partitioning with sci-libs/metis
+sci-libs/coinor-clp:mumps - Enable sci-libs/mumps support
+sci-libs/coinor-clp:sparse - Enable support for sparse matrix with sci-libs/cholmod
+sci-libs/coinor-osi:glpk - Enable GNU Linear Programming Kit sci-mathematics/glpk support
+sci-libs/coinor-symphony:glpk - Enable GNU Linear Programming Kit sci-mathematics/glpk support
+sci-libs/coinor-utils:glpk - Enable GNU Linear Programming Kit sci-mathematics/glpk support
+sci-libs/dlib:cblas - Build with CBLAS virtual/cblas
+sci-libs/dlib:cuda - Enable support for CUDA for Deep Neural Networks (cuDNN) on GPU (experimental)
+sci-libs/dlib:mkl - Enable support for Intel FFT sci-libs/mkl
+sci-libs/dmlc-core:s3 - Support for the Amazon Simple Storage Service
+sci-libs/fftw:float - Link default library to single precision instead of double (symlinks only and fftw-2.1)
+sci-libs/fftw:quad - Build quadruple precision lib
+sci-libs/fftw:zbus - Adds support for ZBus cycle-counter of mips
+sci-libs/flann:cuda - Enable support for nVidia CUDA
+sci-libs/flann:octave - Add bindings for sci-mathematics/octave
+sci-libs/gdal:armadillo - Use sci-libs/armadillo for faster TPS transform computation
+sci-libs/gdal:aux_xml - Enable Portable Auxilliary Metadata generation
+sci-libs/gdal:fits - Enable support for NASA's sci-libs/cfitsio library
+sci-libs/gdal:geos - Add support for geometry engine (sci-libs/geos)
+sci-libs/gdal:gml - Enable support for dev-libs/xerces-c C++ API
+sci-libs/gdal:hdf5 - Add support for the Hierarchical Data Format v5 (sci-libs/hdf5)
+sci-libs/gdal:mdb - Enable support for Microsoft Access database
+sci-libs/gdal:ogdi - Enable support for the open geographic datastore interface (sci-libs/ogdi)
+sci-libs/gdal:opencl - Enable OpenCL support
+sci-libs/gdal:spatialite - Enable Spatial DBMS over sqlite dev-db/spatialite
+sci-libs/gdal:xls - Add the dev-libs/freexl library for xls import support
+sci-libs/grib_api:aec - Build with Adaptive Entropy Coding compression, needs sci-libs/libaec
+sci-libs/grib_api:jasper - Use media-libs/jasper instead of media-libs/openjpeg for JPEG 2000 support
+sci-libs/gsl:cblas-external - Link gsl with external cblas provided by (virtual/cblas) instead of shipped internal version
+sci-libs/gsl:deprecated - Enable deprecated functions
+sci-libs/hdf5:fortran2003 - Enable new features that require Fortran 2003 (http://www.hdfgroup.org/HDF5/doc/fortran/NewFeatures_F2003.pdf)
+sci-libs/hdf5:hl - Enable high level API (https://support.hdfgroup.org/HDF5/doc/HL/index.html)
+sci-libs/hypre:fei - Build the internal Finite Element Interface routines
+sci-libs/hypre:int64 - Build the 64 bits integer library
+sci-libs/ipopt:hsl - hsl
+sci-libs/ipopt:mumps - Enable sci-libs/mumps support
+sci-libs/lapack-reference:deprecated - Build deprecated routines
+sci-libs/lemon:coin - Enable the sci-libs/coinor-clp and sci-libs/coinor-cbc graph algorithms
+sci-libs/lemon:glpk - Enable GNU Linear Programming Kit sci-mathematics/glpk support
+sci-libs/lemon:tools - Build additional tools
+sci-libs/libccd:double - Use double precision floats.
+sci-libs/libghemical:mopac7 - Use sci-chemistry/mopac7 for semi-empirical calculations
+sci-libs/libghemical:mpqc - Use sci-chemistry/mpqc for quantum-mechanical calculations
+sci-libs/libsc:romio - Build with support for the ROMIO MPI-IO component
+sci-libs/libsigrok:ftdi - Enable drivers that need libftdi
+sci-libs/libsigrok:parport - Enable drivers that are parallel (IEEE1284) based
+sci-libs/libsigrok:serial - Enable drivers that are serial (RS232) based
+sci-libs/libsvm:tools - Install python based tool scripts for data selection and visualization with sci-visualization/gnuplot
+sci-libs/linux-gpib:firmware - Install firmware
+sci-libs/linux-gpib:isa - Build ISA kernel modules; from 3.12 on the setting is ignored and the decision based on the kernel configuration
+sci-libs/lis:quad - Enable quadruple precision operations
+sci-libs/lis:saamg - Build the Smoothed Aggregation Algebraic MultiGrid preconditioner
+sci-libs/magma:fermi - Compile for GPU NVIDIA Fermi family (2.x cards)
+sci-libs/magma:kepler - Compile for GPU NVIDIA Kepler family (GF 6xx cards)
+sci-libs/mathgl:hdf - Add support for the Hierarchical Data Format v.4 sci-libs/hdf
+sci-libs/mathgl:octave - Add bindings for sci-mathematics/octave
+sci-libs/matio:sparse - Extend formats for sparse matrix (not matlab)
+sci-libs/mkl:fortran95 - Installs the BLAS/LAPACK FORTRAN95 static libraries
+sci-libs/mkl:int64 - Installs the 64 bits integer libraries
+sci-libs/mpir:cpudetection - Enables runtime cpudetection (useful for bindist, compatability on other CPUs)
+sci-libs/mumps:metis - Enable matrix ordering with METIS (sci-libs/metis, sci-libs/parmetis)
+sci-libs/mumps:scotch - Enable matrix ordering with sci-libs/scotch
+sci-libs/netcdf:dap - Support for remote data access with the built-in OPeNDAP client
+sci-libs/netcdf:hdf - Add support for the Hierarchical Data Format v.4 sci-libs/hdf
+sci-libs/netcdf:tools - Build the utilities nccopy, ncgen and ncdump
+sci-libs/nlopt:octave - Add plugin for sci-mathematics/octave
+sci-libs/o2scl:armadillo - Build matrix manipulation with sci-libs/armadillo
+sci-libs/o2scl:eigen - Build matrix manipulation with dev-cpp/eigen
+sci-libs/octomap:dynamicEDT3D - Build and install dynamicEDT3D library: A library for incrementally updatable Euclidean distance transforms in 3D.
+sci-libs/opencascade:freeimage - Enable support for image i/o via media-libs/freeimage
+sci-libs/opencascade:gl2ps - Use gl2ps PostScript printing library
+sci-libs/opencascade:tbb - Enable multithreading with the Intel Threads Building Block dev-cpp/tbb
+sci-libs/opencascade:vtk - Enable Virtualisation Toolkit
+sci-libs/openfoam:opendx - Install opendx visualisation tool
+sci-libs/openfoam:paraview - Enable support for paraview library
+sci-libs/openfoam:src - Install source files
+sci-libs/orocos_kdl:models - Build models for some well known robots.
+sci-libs/p4est:romio - Build with support for the ROMIO MPI-IO component
+sci-libs/p4est:vtk-binary - Enable binary vtk output. If disabled vtk files will be written in ASCII text format.
+sci-libs/pastix:int64 - Build the 64 bits integer library
+sci-libs/pastix:starpu - Build and link with dev-libs/starpu
+sci-libs/pcl:cuda - Adds support for NVIDIA CUDA.
+sci-libs/pcl:openni - Adds support for Kinect-like 3D sensors devices with dev-libs/OpenNI.
+sci-libs/pcl:openni2 - Adds support for Kinect-like 3D sensors devices with dev-libs/OpenNI2 (should be preferred over openni).
+sci-libs/pcl:pcap - Adds pcap file capabilities in some drivers.
+sci-libs/pcl:qhull - Adds convex-hull operation support via media-libs/qhull.
+sci-libs/pcl:tutorials - Builds and installs tutorials.
+sci-libs/pcl:vtk - Adds support for VTK-Visualizations.
+sci-libs/plplot:dynamic - Build with dynamic drivers
+sci-libs/plplot:octave - Add bindings for sci-mathematics/octave
+sci-libs/plplot:pdl - Add bindings for dev-perl/PDL
+sci-libs/plplot:qhull - Add bindings for media-libs/qhull
+sci-libs/plplot:shapefile - Enable support for ESRI shapefiles
+sci-libs/rtabmap:openni2 - Adds support for Kinect-like 3D sensors devices with dev-libs/OpenNI2.
+sci-libs/scikits_image:freeimage - Enable support for image i/o via media-libs/freeimage
+sci-libs/scikits_image:pyamg - Enable support for algebraic solvers via dev-python/pyamg
+sci-libs/scipy:sparse - Adds support for sparse solving with sci-libs/umfpack
+sci-libs/scotch:int64 - Build the 64 bits integer library (needed for > 2^31 vertices)
+sci-libs/scotch:tools - Build and install extra exec tools
+sci-libs/shogun:R - Enable support for dev-lang/R
+sci-libs/shogun:octave - Enable support for sci-mathematics/octave
+sci-libs/shogun:opencl - Enable support for building against OpenCL
+sci-libs/silo:silex - Build silex data browser
+sci-libs/spqr:metis - Use sci-libs/metis or sci-libs/parmetis for partitioning
+sci-libs/spqr:tbb - Enable multithreading with the Intel Threads Building Block dev-cpp/tbb
+sci-libs/spr:root - Add sci-physics/root graphics and i/o support
+sci-libs/ssm:ccp4 - Link superpose with libccp4
+sci-libs/suitesparse:cuda - Enable nvidia cuda toolkit for speeding up computations
+sci-libs/suitesparse:metis - Enable the Partition module to cholmod using sci-libs/metis
+sci-libs/suitesparse:tbb - Enable multithreading with the Intel Threads Building Block dev-cpp/tbb
+sci-libs/sundials:hypre - Build with sci-libs/hypre conditioners
+sci-libs/sundials:sparse - Enable support for sci-libs/klu sparse solver
+sci-libs/sundials:superlumt - Build with sci-libs/superlu_mt
+sci-libs/superlu_mt:int64 - Build the 64 bits integer library
+sci-libs/symengine:arb - Add support for arb (sci-mathematics/arb)
+sci-libs/symengine:benchmarks - Build benchmarks
+sci-libs/symengine:boost - Add support for boost integers(dev-libs/boost)
+sci-libs/symengine:flint - Add support for (sci-mathematics/flint)
+sci-libs/symengine:llvm - Build with LLVM
+sci-libs/symengine:mpc - Add support for multiprecision complex arithmetic(dev-libs/mpc)
+sci-libs/symengine:mpfr - Add support for multiprecision floating point rouding(dev-libs/mpfr)
+sci-libs/taucs:cilk - Enable multithreading using dev-lang/cilk
+sci-libs/umfpack:cholmod - Use sci-libs/cholmod for matrix ordering
+sci-libs/vtk:R - Enable support for dev-lang/R
+sci-libs/vtk:all-modules - Build all modules
+sci-libs/vtk:boost - Add support for boost
+sci-libs/vtk:cg - Use nvidia's cg shaders
+sci-libs/vtk:gdal - Support for gdal formated data
+sci-libs/vtk:imaging - Building Imaging modules
+sci-libs/vtk:json - Support for json formated data
+sci-libs/vtk:kaapi - Use sci-libs/xkaapi to handle smp support
+sci-libs/vtk:offscreen - Offscreen rendering through OSMesa
+sci-libs/vtk:rendering - Building Redering modules
+sci-libs/vtk:tbb - Use dev-cpp/tbb to handle smp support
+sci-libs/vtk:views - Building Views modules
+sci-libs/vtk:web - Install web component
+sci-libs/vtk:xdmf2 - Support for xdmf2 formated data
+sci-libs/xkaapi:blas - Kaapi BLAS tasks for PLASMA
+sci-libs/xkaapi:gpu - Build library for gpu threading
+sci-mathematics/Macaulay2:optimization - Accept upstream's choices for -O option, i.e. -O3 almost everywhere.
+sci-mathematics/agda:cpphs - Use cpphs instead of cpp.
+sci-mathematics/agda:stdlib - Install the standard library.
+sci-mathematics/agda:uhc - Add support for the uhc backend.
+sci-mathematics/agda-stdlib:ffi - Install agda-lib-ffi for compilation using the MAlonzo backend
+sci-mathematics/bertini:optimization - Accept upstream's choices for -O option.
+sci-mathematics/cgal:mpfi - Enable support for multiple recision interval arithmetic via sci-libs/mpfi
+sci-mathematics/cgal:ntl - Enable support for dev-libs/ntl
+sci-mathematics/coq:camlp5 - Build using camlp5. This is required for some plugins like Ssreflect.
+sci-mathematics/cvc3:isabelle - Add integration support for the Isabelle/HOL theorem prover.
+sci-mathematics/cvc3:zchaff - Use the SAT solver zchaff whose copyright is owned by Princeton University and is more restrictive (see zchaff license).
+sci-mathematics/e:isabelle - Add integration support for the Isabelle/HOL theorem prover.
+sci-mathematics/flint:gc - Enable garbage collection support via dev-libs/boehm-gc
+sci-mathematics/flint:ntl - Build NTL interface
+sci-mathematics/form:devref - Build and install developers reference
+sci-mathematics/form:doxygen - Build and install API documentation
+sci-mathematics/fricas:clisp - Add support for GNU CLISP (dev-lisp/clisp)
+sci-mathematics/fricas:clozurecl - Add support for Clozure Common Lisp (dev-lisp/clozurecl)
+sci-mathematics/fricas:cmucl - Add support for CMU Common Lisp (dev-lisp/cmucl)
+sci-mathematics/fricas:ecls - Add support for Embeddable Common Lisp (dev-lisp/ecls)
+sci-mathematics/fricas:gcl - Add support for GNU Common Lisp (dev-lisp/gcl)
+sci-mathematics/fricas:sbcl - Add support for Steel Bank Common Lisp (dev-lisp/sbcl)
+sci-mathematics/geomview:motionaveraging - Enable experimental motion averaging technique
+sci-mathematics/gmp-ecm:custom-tune - Improve performance of some operations by selecting machine-specific defaults
+sci-mathematics/gmp-ecm:gwnum - Use GWNum lib where possible
+sci-mathematics/gretl:R - Enable support for dev-lang/R
+sci-mathematics/gsl-shell:fox - Build a x11-libs/fox GUI
+sci-mathematics/isabelle:graphbrowsing - Generate theory browsing information, including HTML documents that show a theory's definition, the theorems proved in its ML file and the relationship with its ancestors and descendants.
+sci-mathematics/isabelle:ledit - Use ledit for the isabelle tty line editor
+sci-mathematics/isabelle:readline - Use readline (rlwrap) for the isabelle tty line editor
+sci-mathematics/kodkodi:isabelle - Add integration support for the Isabelle/HOL theorem prover.
+sci-mathematics/maxima:clisp - Compile maxima with GNU CLISP (dev-lisp/clisp)
+sci-mathematics/maxima:clozurecl - Compile maxima with Clozure Common Lisp (dev-lisp/clozurecl)
+sci-mathematics/maxima:cmucl - Compile maxima with CMU Common Lisp (dev-lisp/cmucl)
+sci-mathematics/maxima:ecls - Compile maxima with Embeddable Common Lisp (dev-lisp/ecls)
+sci-mathematics/maxima:gcl - Compile maxima with GNU Common Lisp (dev-lisp/gcl)
+sci-mathematics/maxima:sbcl - Compile maxima with Steel Bank Common Lisp (dev-lisp/sbcl)
+sci-mathematics/minisat:extended-solver - Build extended version of SAT solver with additional features.
+sci-mathematics/msieve:ecm - Enable support for the GMP-ECM library
+sci-mathematics/normaliz:extras - Install sci-mathematics/Macaulay2 and sci-mathematics/singularpackages as shipped by upstream
+sci-mathematics/nusmv:minisat - Enable support for MiniSat
+sci-mathematics/nusmv:zchaff - Enable support for zChaff
+sci-mathematics/octave:glpk - Add support for sci-mathematics/glpk for linear programming
+sci-mathematics/octave:gui - Enable the graphical user interface
+sci-mathematics/octave:openssl - Use dev-libs/openssl for low level hash functions
+sci-mathematics/octave:qhull - Add support for media-libs/qhull, to allow `delaunay', `convhull', and related functions
+sci-mathematics/octave:qrupdate - Add support for sci-libs/qrupdatefor QR and Cholesky update functions
+sci-mathematics/octave:sparse - Add enhanced support for sparse matrix algebra with SuiteSparse
+sci-mathematics/pari:data - Add additional data (elldata, galdata, seadata, nftables)
+sci-mathematics/polymake:bliss - Enable sci-libs/bliss interface for graph and face lattice isomorphism computations.
+sci-mathematics/polymake:cdd - Enable sci-libs/cddlib interface for convex hull computations (Should be kept enabled).
+sci-mathematics/polymake:group - Build extension for dealing with permutation groups and symmetric objects.
+sci-mathematics/polymake:libnormaliz - Build the bundled extension for lattice related computations.
+sci-mathematics/polymake:libpolymake - Build the polymake library to build applications using the C++ interface.
+sci-mathematics/polymake:lrs - Enable sci-libs/lrslib interface for convex hull computations.
+sci-mathematics/polymake:ppl - Enable dev-libs/ppl interface for convex hull computations.
+sci-mathematics/polymake:singular - Enable the interface to sci-mathematics/singular for ideal related computations.
+sci-mathematics/rstudio:server - Build and install the RStudio server
+sci-mathematics/rw:executable - Build the 'rw' program.
+sci-mathematics/singular:boost - Compile against external boost headers (dev-libs/boost)
+sci-mathematics/spass:isabelle - Add integration support for the Isabelle/HOL theorem prover.
+sci-mathematics/unuran:prng - Use sci-mathematics/prng library
+sci-mathematics/unuran:rngstreams - Use sci-mathematics/rngstreams library
+sci-mathematics/why3-for-spark:coq - Add sci-mathematics/coq support
+sci-mathematics/why3-for-spark:html - Build HTML documentation
+sci-mathematics/why3-for-spark:hypothesis-selection - Enable hypothesis selection
+sci-mathematics/why3-for-spark:profiling - Enable profiling
+sci-mathematics/why3-for-spark:zarith - Use dev-ml/zarith
+sci-mathematics/why3-for-spark:zip - Enable compression of session files
+sci-mathematics/yacas:doc - Generate HTML documentation
+sci-mathematics/yacas:gui - Build graphical interface for the native yacas engine. Requires Qt5
+sci-mathematics/yacas:java - Build the Java yacas engine and text console for it
+sci-mathematics/yacas:jupyter - Add support for jupyter notebook
+sci-mathematics/yafu:sieve - Use msieve for the sieving steps of NFS
+sci-mathematics/z3:isabelle - Add integration support for the Isabelle/HOL theorem prover.
+sci-misc/boinc:cuda - Use nvidia cuda toolkit for speeding up computations. NOTE: works only for subset of nvidia graphic cards so make sure your card is supported before opening a bug about it.
+sci-misc/h5utils:hdf - Build hdf to hdf5 (and vice-versa) converter
+sci-misc/h5utils:octave - Build Octave plugins
+sci-misc/nco:dap - Support for remote data access with the NETCDF DAP client
+sci-misc/nco:ncap2 - Build next generation netcdf arithmetic processor (needs dev-java/antlr)
+sci-misc/nco:udunits - Add sci-libs/udunits files support
+sci-physics/bullet:bullet3 - Build Bullet 3
+sci-physics/bullet:double-precision - Build libraries in double precision
+sci-physics/bullet:extras - Build additional libraries
+sci-physics/cernlib-montecarlo:herwig - Build Herwig internal event generator, newer version available in sci-physics/herwig
+sci-physics/espresso:cuda - Enable cuda support
+sci-physics/espresso:examples - Installs the examples
+sci-physics/espresso:packages - Installs extra TCL subpackages
+sci-physics/fastjet:cgal - Use sci-mathematics/cgal instead of bundled algorithms
+sci-physics/fastjet:plugins - Build all standard and C++ plugins
+sci-physics/geant:data - Add a lot of standard physics data files for geant4
+sci-physics/geant:dawn - Add support for media-gfx/dawn (3D postscript rendering)
+sci-physics/geant:gdml - Enable geometry markup language for xml
+sci-physics/geant:geant3 - Add compatibility for geant321 to geant4
+sci-physics/geant:inventor - Add support for Open Inventor SGI toolkit via Coin3D
+sci-physics/geant:raytracerx - Enable raytracing for physics events
+sci-physics/geant:vrml - Enable output of geant4 in vrml formats
+sci-physics/hepmc:cm - Build with cm instead of default mm for length units
+sci-physics/hepmc:gev - Build with GeV instead of default MeV for momentum units
+sci-physics/herwig++:c++11 - Build Herwig++ using the C++11 standard. Experimental feature, not for production use.
+sci-physics/herwig++:fastjet - Adds support for sci-physics/fastjet
+sci-physics/hoomd-blue:cuda - Enable cuda non-bonded kernels
+sci-physics/lammps:cuda - Enable cuda non-bonded kernels
+sci-physics/lammps:lammps-memalign - Enables the use of the posix_memalign() call instead of malloc() when large chunks or memory are allocated by LAMMPS. Aliengnment is on 16 byte boundaries.
+sci-physics/lhapdf:octave - Add bindings for sci-mathematics/octave
+sci-physics/pythia:fastjet - Build jets using the sci-physics/fastjet package
+sci-physics/pythia:hepmc - Adds support for High Energy Physics Monte Carlo Generators sci-physics/hepmc
+sci-physics/pythia:lhapdf - Support the use of external PDF sets via sci-physics/lhapdf
+sci-physics/pythia:root - Use sci-physics/root trees and histograms (in examples only)
+sci-physics/root:R - Enable support for dev-lang/R
+sci-physics/root:asimage - Enable support for media-libs/libafterimage
+sci-physics/root:c++11 - Build ROOT using the C++11 standard
+sci-physics/root:c++14 - Build ROOT using the C++14 standard
+sci-physics/root:davix - Enable support for DAVIX Data Management Client (https://cern.ch/davix)
+sci-physics/root:fits - Enable support for images and data from FITS files with sci-libs/cfitsio
+sci-physics/root:fortran - Compile included Fortran programs
+sci-physics/root:gdml - Enable GDML writer and reader
+sci-physics/root:http - Enable http server support including but not limited to fastcgi support
+sci-physics/root:jemalloc - Enable support for dev-libs/jemalloc
+sci-physics/root:libcxx - Build ROOT against sys-libs/libcxx
+sci-physics/root:math - Build all math related libraries plugins, needs sci-libs/gsl
+sci-physics/root:memstat - Build memory statistics library, helps to detect memory leaks
+sci-physics/root:minuit - Build ROOT's internal versions of minuit (fortran) and minuit2 (C++)
+sci-physics/root:pythia6 - Build the interface for sci-physics/pythia version 6.x
+sci-physics/root:pythia8 - Build the interface for sci-physics/pythia version 8.x
+sci-physics/root:reflex - Build the reflection database for the C++ interpreter
+sci-physics/root:roofit - Build RooFit function fitting package
+sci-physics/root:root7 - Build experimental features to be released with ROOT 7
+sci-physics/root:shadow - Enable shadow authentication in rootd and proofd
+sci-physics/root:table - Build libTable contrib library
+sci-physics/root:tbb - Enable implicit multi-threading (IMT) with dev-cpp/tbb
+sci-physics/root:tmva - Built TMVA (ROOT's multi-variate analysis toolkit for machine learning)
+sci-physics/root:unuran - Enable support for sci-mathematics/unuran
+sci-physics/root:vc - Enable support for dev-libs/vc with VecCore
+sci-physics/root:xrootd - Build the interface for net-libs/xrootd
+sci-physics/thepeg:c++11 - Build ThePEG using the C++11 standard. Experimental feature, not for production use.
+sci-physics/thepeg:fastjet - Adds support for sci-physics/fastjet
+sci-physics/thepeg:hepmc - Adds support for High Energy Physics Monte Carlo Generators sci-physics/hepmc
+sci-physics/thepeg:lhapdf - Adds support for sci-physics/lhapdf
+sci-physics/thepeg:rivet - Adds support for sci-physics/rivet
+sci-physics/vgm:geant4 - Enable interaction with Geant4(sci-physics/geant:4)
+sci-physics/vgm:root - Enable interaction with ROOT (sci-physics/root)
+sci-physics/yoda:root - Adds support for sci-physics/root
+sci-visualization/fityk:nlopt - Enable optimization with sci-libs/nlopt
+sci-visualization/gnuplot:bitmap - Enable dot-matrix printers and pbm terminal
+sci-visualization/gnuplot:compat - Enable backwards compatibility with version 4 syntax
+sci-visualization/gnuplot:gd - Add support for media-libs/gd. Needed for GIF, JPEG, and PNG image output.
+sci-visualization/gnuplot:libcerf - Enable special functions from sci-libs/libcerf
+sci-visualization/gnuplot:regis - Enable ReGIS terminal
+sci-visualization/gwyddion:fits - Enable FITS image import via sci-libs/cfitsio
+sci-visualization/gwyddion:sourceview - Enable support for x11-libs/gtksourceview
+sci-visualization/labplot:cantor - Enable support for different open-source computer algebra systems via kde-apps/cantor
+sci-visualization/labplot:fits - Enable support for NASA's sci-libs/cfitsio library
+sci-visualization/opendx:cdf - Add support for sci-libs/cdf data exchange format
+sci-visualization/opendx:hdf - Add support for the Hierarchical Data Format (sci-libs/hdf)
+sci-visualization/paraview:boost - Enable the usage of dev-libs/boost
+sci-visualization/paraview:cg - Add support for nvidia's cg shaders
+sci-visualization/paraview:coprocessing - Enable the coprocessing infrastructure which is mainly useful in the context of clusters
+sci-visualization/paraview:development - Install development files including headers
+sci-visualization/paraview:nvcontrol - Add NVCONTROL support for OpenGL options
+sci-visualization/paraview:plugins - Build and install additional plugins
+sci-visualization/veusz:emf - Add FITS format via dev-python/pyemf
+sci-visualization/veusz:fits - Add FITS format via dev-python/astropy
+sci-visualization/veusz:minuit - Use Minuit during fitting viadev-python/pyminuit
+sci-visualization/visit:cgns - Builds the reader for the CFD General Notation System file format.
+sci-visualization/visit:silo - Adds support for reading .silo files.
+sci-visualization/visit:xdmf2 - Support for xdmf2 formated data.
+sci-visualization/yt:hub - Connect to the yt hub with dev-python/girder-client
+sec-policy/selinux-base:open_perms - Enable the open permissions for file object classes (SELinux policy capability).
+sec-policy/selinux-base:peer_perms - Enable the labeled networking peer permissions (SELinux policy capability).
+sec-policy/selinux-base:ubac - Enable User Based Access Control (UBAC) in the SELinux policy
+sec-policy/selinux-base:unconfined - Enable support for the unconfined SELinux module
+sec-policy/selinux-base-policy:unconfined - Enable support for the unconfined SELinux policy module
+sys-apps/accountsservice:elogind - Use sys-auth/elogind instead of sys-auth/consolekit for session tracking
+sys-apps/accountsservice:systemd - Use sys-apps/systemd instead of sys-auth/consolekit for session tracking
+sys-apps/baselayout:usrmerge - Activate the /usr merge when stages are built
+sys-apps/busybox:make-symlinks - Create all the appropriate symlinks in /bin and /sbin.
+sys-apps/busybox:math - Enable math support in gawk (requires libm)
+sys-apps/busybox:mdev - Create the appropriate symlink in /sbin and install mdev.conf and support files
+sys-apps/busybox:sep-usr - Support a separate /usr without needing an initramfs by booting with init=/ginit
+sys-apps/busybox:static - Make the system rescue shell (/bin/bb) static so you can recover even when glibc is broken
+sys-apps/busybox:systemd - Support systemd
+sys-apps/coreutils:caps - Add Linux capabilities support in output of file utilities (ls, dir, ...) via sys-libs/libcap
+sys-apps/coreutils:hostname - Build the hostname program
+sys-apps/coreutils:kill - Build the kill program
+sys-apps/coreutils:multicall - Build all tools into a single `coreutils` program akin to busybox to save space
+sys-apps/dbus:elogind - Use sys-auth/elogind for session tracking.
+sys-apps/dbus:systemd - Build with sys-apps/systemd at_console support
+sys-apps/dbus:user-session - Enable user-session semantics for session bus under systemd
+sys-apps/dbus-broker:launcher - dbus-daemon compatibility launcher
+sys-apps/debianutils:installkernel - Install /sbin/installkernel script (for Linux)
+sys-apps/dstat:wifi - Enable wireless network functions
+sys-apps/duc:X - Use X11 for the GUI instead of OpenGL. This is the recommended option
+sys-apps/duc:cairo - Build support for exporting to PNG and PDF with x11-libs/cairo
+sys-apps/duc:gui - Build support for a graphical client
+sys-apps/duc:leveldb - Use dev-libs/leveldb as the backend
+sys-apps/duc:ncurses - Build support for the ncurses client
+sys-apps/duc:sqlite - Use dev-db/sqlite:3 as the backend
+sys-apps/duc:tokyocabinet - Use dev-db/tokyocabinet as the backend
+sys-apps/elfix:ptpax - Enable PT_PAX_FLAGS support.
+sys-apps/elfix:xtpax - Enable XATTR_PAX_FLAGS support.
+sys-apps/entropy-server:matter - Pull in app-admin/matter
+sys-apps/etckeeper:bazaar - Support dev-vcs/bzr based repository
+sys-apps/etckeeper:cron - Install cron script
+sys-apps/firejail:apparmor - Enable support for custom AppArmor profiles
+sys-apps/firejail:bind - Enable custom bind mounts
+sys-apps/firejail:chroot - Enable chrooting to custom directory
+sys-apps/firejail:contrib - Install contrib scripts
+sys-apps/firejail:file-transfer - Enable file transfers between sandboxes and the host system
+sys-apps/firejail:network - Enable networking features
+sys-apps/firejail:network-restricted - Grant access to --interface, --net=ethXXX and --netfilter only to root user; regular users are only allowed --net=none
+sys-apps/firejail:seccomp - Enable system call filtering
+sys-apps/firejail:userns - Enable attaching a new user namespace to a sandbox (--noroot option)
+sys-apps/firejail:x11 - Enable X11 sandboxing
+sys-apps/firejail-lts:seccomp - Enable system call filtering
+sys-apps/flashrom:atahpt - Highpoint (HPT) ATA/RAID controller support
+sys-apps/flashrom:atapromise - Support for Promise PDC2026x (FastTrak/Ultra)
+sys-apps/flashrom:atavia - Support for VIA VT6421A SATA controllers
+sys-apps/flashrom:bitbang_spi - Bitbanging SPI infrastructure
+sys-apps/flashrom:buspirate_spi - Enable Bus Pirate SPI programmer
+sys-apps/flashrom:ch341a_spi - Enable WCH CH341A SPI programmer
+sys-apps/flashrom:dediprog - Dediprog SF100 support
+sys-apps/flashrom:drkaiser - Enable Dr. Kaiser programmer
+sys-apps/flashrom:dummy - Enable dummy tracing
+sys-apps/flashrom:ft2232_spi - Enable ftdi programmer, flashing through FTDI/SPI USB interface
+sys-apps/flashrom:gfxnvidia - Enable NVIDIA programmer
+sys-apps/flashrom:internal - Enable internal/onboard support
+sys-apps/flashrom:internal_dmi - Enable internal DMI decoding rather than use sys-apps/dmidecode
+sys-apps/flashrom:it8212 - Support for ITE IT8212F ATA/RAID controllers
+sys-apps/flashrom:linux_spi - Enable support for Linux userspace spidev interface
+sys-apps/flashrom:mstarddc_spi - Support for SPI flash ROMs accessible through DDC in MSTAR-equipped displays
+sys-apps/flashrom:nic3com - Enable 3Com NIC programmer
+sys-apps/flashrom:nicintel - Support for Intel NICs
+sys-apps/flashrom:nicintel_eeprom - Support for EEPROMs on Intel Gigabit network cards
+sys-apps/flashrom:nicintel_spi - Support for SPI on Intel NICs
+sys-apps/flashrom:nicnatsemi - Support for National Semiconductor NICs
+sys-apps/flashrom:nicrealtek - Support for Realtek NICs
+sys-apps/flashrom:ogp_spi - Enable support for OGP (Open Graphics Project) SPI flashing
+sys-apps/flashrom:pickit2_spi - SUpport for SPI flash ROMs accessible via Microchip PICkit2
+sys-apps/flashrom:pony_spi - Enable support for SI-Prog like hardware by Lancos
+sys-apps/flashrom:rayer_spi - RayeR SPIPGM hardware support
+sys-apps/flashrom:satamv - Enable programmer for Marvell SATA controllers
+sys-apps/flashrom:satasii - Enable programmer for SiI SATA controllers
+sys-apps/flashrom:serprog - Enable Serial Flasher programmer
+sys-apps/flashrom:tools - Install additional tools
+sys-apps/flashrom:usbblaster - Enable support for Altera USB-Blaster dongles
+sys-apps/flashrom:usbblaster_spi - Enable support for Altera USB-Blaster dongles
+sys-apps/flashrom:wiki - Enable wiki informations, like supported devices etc.
+sys-apps/fwupd:colorhug - Enable ColorHug support through x11-misc/colord package.
+sys-apps/fwupd:dell - Enable Dell-specific support.
+sys-apps/fwupd:gpg - Enable GPG support.
+sys-apps/fwupd:man - Build and install man pages
+sys-apps/fwupd:uefi - Enable UEFI support
+sys-apps/fwupd:uefi_labels - Enable UEFI labels support
+sys-apps/gawk:forced-sandbox - Always enable --sandbox mode for simpler/secure runtime (disables e/r/w commands)
+sys-apps/gawk:mpfr - use mpfr for high precision arithmetic (-M / --bignum)
+sys-apps/gnome-disk-utility:fat - Include FAT16/FAT32 support (sys-fs/dosfstools)
+sys-apps/hwdata-gentoo:binary-drivers - Adds support for ATI/NVIDIA binary drivers
+sys-apps/hwids:net - Install the oui.txt and iab.txt databases
+sys-apps/hwids:pci - Install the pci.ids database
+sys-apps/hwids:udev - Install hwdb.d rules for udev
+sys-apps/hwids:usb - Install the usb.ids database
+sys-apps/hwloc:cuda - Enable CUDA device discovery
+sys-apps/hwloc:gl - Enable GL display device discovery (NVCtrl)
+sys-apps/hwloc:numa - Add support for numa memory allocation
+sys-apps/hwloc:pci - Enable PCI device discovery using libpci
+sys-apps/hwloc:plugins - Build hwloc components as plugins so that the hwloc core library does not directly depend on their dependencies (for instance the libpci library)
+sys-apps/ibm-powerpc-utils:rtas - Add support for the Run Time Abstraction Services (RTAS)
+sys-apps/iotools:make-symlinks - Generate sub-command symlinks to iotools -- note that a lot are simple like "xor"
+sys-apps/ipmitool:openipmi - Use the system OpenIPMI implementation.
+sys-apps/iproute2:berkdb - build programs that use berkdb (just arpd)
+sys-apps/iproute2:elf - support loading eBPF programs from ELFs (e.g. LLVM's eBPF backend)
+sys-apps/iproute2:iptables - include support for iptables filtering
+sys-apps/iproute2:minimal - only install ip and tc programs, without eBPF support
+sys-apps/irqbalance:numa - Support balancing IRQs across NUMA nodes
+sys-apps/kexec-tools:booke - Include support for Book-E memory management
+sys-apps/kexec-tools:lzma - Enables support for LZMA compressed kernel images
+sys-apps/kexec-tools:xen - Enable extended xen support
+sys-apps/kmod:lzma - Enable support for XZ compressed modules
+sys-apps/kmod:tools - Install module loading/unloading tools.
+sys-apps/kmod:zlib - Enable support for gzipped modules
+sys-apps/linux-misc-apps:usbip - Include USB/IP binaries to replace net-misc/usbip
+sys-apps/lm_sensors:contrib - Installs user contributed configuration files so you don't need to find settings on your own for your system if somebody else has already created such a configuration for sensors/mainboards you are using.
+sys-apps/lm_sensors:sensord - Enable sensord - a daemon that can be used to periodically log sensor readings from hardware health-monitoring chips
+sys-apps/man-db:manpager - Enable manpager wrapper for colorizing output
+sys-apps/mawk:forced-sandbox - Always enable -W sandbox mode for simpler/secure runtime
+sys-apps/memtest86:serial - Compile with serial console support
+sys-apps/memtest86+:floppy - Install a script to create floppy disks containing memtest86+ binaries.
+sys-apps/memtest86+:iso - Compile an ISO image
+sys-apps/memtest86+:serial - Compile with serial console support
+sys-apps/moreutils:perl - Install scripts written in Perl
+sys-apps/net-tools:arp - build the arp and rarp tools (for manipulating the ARP cache)
+sys-apps/net-tools:hostname - build the hostname and dnsdomainname tools
+sys-apps/net-tools:plipconfig - build the plipconfig tool (for working with old PLIP hardware)
+sys-apps/net-tools:slattach - build the slattach tool (for working with old serial ports)
+sys-apps/nix:etc_profile - Install /etc/profile.d/ entry to inject nix support for all users.
+sys-apps/nix:gc - Enable garbage collection in the Nix expression evaluator (use dev-libs/boehm-gc).
+sys-apps/nix:sodium - Use dev-libs/libsodium for cryptography
+sys-apps/openrc:netifrc - enable Gentoo's network stack (net.* scripts)
+sys-apps/openrc:newnet - enable the new network stack (experimental)
+sys-apps/pacman:doc - Install extended documentation using app-doc/doxygen. (Man pages are included by default.)
+sys-apps/pacman:gpg - Enable GPG signature verification using app-crypt/gpgme
+sys-apps/paludis:pbins - Enable binary package support. Adds dependency upon app-arch/libarchive
+sys-apps/paludis:pink - Use a less boring colourscheme than the default
+sys-apps/paludis:search-index - Enable cave search --index. Requires dev-db/sqlite.
+sys-apps/paludis:xml - Build xml things for metadata.xml and GLSA support (needs dev-libs/libxml2).
+sys-apps/pciutils:dns - Enable support for querying the central database of PCI IDs using DNS
+sys-apps/pciutils:kmod - Enable sys-apps/kmod support for the -k switch in lspci command
+sys-apps/pciutils:zlib - Support compressed pci.ids database
+sys-apps/pcmciautils:staticsocket - Add support for static sockets
+sys-apps/pcsc-lite:libusb - Use dev-libs/libusb detection to hotplug new smartcard readers. This flag should only be enabled if you're running a non-Linux kernel or you don't want to use sys-fs/udev.
+sys-apps/pcsc-lite:policykit - Uses sys-auth/polkit to restrict access to smartcard readers or smartcars to given users.
+sys-apps/pcsc-lite:udev - Use sys-fs/udev rules to handle devices' permissions and hotplug support. Unless you know what you're doing do not disable this flag on Linux kernels. This is provided as an option for completeness.
+sys-apps/pcsc-tools:network-cron - Monthly cronjob the update-smartcard_list script
+sys-apps/pkgcore:doc - Build and install API docs.
+sys-apps/policycoreutils:audit - Enable support for sys-process/audit and use the audit_* functions (like audit_getuid instead of getuid())
+sys-apps/portage:epydoc - Build html API documentation with epydoc.
+sys-apps/portage:gentoo-dev - Enable features required for Gentoo ebuild development.
+sys-apps/portage:ipc - Use inter-process communication between portage and running ebuilds.
+sys-apps/portage:native-extensions - Compiles native "C" extensions (speedups, instead of using python backup code). Currently includes libc-locales. This should only be temporarily disabled for some bootstrapping operations. Cross-compilation is not supported.
+sys-apps/portage:rsync-verify - Enable full-tree cryptographic verification of Gentoo repository rsync checkouts using app-portage/gemato.
+sys-apps/portage:xattr - Preserve extended attributes (filesystem-stored metadata) when installing files. Usually only required for hardened systems.
+sys-apps/proot:care - Build dynamic CARE binary (more info - http://reproducible.io/)
+sys-apps/qingy:consolekit - Enable native consolekit support
+sys-apps/qingy:opensslcrypt - Encrypt communications between qingy and its GUI using dev-libs/openssl
+sys-apps/razercfg:pm-utils - Installs the pm-utils hooks for suspend/resume and requires sys-power/pm-utils
+sys-apps/razercfg:qt4 - Installs a qt UI. Requires dev-python/pyside
+sys-apps/rng-tools:nistbeacon - Enable NIST beacon entropy support
+sys-apps/roccat-tools:input_devices_roccat_ryosmkfx - Enable support for Ryos Mk FX keyboard.
+sys-apps/roccat-tools:input_devices_roccat_skeltr - Enable support for Skeltr keyboard.
+sys-apps/roccat-tools:input_devices_roccat_sova - Enable support for Sova keyboard.
+sys-apps/roccat-tools:input_devices_roccat_suora - Enable support for Suora keyboard.
+sys-apps/s390-tools:fuse - build cmsfs-fuse to read files stored on a z/VM CMS disk
+sys-apps/s390-tools:ncurses - build hyptop monitoring program
+sys-apps/s390-tools:pfm - build the cpacfstats tool
+sys-apps/s390-tools:zfcpdump - build the kernel disk dumping utility
+sys-apps/s390-tools:zlib - build the zgetdump utility
+sys-apps/sed:forced-sandbox - Always enable --sandbox mode for simpler/secure runtime (disables e/r/w commands)
+sys-apps/selinux-python:audit - Enable support for sys-process/audit and use the audit_* functions (like audit_getuid instead of getuid())
+sys-apps/smartmontools:caps - Build against sys-libs/libcap-ng to allow smartd to drop its privileges.
+sys-apps/smartmontools:daemon - Install the monitoring daemon (smartd) and associated scripts.
+sys-apps/smartmontools:minimal - Do not install the monitoring daemon and associated scripts.
+sys-apps/smartmontools:update_drivedb - Install a script to update the drivedb file.
+sys-apps/superiotool:pci - Support for PCI-attached "Super I/Os" (e.g. in VIA VT82686A/B).
+sys-apps/systemd:apparmor - Enable AppArmor support
+sys-apps/systemd:audit - Enable support for sys-process/audit
+sys-apps/systemd:cryptsetup - Enable cryptsetup tools (includes unit generator for crypttab)
+sys-apps/systemd:curl - Enable support for uploading journals
+sys-apps/systemd:doc - Generate systemd.index.7 and systemd.directives.7
+sys-apps/systemd:elfutils - Enable coredump stacktraces in the journal
+sys-apps/systemd:gcrypt - Enable sealing of journal files using gcrypt
+sys-apps/systemd:gnuefi - Enable EFI boot manager and stub loader (built using sys-boot/gnu-efi)
+sys-apps/systemd:http - Enable embedded HTTP server in journald
+sys-apps/systemd:importd - Enable import daemon
+sys-apps/systemd:kmod - Enable kernel module loading via sys-apps/kmod
+sys-apps/systemd:libidn2 - If IDN support is enabled, use net-dns/libidn2 instead of net-dns/libidn
+sys-apps/systemd:lz4 - Enable lz4 compression for the journal
+sys-apps/systemd:nat - Enable support for network address translation in networkd
+sys-apps/systemd:qrcode - Enable qrcode output support in journal
+sys-apps/systemd:sysv-utils - Install sysvinit compatibility symlinks and manpages for init, telinit, halt, poweroff, reboot, runlevel, and shutdown
+sys-apps/systemd:usrmerge - Enable /usr merge (experimental)
+sys-apps/systemd:vanilla - Disable Gentoo-specific behavior and compatibility quirks
+sys-apps/systemd:xkb - Depend on x11-libs/libxkbcommon to allow logind to control the X11 keymap
+sys-apps/tcp-wrappers:netgroups - Support matching NIS (host) netgroup names via the @netgroup syntax (if you don't know what this means, you most likely do not need it)
+sys-apps/timer_entropyd:debug - Enable printf debugging and logging to the syslog at DEBUG level
+sys-apps/usb_modeswitch:jimtcl - Use dev-lang/jimtcl instead of dev-lang/tcl for smaller memory footprint
+sys-apps/usermode-utilities:fuse - Build tools (currently umlmount) needing fuse
+sys-apps/util-linux:caps - build setpriv helper (run programs with diff capabilities)
+sys-apps/util-linux:cramfs - build mkfs/fsck helpers for cramfs filesystems
+sys-apps/util-linux:fdformat - build fdformat (floppy disk format)
+sys-apps/util-linux:kill - build the kill program
+sys-apps/util-linux:pam - build runuser helper
+sys-apps/util-linux:suid - install mount/umount as setuid so non-root users may mount/umount devices, and wall/write as setgid so non-root users can notify other users
+sys-apps/util-linux:tty-helpers - install the mesg/wall/write tools for talking to local users
+sys-apps/watchdog:nfs - enable support for checking nfs mounts
+sys-apps/xinetd:rpc - support RPC services
+sys-auth/consolekit:cgroups - Use the kernel to track processes instead of the session cookie.
+sys-auth/consolekit:evdev - For handling VT switching with a session controller.
+sys-auth/consolekit:pm-utils - Adds support for suspend/resume using sys-power/pm-utils
+sys-auth/consolekit:policykit - Use the PolicyKit framework (sys-auth/polkit) to get authorization for suspend/shutdown.
+sys-auth/consolekit:systemd-units - Install systemd unit files to replace the modern functionality of logind in sys-apps/systemd. Not recommended.
+sys-auth/fingerprint-gui:upekbsapi - Add UPEK BSAPI drivers for identify functions on some readers
+sys-auth/keystone:memcached - Installs dependencies needed for using memcached as a backend
+sys-auth/keystone:mongo - Installs dependencies needed for using mongo as a backend
+sys-auth/munge:gcrypt - Use libgcrypt instead of openssl
+sys-auth/nss-mdns:search-domains - Honour search domains from /etc/resolv.conf (see bug #201948 for possible side effects)
+sys-auth/nss-pam-ldapd:pynslcd - Install the python implementation along with the standard implementation
+sys-auth/nss-pam-ldapd:utils - Install the command-line utilities
+sys-auth/oath-toolkit:pam - Build PAM module for pluggable login authentication for OATH
+sys-auth/oath-toolkit:pskc - Build tools & library for the Portable Symmetric Key Container (PSKC) format per RFC6030
+sys-auth/pam_mktemp:prevent-removal - If supported, set EXT2_APPEND_FL on /tmp/.private to prevent temporary directories from being removed
+sys-auth/pam_mysql:openssl - Use OpenSSL for md5 and sha1 support
+sys-auth/pam_u2f:debug - Enable debug messages using the pam logging macros. (Note: these will be visible on stdout for terminal logins).
+sys-auth/pambase:consolekit - Enable pam_ck_connector module on local system logins. This allows for console logins to make use of ConsoleKit authorization.
+sys-auth/pambase:cracklib - Enable pam_cracklib module on system authentication stack. This produces warnings when changing password to something easily crackable. It requires the same USE flag to be enabled on sys-libs/pam or system login might be impossible.
+sys-auth/pambase:debug - Enable debug information logging on syslog(3) for all the modules supporting this in the system authentication and system login stacks.
+sys-auth/pambase:elogind - Use pam_elogind module to register user sessions with elogind.
+sys-auth/pambase:gnome-keyring - Enable pam_gnome_keyring module on system login stack. This enables proper Gnome Keyring access to logins, whether they are done with the login shell, a Desktop Manager or a remote login systems such as SSH.
+sys-auth/pambase:minimal - Disables the standard PAM modules that provide extra information to users on login; this includes pam_tally (and pam_tally2 for Linux PAM 1.1 and later), pam_lastlog, pam_motd and other similar modules. This might not be a good idea on a multi-user system but could reduce slightly the overhead on single-user non-networked systems.
+sys-auth/pambase:mktemp - Enable pam_mktemp module on system auth stack for session handling. This module creates a private temporary directory for the user, and sets TMP and TMPDIR accordingly.
+sys-auth/pambase:nullok - Enable the nullok option with the pam_unix module. This allows people to login with blank passwords.
+sys-auth/pambase:pam_krb5 - Enable pam_krb5 module on system auth stack, as an alternative to pam_unix. If Kerberos authentication succeed, only pam_unix will be ignore, and all the other modules will proceed as usual, including Gnome Keyring and other session modules. It requires sys-libs/pam as PAM implementation.
+sys-auth/pambase:pam_ssh - Enable pam_ssh module on system auth stack for authentication and session handling. This module will accept as password the passphrase of a private SSH key (one of ~/.ssh/id_rsa, ~/.ssh/id_dsa or ~/.ssh/identity), and will spawn an ssh-agent instance to cache the open key.
+sys-auth/pambase:passwdqc - Enable pam_passwdqc module on system auth stack for password quality validation. This is an alternative to pam_cracklib producing warnings, rejecting or providing example passwords when changing your system password. It is used by default by OpenWall GNU/*/Linux and by FreeBSD.
+sys-auth/pambase:securetty - Enable pam_securetty module in the login stack. Not generally relevant anymore as the login stack only refers to local logins and local terminals imply secure access in the first place.
+sys-auth/pambase:sha512 - Switch Linux-PAM's pam_unix module to use sha512 for passwords hashes rather than MD5. This option requires sys-libs/pam version 1.0.1 built against sys-libs/glibc version 2.7, if it's built against an earlier version, it will silently be ignored, and MD5 hashes will be used. All the passwords changed after this USE flag is enabled will be saved to the shadow file hashed using SHA512 function. The password previously saved will be left untouched. Please note that while SHA512-hashed passwords will still be recognised if the USE flag is removed, the shadow file will not be compatible with systems using an earlier glibc version.
+sys-auth/pambase:systemd - Use pam_systemd module to register user sessions in the systemd control group hierarchy.
+sys-auth/passwdqc:utils - Install pwqcheck and pwqgen helper utilities
+sys-auth/polkit:elogind - Use sys-auth/elogind instead of sys-auth/consolekit for session tracking
+sys-auth/polkit:systemd - Use sys-apps/systemd instead of sys-auth/consolekit for session tracking
+sys-auth/sssd:acl - Build and use the cifsidmap plugin
+sys-auth/sssd:augeas - Build internal configuration library
+sys-auth/sssd:autofs - Build helper to let net-fs/autofs use sssd provided information
+sys-auth/sssd:locator - Install sssd's Kerberos plugin
+sys-auth/sssd:manpages - Build man pages with dev-libs/libxslt
+sys-auth/sssd:netlink - Add support for netlink protocol via dev-libs/libnl
+sys-auth/sssd:nfsv4 - Add support for the nfsv4 idmapd plugin provided by net-libs/libnfsidmap
+sys-auth/sssd:ssh - Build helper to let net-misc/openssh use sssd provided information
+sys-auth/sssd:sudo - Build helper to let app-admin/sudo use sssd provided information
+sys-auth/ykpers:consolekit - Use sys-auth/consolekit and virtual/udev to allow access to the YubiKey HID device to the console user.
+sys-block/f3:extra - Build the additional f3probe, f3brew and f3fix utility (requires sys-block/parted and virtual/udev)
+sys-block/fio:aio - Enable AIO ioengine
+sys-block/fio:glusterfs - Enable GlusterFS gfapi support via sys-cluster/glusterfs
+sys-block/fio:gnuplot - Install tools for generating gnuplots
+sys-block/fio:numa - Enable numa support
+sys-block/fio:rbd - Enable Rados block device support via sys-cluster/ceph
+sys-block/fio:rdma - Enable infiniband support via sys-fabric/librdmacm
+sys-block/gparted:btrfs - Include Btrfs support (sys-fs/btrfs-progs)
+sys-block/gparted:cryptsetup - Include LUKS volume support (sys-fs/cryptsetup)
+sys-block/gparted:dmraid - Support for dmraid devices, also known as ATA-RAID, or Fake RAID.
+sys-block/gparted:f2fs - Include F2FS support (sys-fs/f2fs-tools)
+sys-block/gparted:fat - Include FAT16/FAT32 support (sys-fs/dosfstools)
+sys-block/gparted:hfs - Include HFS support (sys-fs/hfsutils)
+sys-block/gparted:jfs - Include JFS support (sys-fs/jfsutils)
+sys-block/gparted:mdadm - Support for Linux software RAID.
+sys-block/gparted:ntfs - Include NTFS support (sys-fs/ntfs3g)
+sys-block/gparted:reiser4 - Include ReiserFS4 support (sys-fs/reiser4progs)
+sys-block/gparted:reiserfs - Include ReiserFS support (sys-fs/reiserfsprogs)
+sys-block/gparted:udf - Include UDF support (sys-fs/udftools)
+sys-block/gparted:xfs - Include XFS support (sys-fs/xfsprogs, sys-fs/xfsdump)
+sys-block/open-iscsi:rdma - Support iSCSI over RDMA
+sys-block/open-iscsi:tcp - Support iSCSI over TCP
+sys-block/parted:debug - Enable debugging as encouraged by upstream: [The default configuration] includes --enable-debug (by default), which contains many assertions. Obviously, these "waste" space, but in the past, they have caught potentially dangerous bugs before they would have done damage, so we think it's worth it. Also, it means we get more bug reports ;)
+sys-block/parted:device-mapper - Enable device-mapper support from sys-fs/lvm2 in parted
+sys-block/partimage:nologin - Do not include login support when connecting partimaged
+sys-block/perccli:efi - Install EFI variant as well
+sys-block/sas2ircu:efi - Install EFI variant as well
+sys-block/sas3flash:efi - Install EFI variant as well
+sys-block/sas3ircu:efi - Install EFI variant as well
+sys-block/tgt:fcoe - Add support for FCoE protocol
+sys-block/tgt:fcp - Add support for new FC protocol
+sys-block/tgt:ibmvio - Add support for IBM Virtual I/O
+sys-block/tgt:rbd - Add support for ceph block devices
+sys-boot/grub:device-mapper - Enable support for device-mapper from sys-fs/lvm2
+sys-boot/grub:efiemu - Build and install the efiemu runtimes
+sys-boot/grub:fonts - Build and install fonts for the gfxterm module
+sys-boot/grub:libzfs - Enable support for sys-fs/zfs
+sys-boot/grub:mount - Build and install the grub-mount utility
+sys-boot/grub:multislot - Allow concurrent installation of sys-boot/grub SLOT 0 and sys-boot/grub SLOT 2 by renaming all programs.
+sys-boot/grub:themes - Build and install GRUB themes (starfield)
+sys-boot/grub:truetype - Build and install grub-mkfont conversion utility
+sys-boot/lilo:device-mapper - Enable support for device-mapper from sys-fs/lvm2
+sys-boot/lilo:minimal - Do not install the dolilo helper script
+sys-boot/lilo:pxeserial - Avoid character echo on PXE serial console
+sys-boot/plymouth:gdm - Enables smooth transition to GDM
+sys-boot/plymouth:libkms - Provides abstraction to the DRM drivers (intel, nouveau and vmwgfx at this moment)
+sys-boot/plymouth:pango - Adds support for printing text on splash screen and text prompts, e.g. for password
+sys-boot/refind:btrfs - Builds the EFI binary btrfs filesystem driver
+sys-boot/refind:ext2 - Builds the EFI binary ext2 filesystem driver
+sys-boot/refind:ext4 - Builds the EFI binary ext4 filesystem driver
+sys-boot/refind:gnuefi - Compile using GNU-EFI instead of Tianocore
+sys-boot/refind:hfs - Builds the EFI binary hfs filesystem driver
+sys-boot/refind:iso9660 - Builds the EFI binary iso9660 filesystem driver
+sys-boot/refind:ntfs - Builds the EFI binary ntfs filesystem driver
+sys-boot/refind:reiserfs - Builds the EFI binary reiserfs filesystem driver
+sys-cluster/ceph:babeltrace - Add support for LTTng babeltrace
+sys-cluster/ceph:cephfs - Build support for cephfs, a POSIX compatible filesystem built on top of ceph
+sys-cluster/ceph:cryptopp - Use dev-libs/crypto++ for cryptography
+sys-cluster/ceph:fuse - Build fuse client
+sys-cluster/ceph:jemalloc - Use dev-libs/jemalloc for allocations
+sys-cluster/ceph:libaio - Use libaio as asynchronous input/output library
+sys-cluster/ceph:libatomic - Use libatomic instead of builtin atomic operations
+sys-cluster/ceph:lttng - Add support for LTTng
+sys-cluster/ceph:mgr - Build the ceph-mgr daemon
+sys-cluster/ceph:nss - Use dev-libs/nss for cryptography
+sys-cluster/ceph:radosgw - Add radosgw support
+sys-cluster/ceph:system-boost - Use system dev-libs/boost instead of the bundled one
+sys-cluster/ceph:xfs - Add xfs support
+sys-cluster/ceph:zfs - Add zfs support
+sys-cluster/charm:ampi - Build implementation of MPI on top of Charm++
+sys-cluster/charm:charmdebug - Enable the charm debugger
+sys-cluster/charm:charmproduction - Optimize performance of Charm++ runtime
+sys-cluster/charm:charmtracing - Enable tracing support in Charm++
+sys-cluster/charm:cmkopt - Enable CMK optimisation
+sys-cluster/charm:mlogft - Compile with Charm++ message logging fault tolerance support
+sys-cluster/charm:numa - Support memory affinity with NUMA
+sys-cluster/charm:syncft - Compile with Charm++ fault tolerance support
+sys-cluster/charm:tcp - Use TCP (instead of UPD) for socket communication
+sys-cluster/cinder:api - Installs the initscripts for the cinder api service
+sys-cluster/cinder:iscsi - Allow using an iSCSI remote storage server as pool for disk image storage
+sys-cluster/cinder:lvm - Allow using the Logical Volume Manager (sys-fs/lvm2) as pool for disk image storage
+sys-cluster/cinder:memcached - Installs the memcached server
+sys-cluster/cinder:rdma - Enable rdma storage backend support
+sys-cluster/cinder:scheduler - Installs the initscripts for the cinder scheduler service
+sys-cluster/cinder:tcp - Enables tcp support for the iscsi backend
+sys-cluster/cinder:tgt - Enable tgt storage backend support
+sys-cluster/cinder:volume - Installs the initscripts for the cinder volume service
+sys-cluster/cluster-glue:libnet - Force use of net-libs/libnet
+sys-cluster/corosync:infiniband - Enable Infiniband RDMA transport support
+sys-cluster/drbd:heartbeat - Enable Heartbeat integration
+sys-cluster/drbd:pacemaker - Enable Pacemaker integration
+sys-cluster/drbd:xen - Enable Xen integration
+sys-cluster/drbd-utils:heartbeat - Enable Heartbeat integration
+sys-cluster/drbd-utils:pacemaker - Enable Pacemaker integration
+sys-cluster/drbd-utils:xen - Enable Xen integration
+sys-cluster/galera:garbd - Install Galera Arbitrator - a stateless daemon which acts as a lightweight group member
+sys-cluster/gearmand:memcache - Support memcache daemon (via dev-libs/libmemcached) for the queue storage.
+sys-cluster/gearmand:tokyocabinet - Support dev-db/tokyocabinet for the queue storage.
+sys-cluster/glusterfs:bd-xlator - Enable the blockdevice translator (requires sys-fs/lvm2)
+sys-cluster/glusterfs:crypt-xlator - Enable the encryption translator
+sys-cluster/glusterfs:fuse - Add FUSE mount helper
+sys-cluster/glusterfs:georeplication - Enable support for georeplication (requires dev-lang/python)
+sys-cluster/glusterfs:glupy - Enable support for translators written in Python
+sys-cluster/glusterfs:infiniband - Add support for Infiniband ibverbs transport. Libraries can be found in science overlay
+sys-cluster/glusterfs:ipv6 - Use IPv6 by default, requires libtirpc
+sys-cluster/glusterfs:libtirpc - Build against net-libs/libtirpc for RPC support
+sys-cluster/glusterfs:qemu-block - Transparently create files as QCow2/QED images in the backend, including the possibility to snapshot.
+sys-cluster/glusterfs:rsyslog - Install configuration snippet for app-admin/rsyslog
+sys-cluster/glusterfs:systemtap - Enable support for dev-util/systemtap
+sys-cluster/glusterfs:tiering - Enable support for data classification/tiering (requires dev-db/sqlite SLOT 3)
+sys-cluster/heat:memcached - Installs the memcached server
+sys-cluster/hpx:jemalloc - Use dev-libs/jemalloc for memory allocation
+sys-cluster/hpx:papi - Use dev-libs/papi for NaCl
+sys-cluster/hpx:perftools - Use dev-util/google-perftools for memory allocation
+sys-cluster/hpx:tbb - Use dev-cpp/tbb for memory allocation
+sys-cluster/keepalived:json - compile with signal to dump configuration and stats as JSON.
+sys-cluster/legion:gasnet - Enable GASNet lib support
+sys-cluster/legion:hwloc - Enable HWLoc lib support
+sys-cluster/maui:pbs - Enable pbs integration
+sys-cluster/maui:slurm - Enable slurm integration
+sys-cluster/moosefs:cgi - Install CGI server and scripts.
+sys-cluster/moosefs:fuse - Install the mfsmount utility.
+sys-cluster/mpich:mpi-threads - Enable MPI_THREAD_MULTIPLE
+sys-cluster/mpich:romio - Build the ROMIO MPI-IO component
+sys-cluster/mpich2:mpi-threads - Enable MPI_THREAD_MULTIPLE
+sys-cluster/mpich2:romio - Enable romio, a high-performance portable MPI-IO implementation
+sys-cluster/mvapich2:large-cluster - Automatically generated description for large-cluster
+sys-cluster/mvapich2:medium-cluster - Automatically generated description for medium-cluster
+sys-cluster/mvapich2:romio - Automatically generated description for romio
+sys-cluster/neutron:compute-only - Only install things needed on compute hosts
+sys-cluster/neutron:dhcp - Installs the initscripts for the neutron dhcp service
+sys-cluster/neutron:haproxy - haproxy backend support
+sys-cluster/neutron:l3 - Installs the initscripts for the neutron l3 agent service
+sys-cluster/neutron:linuxbridge - Installs the initscripts for the neutron linuxbridge agent service
+sys-cluster/neutron:metadata - Installs the initscripts for the neutron metadata agent service
+sys-cluster/neutron:openvswitch - Installs the initscripts for the neutron openvswitch agent service
+sys-cluster/neutron:server - Installs the initscripts for the neutron server service
+sys-cluster/nova:compute - Installs the initscripts for the nova volume service
+sys-cluster/nova:compute-only - only install stuff needed for a compute host
+sys-cluster/nova:iscsi - Installs iscsi helper udev scripts
+sys-cluster/nova:memcached - Installs the memcached server
+sys-cluster/nova:novncproxy - Installs the initscripts for the nova novncproxy service
+sys-cluster/nova:openvswitch - Installs openvswitch for the neutron openvswitch support
+sys-cluster/nova:rabbitmq - Installs the rabbitmq server
+sys-cluster/ocfs:aio - Add aio support
+sys-cluster/openmpi:cma - Enable the CMA (Cross Memory Attach) MCA
+sys-cluster/openmpi:cuda - Add GPU direct support
+sys-cluster/openmpi:heterogeneous - Enable features required for heterogeneous platform support
+sys-cluster/openmpi:mpi-threads - Enable MPI_THREAD_MULTIPLE
+sys-cluster/openmpi:numa - Enable numactl to allow binding processes to CPUs
+sys-cluster/openmpi:pbs - Add support for the Portable Batch System (PBS)
+sys-cluster/openmpi:romio - Build the ROMIO MPI-IO component
+sys-cluster/openmpi:vt - Enable bundled VampirTrace support
+sys-cluster/openstack-meta:cinder - Installs Openstack Cinder
+sys-cluster/openstack-meta:glance - Installs Openstack Glance
+sys-cluster/openstack-meta:heat - Installs Openstack Heat
+sys-cluster/openstack-meta:keystone - Installs Openstack Keystone
+sys-cluster/openstack-meta:neutron - Installs Openstack Neutron
+sys-cluster/openstack-meta:nova - Installs Openstack Nova
+sys-cluster/openstack-meta:swift - Installs Openstack Swift
+sys-cluster/pacemaker:cman - Enable sys-cluster/cman support.
+sys-cluster/pacemaker:heartbeat - Enable sys-cluster/heartbeat support.
+sys-cluster/pacemaker:smtp - Enable SMTP support via net-libs/libesmtp
+sys-cluster/resource-agents:libnet - Force use of net-libs/libnet
+sys-cluster/resource-agents:rgmanager - Install resources for sys-cluster/rgmanager
+sys-cluster/singularity:slurm - Compile spank plugin for sys-cluster/slurm
+sys-cluster/slurm:multiple-slurmd - Allow multiple slurmd to run
+sys-cluster/slurm:munge - Enable authentication via munge
+sys-cluster/slurm:torque - Enable perl scripts that emulates pbs (qstat, qsub etc.)
+sys-cluster/swift:account - adds swift account support
+sys-cluster/swift:container - adds swift container support
+sys-cluster/swift:memcached - adds memcached support
+sys-cluster/swift:object - adds swift object support
+sys-cluster/swift:proxy - adds swift proxy support
+sys-cluster/torque:autorun - Enable the AUTORUN_JOBS codebase
+sys-cluster/torque:cgroups - Enable pbs_mom to use linux cgroups to isolate jobs
+sys-cluster/torque:cpusets - Enable pbs_mom to utilize linux cpusets if available
+sys-cluster/torque:drmaa - Enable the Distributed Resource Management Application API
+sys-cluster/torque:munge - Enable authentication via munge
+sys-cluster/torque:nvidia - Enable management of Nvidia GPUs
+sys-cluster/torque:quickcommit - Enable the QUICKCOMMIT codebase
+sys-cluster/torque:server - Enable compilation of pbs_server and pbs_sched
+sys-cluster/vzctl:ploop - Add support for ploop devices via sys-cluster/ploop
+sys-cluster/vzctl:vzmigrate - Add support for container migration
+sys-devel/autogen:libopts - install the libopts tarball (a few packages want this for developing)
+sys-devel/binutils:multitarget - Adds support to binutils for cross compiling (does not work with gas)
+sys-devel/binutils-apple:classic - Use nm, otool, etc. from this ebuild instead of llvm-based tools
+sys-devel/binutils-apple:libcxx - Add support for libcxx
+sys-devel/binutils-apple:lto - Add support for Link-Time Optimization with LLVM
+sys-devel/binutils-apple:multitarget - Compile for non-standard target architectures (ppc and ppc64) -- experimental, Gentoo only
+sys-devel/binutils-apple:tapi - Build against sys-libs/tapi
+sys-devel/binutils-hppa64:multitarget - Adds support to binutils for cross compiling (does not work with gas)
+sys-devel/clang:default-compiler-rt - Use compiler-rt instead of libgcc as the default rtlib for clang
+sys-devel/clang:default-libcxx - Use libc++ instead of libstdc++ as the default stdlib for clang
+sys-devel/clang:multitarget - Build all host targets (default: host only)
+sys-devel/clang:static-analyzer - Install the Clang static analyzer
+sys-devel/clang:z3 - Enable the static analyzer constraint manager backend using sci-mathematics/z3
+sys-devel/clang-runtime:compiler-rt - Install sys-libs/compiler-rt for -rtlib=compiler-rt
+sys-devel/clang-runtime:libcxx - Install sys-libs/libcxx for -stdlib=libc++
+sys-devel/clang-runtime:openmp - Install sys-libs/libomp for -fopenmp support
+sys-devel/clang-runtime:sanitize - Enable compiler-rt sanitizer (-fsanitize*) support
+sys-devel/distcc:crossdev - Enable support for sys-devel/crossdev
+sys-devel/distcc:gssapi - Enable support for net-libs/libgssglue
+sys-devel/gcc:awt - Useful only when building GCJ, this enables Abstract Window Toolkit (AWT) peer support on top of GTK+
+sys-devel/gcc:cilk - Support the Cilk Plus language (C/C++ based languages for parallel programming)
+sys-devel/gcc:d - Enable support for the D programming language
+sys-devel/gcc:fixed-point - Enable fixed-point arithmetic support for MIPS targets in gcc (Warning: significantly increases compile time!)
+sys-devel/gcc:go - Build the GCC Go language frontend.
+sys-devel/gcc:graphite - Add support for the framework for loop optimizations based on a polyhedral intermediate representation
+sys-devel/gcc:jit - Enable libgccjit so other applications can embed gcc for Just-In-Time compilation. This will slow down the compiler a bit as it forces all of the toolchain to be shared libs.
+sys-devel/gcc:libssp - Build SSP support into a dedicated library rather than use the code in the C library (DO NOT ENABLE THIS IF YOU DON'T KNOW WHAT IT DOES)
+sys-devel/gcc:mpx - Enable support for Intel Memory Protection Extensions (MPX)
+sys-devel/gcc:mudflap - Add support for mudflap, a pointer use checking library
+sys-devel/gcc:nopie - Disable PIE support (NOT FOR GENERAL USE)
+sys-devel/gcc:nossp - Disable SSP support (NOT FOR GENERAL USE)
+sys-devel/gcc:objc - Build support for the Objective C code language
+sys-devel/gcc:objc++ - Build support for the Objective C++ language
+sys-devel/gcc:objc-gc - Build support for the Objective C code language Garbage Collector
+sys-devel/gcc:pgo - Build GCC using Profile Guided Optimization (PGO)
+sys-devel/gcc:regression-test - Run the testsuite and install the results (requires FEATURES=test)
+sys-devel/gcc:sanitize - Build support for various sanitizer functions (ASAN/TSAN/etc...)
+sys-devel/gcc:ssp - Build packages with stack smashing protector on by default
+sys-devel/gcc:vtv - Build support for virtual table verification (a C++ hardening feature)
+sys-devel/gcc-apple:objc - Build support for the Objective C code language
+sys-devel/gcc-apple:objc++ - Build support for the Objective C++ language
+sys-devel/gcc-apple:regression-test - Run the testsuite and install the results (requires FEATURES=test)
+sys-devel/gdb:client - Install the main "gdb" program (most people want this)
+sys-devel/gdb:lzma - Support lzma compression in ELF debug info
+sys-devel/gdb:multitarget - Support all known targets in one gdb binary
+sys-devel/gdb:python - Enable support for the new internal scripting language, as well as extended pretty printers
+sys-devel/gdb:server - Install the "gdbserver" program (useful for embedded/remote targets)
+sys-devel/gdb:xml - Support parsing XML data files needed (at least) for cpu features, memory maps, and syscall tracing
+sys-devel/gettext:cvs - When running `autopoint`, use cvs to store the internal development files; this requires cvs at runtime, but will be faster/smaller than raw archives
+sys-devel/gettext:git - When running `autopoint`, use git to store the internal development files; this requires git at runtime, but will be faster/smaller than raw archives
+sys-devel/kgcc64:regression-test - Run the testsuite and install the results (requires FEATURES=test)
+sys-devel/llvm:clang - Build the clang C/C++ compiler
+sys-devel/llvm:default-compiler-rt - Use compiler-rt instead of libgcc as the default rtlib for clang
+sys-devel/llvm:default-libcxx - Use libc++ instead of libstdc++ as the default stdlib for clang
+sys-devel/llvm:doc - Build and install the HTML documentation and regenerate the man pages
+sys-devel/llvm:gold - Build the gold linker plugin
+sys-devel/llvm:lldb - Build the lldb debugger
+sys-devel/llvm:multitarget - Build all host targets (default: host only)
+sys-devel/llvm:ncurses - Support querying terminal properties using ncurses' terminfo
+sys-devel/llvm:sanitize - Build compiler-rt's sanitizers
+sys-devel/llvm:static-analyzer - Install the Clang static analyzer (requires USE=clang)
+sys-devel/llvm:xar - Support dumping LLVM bitcode sections in Mach-O files (uses app-arch/xar)
+sys-devel/sparse:gtk - Build the test-inspect utility (requires x11-libs/gtk+ version 2)
+sys-devel/sparse:llvm - Build the sparse-llvm utility
+sys-devel/sparse:xml - Build the c2xml utility (requires dev-libs/libxml2)
+sys-fabric/ofed:dapl - Add support for DAPL abstraction layer
+sys-fabric/ofed:diags - Add dignostic tools for infiniband
+sys-fabric/ofed:ibacm - Add support for userspace pre-connection services
+sys-fabric/ofed:mstflint - Tools to burn Mellanox firmware
+sys-fabric/ofed:opensm - Add OpenSM - Subnet manager for infiniband
+sys-fabric/ofed:perftest - Add perftest utils
+sys-fabric/ofed:qperf - Add rdma tests
+sys-fabric/ofed:rds - Tools to manage rds sockets
+sys-fabric/ofed:srp - Suport for userspace part for srp initiator
+sys-fabric/opensm:tools - Install ssld extra tool
+sys-firmware/edk2-ovmf:binary - Use pre-built binaries
+sys-firmware/intel-microcode:initramfs - install a small initramfs for use with CONFIG_MICROCODE_EARLY
+sys-firmware/intel-microcode:monolithic - install the large text microcode.dat (used by older kernels via microcode_ctl)
+sys-firmware/intel-microcode:split-ucode - install the split binary ucode files (used by the kernel directly)
+sys-firmware/ipxe:binary - Use pre-built binaries
+sys-firmware/ipxe:efi - Build an EFI program for using PXE
+sys-firmware/ipxe:iso - Build a bootable ISO for using PXE
+sys-firmware/ipxe:lkrn - Build a linux kernel bootable file for using with grub/etc...
+sys-firmware/ipxe:qemu - Build the required PXE ROM images for app-emulation/qemu
+sys-firmware/ipxe:undi - Build a Universal Network Device Interface driver chainloading your existing PXE NIC into iPXE
+sys-firmware/ipxe:usb - Build a bootable USB image for using PXE
+sys-firmware/ipxe:vmware - Build the PXE ROM images that VMWare uses
+sys-firmware/seabios:binary - Use official upstream pre-built binaries
+sys-firmware/seabios:seavgabios - Include SeaVGABIOS binaries (replacement for vgabios)
+sys-firmware/sgabios:binary - Use pre-built binaries
+sys-firmware/sigrok-firmware-fx2lafw:binary - Use official upstream pre-built binaries
+sys-firmware/vgabios:binary - Use official upstream pre-built binaries (only default and cirrus images)
+sys-freebsd/boot0:tftp - Enable PXE/TFTP boot support.
+sys-freebsd/boot0:zfs - Enable booting on ZFS filesystems.
+sys-freebsd/freebsd-lib:hesiod - Enable support for net-dns/hesiod
+sys-freebsd/freebsd-lib:netware - Build libraries and tools to work with NetWare protocols (IPX and NCP).
+sys-freebsd/freebsd-lib:zfs - Enable ZFS support.
+sys-freebsd/freebsd-rescue:netware - Build tools to work with NetWare protocols (IPX and NCP).
+sys-freebsd/freebsd-rescue:zfs - Enable ZFS support.
+sys-freebsd/freebsd-sbin:ipfilter - Build tools to administer the ipfilter firewall.
+sys-freebsd/freebsd-sbin:netware - Build libraries and tools to work with NetWare protocols (IPX and NCP).
+sys-freebsd/freebsd-sbin:pf - Build tools to administer the PF firewall.
+sys-freebsd/freebsd-sbin:zfs - Enable ZFS support.
+sys-freebsd/freebsd-share:zfs - Enable ZFS support.
+sys-freebsd/freebsd-sources:build-kernel - Build and install a kernel (recommended).
+sys-freebsd/freebsd-sources:dtrace - Enable DTrace support.
+sys-freebsd/freebsd-sources:zfs - Enable ZFS support.
+sys-freebsd/freebsd-ubin:ar - Build FreeBSD's ar and ranlib replacements based on libarchive. The toolchain will still use binutils' version but you can play with it. They have been renamed to freebsd-ar and freebsd-ranlib not to collide with binutils.
+sys-freebsd/freebsd-ubin:audit - Build auditing tools
+sys-freebsd/freebsd-ubin:netware - Build libraries and tools to work with NetWare protocols (IPX and NCP)
+sys-freebsd/freebsd-ubin:zfs - Enable ZFS support (for fstat actually).
+sys-freebsd/freebsd-usbin:audit - Build auditing tools.
+sys-freebsd/freebsd-usbin:floppy - Enable floppy disk utilities (fdcontrol, fdformat, fdread, fdwrite).
+sys-freebsd/freebsd-usbin:netware - Build libraries and tools to work with NetWare protocols (IPX and NCP).
+sys-freebsd/freebsd-usbin:zfs - Enable ZFS support.
+sys-fs/aufs3:debug - Enable additional debugging support
+sys-fs/aufs3:fuse - Enable fuse support
+sys-fs/aufs3:hfs - Enable hfs support
+sys-fs/aufs3:inotify - Enable inotify support
+sys-fs/aufs3:kernel-patch - Patch the current kernel for aufs3 support
+sys-fs/aufs3:nfs - Enable support for nfs export
+sys-fs/aufs3:pax_kernel - Apply patch needed for pax enabled kernels
+sys-fs/aufs3:ramfs - Enable initramfs/rootfs support
+sys-fs/aufs4:debug - Enable additional debugging support
+sys-fs/aufs4:fuse - Enable fuse support
+sys-fs/aufs4:hfs - Enable hfs support
+sys-fs/aufs4:inotify - Enable inotify support
+sys-fs/aufs4:kernel-patch - Patch the current kernel for aufs3 support
+sys-fs/aufs4:nfs - Enable support for nfs export
+sys-fs/aufs4:pax_kernel - Apply patch needed for pax enabled kernels
+sys-fs/aufs4:ramfs - Enable initramfs/rootfs support
+sys-fs/btrfs-progs:convert - Build ext2 conversion utility (btrfs-convert)
+sys-fs/btrfs-progs:reiserfs - Enable reiserfs support in btrfs-convert tool.
+sys-fs/btrfs-progs:static - Build static binaries in addition to the dynamic ones
+sys-fs/btrfs-progs:zstd - Enable zstd compression support.
+sys-fs/btrfsmaintenance:systemd - Enable systemd services and timers instead of cron timers
+sys-fs/cryfs:update-check - Enable automatic checking for updates and security vulnerabilities
+sys-fs/cryptsetup:argon2 - Enable password hashing algorithm from app-crypt/argon2
+sys-fs/cryptsetup:gcrypt - Use dev-libs/libgcrypt crypto backend
+sys-fs/cryptsetup:kernel - Use kernel crypto backend (mainly for embedded systems)
+sys-fs/cryptsetup:nettle - Use dev-libs/nettle crypto backend
+sys-fs/cryptsetup:openssl - Use dev-libs/openssl crypto backend
+sys-fs/cryptsetup:pwquality - Use dev-libs/libpwquality for password quality checking
+sys-fs/cryptsetup:reencrypt - Build cryptsetup-reencrypt
+sys-fs/cryptsetup:urandom - Use /dev/urandom instead of /dev/random
+sys-fs/dmraid:dietlibc - Compile against dev-libs/dietlibc
+sys-fs/dmraid:intel_led - Enable Intel LED support
+sys-fs/dmraid:klibc - Compile against dev-libs/klibc
+sys-fs/dmraid:led - Enable LED support
+sys-fs/dmraid:mini - Create a minimal binary suitable for early boot environments
+sys-fs/dosfstools:compat - Install symlinks for legacy names of the tools
+sys-fs/e2fsprogs:fuse - Build fuse2fs, a FUSE file system client for ext2/ext3/ext4 file systems
+sys-fs/ecryptfs-utils:gpg - Enable app-crypt/gnupg key module
+sys-fs/ecryptfs-utils:openssl - Enable dev-libs/openssl key module
+sys-fs/ecryptfs-utils:pkcs11 - Enable PKCS#11 (Smartcards) key module
+sys-fs/ecryptfs-utils:tpm - Enable support for Trusted Platform Module (TPM) using app-crypt/trousers
+sys-fs/eudev:blkid - enable blkid support
+sys-fs/eudev:efi - enable EFI support
+sys-fs/eudev:hwdb - read vendor/device string database and add it to udev database
+sys-fs/eudev:kmod - enable module loading through libkmod
+sys-fs/eudev:rule-generator - install legacy rule generator rules and support scripts - note that the functionality within was dropped from sys-fs/udev as it is not stable in all cases; use at your own risk
+sys-fs/eudev:smack - enable SMACK security model
+sys-fs/ext4magic:expert-mode - Builds ext4magic with expert mode. Highly useful in recovering data from a corrupted filesystem
+sys-fs/ext4magic:file-attr - Enable the recovery of file attributes (append, immutable, nodump etc)
+sys-fs/lessfs:filelog - Enable the ability to log to a file instead of syslog
+sys-fs/lessfs:memtrace - Enable leefs to create a report regarding the memory allocation. This feature should be used for debugging purposes to avoid performance degradation
+sys-fs/lessfs:snappy - Enable snappy compression using the app-arch/snappy library
+sys-fs/loop-aes:cpu_flags_x86_padlock - Use VIA padlock instructions, detected at run time, code still works on non-padlock processors
+sys-fs/loop-aes:extra-ciphers - Enable extra ciphers
+sys-fs/loop-aes:keyscrub - Protects the encryption key in memory but takes more cpu resources
+sys-fs/lvm2:clvm - Allow users to build clustered lvm2
+sys-fs/lvm2:cman - Cman support for clustered lvm
+sys-fs/lvm2:corosync - Corosync support for clustered lvm
+sys-fs/lvm2:device-mapper-only - Build only device-mapper and not the rest of LVM2 (UNSUPPORTED)
+sys-fs/lvm2:lvm1 - Allow users to build lvm2 with lvm1 support
+sys-fs/lvm2:lvm2create_initrd - Install lvm2create_initrd script and pull in sys-apps/makedev for the /sbin/MAKEDEV command
+sys-fs/lvm2:openais - Openais support for clustered lvm
+sys-fs/lvm2:sanlock - Enable lvmlockd with support for sanlock
+sys-fs/lvm2:thin - Support for thin volumes
+sys-fs/mtpfs:mad - Enable handling of MP3's metadata
+sys-fs/multipath-tools:rbd - Enable Rados block device support via sys-cluster/ceph
+sys-fs/ntfs3g:external-fuse - Use external FUSE library instead of internal one. Must be disabled for unprivileged mounting to work.
+sys-fs/ntfs3g:ntfsdecrypt - Build and install the ntfsdecrypt application.
+sys-fs/ntfs3g:ntfsprogs - Include internal version of ntfsprogs.
+sys-fs/ocfs2-tools:external - Enable external locking
+sys-fs/owfs:ftdi - Enable support for USB FTDI chips via dev-embedded/libftdi
+sys-fs/owfs:ftpd - Enable building the OWFS FTP server (owftpd)
+sys-fs/owfs:fuse - Enable building the FUSE-based OWFS client (owfs)
+sys-fs/owfs:httpd - Enable building the OWFS web server (owhttpd)
+sys-fs/owfs:parport - Enable support for the DS1410E parallel port adapter
+sys-fs/owfs:zeroconf - Enables support for zero-configuration networking via net-dns/avahi
+sys-fs/quota:netlink - Compile daemon receiving quota messages via netlink
+sys-fs/quota:rpc - Enable quota interaction via RPC
+sys-fs/squashfs-tools:lz4 - Enable support for LZ4 compression using app-arch/lz4
+sys-fs/squashfs-tools:xz - Enable support for XZ ("LZMA2") compression using app-arch/xz-utils
+sys-fs/squashfs-tools:zstd - Enable support for ZSTD compression using app-arch/zstd
+sys-fs/squashfuse:lz4 - Enable support for lz4 compression
+sys-fs/udev:firmware-loader - Enable the userspace firmware loader (DEPRECATED, replaced by the in-kernel loader starting from 3.8)
+sys-fs/udev:gudev - Build the gobject interface library
+sys-fs/udev:kmod - Enable kernel module loading/unloading support using sys-apps/kmod
+sys-fs/udisks:cryptsetup - Enable sys-fs/cryptsetup support
+sys-fs/udisks:elogind - Use sys-auth/elogind for session tracking
+sys-fs/udisks:gptfdisk - Pull in sys-apps/gptfdisk for sgdisk command as used by partitioning functionality
+sys-fs/udisks:lvm - Add support for Logical Volume Management via sys-fs/lvm2.
+sys-fs/udisks:remote-access - Control whether connections from other clients over LAN are allowed
+sys-fs/udisks:systemd - Support sys-apps/systemd's logind
+sys-fs/zfs:kernel-builtin - Disable dependency on sys-fs/zfs-kmod under the assumption that ZFS is part of the kernel source tree
+sys-fs/zfs:rootfs - Enable dependencies required for booting off a pool containing a rootfs
+sys-fs/zfs:test-suite - Install regression test suite
+sys-fs/zfs-kmod:rootfs - Install zfs-shutdown script to support exporting a pool containing rootfs
+sys-kernel/aufs-sources:experimental - Apply experimental patches; for more information, see "https://wiki.gentoo.org/wiki/Project:Kernel/Experimental".
+sys-kernel/aufs-sources:module - Patch kernel to allow aufs being build as a module.
+sys-kernel/aufs-sources:vanilla - Use vanilla kernel sources without applying genpatches. WARNING: This flag will drop all support from the Gentoo Kernel Security team
+sys-kernel/ck-sources:deblob - Remove binary blobs from kernel sources to provide libre license compliance.
+sys-kernel/ck-sources:experimental - Apply experimental patches; for more information, see "https://wiki.gentoo.org/wiki/Project:Kernel/Experimental".
+sys-kernel/dracut:debug - Module installing additional tools like strace, file editor, ssh and more
+sys-kernel/genkernel:cryptsetup - Enable support for Luks disk encryption using sys-fs/cryptsetup
+sys-kernel/genkernel:firmware - Prefer system firmware sys-kernel/linux-firmware over local copy.
+sys-kernel/genkernel-next:cryptsetup - Enable support for Luks disk enrcyption using sys-fs/cryptsetup
+sys-kernel/genkernel-next:dmraid - Enable support for DMRAID (include dmraid dependency)
+sys-kernel/genkernel-next:gpg - Enable support for GPG (include gnupg dependency)
+sys-kernel/genkernel-next:iscsi - Enable support for open-iscsi (include open-iscsi dependency)
+sys-kernel/genkernel-next:mdadm - Enable support for mdadm (include mdadm dependency)
+sys-kernel/genkernel-next:plymouth - Enable support for Plymouth (include Plymouth dependency)
+sys-kernel/gentoo-sources:experimental - Apply experimental patches; for more information, see "https://wiki.gentoo.org/wiki/Project:Kernel/Experimental".
+sys-kernel/hardened-sources:deblob - Remove binary blobs from kernel sources to provide libre license compliance.
+sys-kernel/linux-docs:html - Install HTML documentation
+sys-kernel/linux-firmware:savedconfig - Allows individual selection of firmware files
+sys-kernel/mips-sources:experimental - Apply experimental (80xx) patches.
+sys-kernel/mips-sources:ip27 - Enables additional support for SGI Origin (IP27)
+sys-kernel/mips-sources:ip28 - Enables additional support for SGI Indigo2 Impact R10000 (IP28)
+sys-kernel/mips-sources:ip30 - Enables support for SGI Octane (IP30, 'Speedracer')
+sys-kernel/rt-sources:deblob - Remove binary blobs from kernel sources to provide libre license compliance.
+sys-libs/binutils-libs:64-bit-bfd - Support 64-bit targets even on 32-bit hosts (is ignored on 64-bit hosts)
+sys-libs/binutils-libs:multitarget - Enable all possible targets in libbfd
+sys-libs/compiler-rt:clang - Force building using installed clang (rather than the default CC/CXX).
+sys-libs/compiler-rt-sanitizers:clang - Force building using installed clang (rather than the default CC/CXX).
+sys-libs/db:rpc - Enable rpc client/server
+sys-libs/freeipmi:nagios - Install a nagios plugin to check sensors' status.
+sys-libs/gdbm:berkdb - enable compatibility layer for UNIX-like dbm and ndbm interfaces
+sys-libs/gdbm:exporter - enable gdbmexport binary for exporting data from gdbm-1.8 databases into gdbm-1.9
+sys-libs/glibc:compile-locales - build *all* locales in src_install; this is generally meant for stage building only as it ignores /etc/locale.gen file and can be pretty slow
+sys-libs/glibc:debug - When USE=hardened, allow fortify/stack violations to dump core (SIGABRT) and not kill self (SIGKILL)
+sys-libs/glibc:gd - build memusage and memusagestat tools
+sys-libs/glibc:nscd - Build, and enable support for, the Name Service Cache Daemon
+sys-libs/glibc:rpc - Enable obsolete RPC/NIS layers
+sys-libs/glibc:suid - Make internal pt_chown helper setuid -- not needed if using Linux and have /dev/pts mounted with gid=5
+sys-libs/glibc:systemtap - enable systemtap static probe points
+sys-libs/gwenhywfar:designer - Build plugins for dev-qt/designer
+sys-libs/gwenhywfar:fox - Use x11-libs/fox graphical toolkit
+sys-libs/gwenhywfar:qml - Enable support for plugins using QML
+sys-libs/gwenhywfar:sensors - Enable support for dev-qt/qtsensors module
+sys-libs/gwenhywfar:serialport - Enable support for dev-qt/qtserialport module
+sys-libs/gwenhywfar:webkit - Enable support for dev-qt/qtwebkit
+sys-libs/libblockdev:bcache - Enable block device cache support.
+sys-libs/libblockdev:cryptsetup - Enable sys-fs/cryptsetup support
+sys-libs/libblockdev:dmraid - Support for dmraid devices, also known as ATA-RAID, or Fake RAID.
+sys-libs/libblockdev:kbd - Enable kernel block device support.
+sys-libs/libblockdev:lvm - Enable support for Logical Volume Management via sys-fs/lvm2.
+sys-libs/libcxx:libcxxabi - Build on top of sys-libs/libcxxabi instead of gcc's libsupc++ (avoids depending on gcc).
+sys-libs/libcxx:libcxxrt - Build on top of sys-libs/libcxxrt instead of gcc's libsupc++ (avoids depending on gcc).
+sys-libs/libcxx:libunwind - Use libunwind instead of libgcc_s for stack unwinding, thus avoiding dependence on gcc.
+sys-libs/libcxxabi:libunwind - Use libunwind instead of libgcc_s for stack unwinding, thus avoiding dependency on gcc
+sys-libs/libcxxrt:libunwind - Use libunwind instead of libgcc_s for unwinding. This should allow avoiding relying on sys-devel/gcc but for now clang is setup to use libgcc_s.
+sys-libs/libhugetlbfs:perl - Install the cpupcstat tool and some perl modules
+sys-libs/libomp:cuda - Build CUDA offloading plugin (only with USE=offload)
+sys-libs/libomp:hwloc - Enable CPU affinity support via hwloc
+sys-libs/libomp:offload - Support offloading OpenMP using libomptarget
+sys-libs/libomp:ompt - Enable OpenMP Tools Interface support
+sys-libs/libselinux:pcre2 - Use dev-libs/libpcre2 for fcontext regexes
+sys-libs/libunwind:debug-frame - Adds support for DWARF .debug_frame section: Use the information from this section if available
+sys-libs/libunwind:libatomic - Use libatomic instead of builtin atomic operations
+sys-libs/musl-nscd:minimal - Only installs the header files
+sys-libs/ncurses:ada - Add bindings for the ADA programming language
+sys-libs/ncurses:tinfo - Build curses library (libncurses) sep from the low-level terminfo library (libtinfo) -- usually needed only for binary packages -- but it is binary compatible in either mode
+sys-libs/ncurses:trace - Enable test trace() support in ncurses calls
+sys-libs/pam:berkdb - Build the pam_userdb module, that allows to authenticate users against a Berkeley DB file. Please note that enabling this USE flag will create a PAM module that links to the Berkeley DB (as provided by sys-libs/db) installed in /usr/lib and will thus not work for boot-critical services authentication.
+sys-libs/pam:cracklib - Build the pam_cracklib module, that allows to verify the chosen passwords' strength through the use of sys-libs/cracklib. Please note that simply enabling the USE flag on this package will not make use of pam_cracklib by default, you should also enable it in sys-auth/pambase as well as update your configuration files.
+sys-libs/readline:utils - Install rlfe (ReadLine Front-End) helper tool -- a wrapper program for making any stdin use readline
+sys-libs/talloc:compat - Enable extra compatibility stuff
+sys-libs/timezone-data:leaps_timezone - Install the set of "right" timezones; these timezones include leap seconds when counting seconds since the epoch (while POSIX does not) as they are based on the TAI (International Atomic Time) clock
+sys-libs/uclibc:rpc - Enable sun nis/rpc support (you should use libtirpc though)
+sys-libs/uclibc:savedconfig - Adds support for user defined configs
+sys-libs/uclibc:ssp - Force the use of ssp to be built into a hardened uclibc setup
+sys-libs/uclibc:uclibc-compat - Build uclibc with backwards compatible options
+sys-libs/uclibc:wordexp - Add support for word expansion (wordexp.h)
+sys-libs/uclibc-ng:rpc - Enable sun nis/rpc support (you should use libtirpc though)
+sys-libs/uclibc-ng:symlink-compat - Explicitly add sym links for libdl.so.0, libm.so.0, and friends for backward compatibility with sys-libs/uclibc-ng-1.0.17 and earlier
+sys-libs/zlib:minizip - include the minizip library for quick and dirty zip extraction
+sys-power/apcupsd:modbus - Enable MODBUS support over USB
+sys-power/cpupower:cpufreq_bench - Build and install the cpufreq_bench binary
+sys-power/nut:ipmi - Support IPMI-based UPSes.
+sys-power/nut:ups_drivers_al175 - Driver for Eltek UPS models with AL175 alarm module
+sys-power/nut:ups_drivers_apcsmart - Driver for American Power Conversion Smart Protocol UPS equipment
+sys-power/nut:ups_drivers_apcsmart-old - Driver for American Power Conversion Smart Protocol UPS equipment
+sys-power/nut:ups_drivers_apcupsd-ups - Driver for apcupsd client access
+sys-power/nut:ups_drivers_bcmxcp - Driver for UPSes supporting the serial BCM/XCP protocol
+sys-power/nut:ups_drivers_bcmxcp_usb - Experimental driver for UPSes supporting the BCM/XCP protocol over USB
+sys-power/nut:ups_drivers_belkin - Driver for Belkin serial UPS equipment
+sys-power/nut:ups_drivers_belkinunv - Driver for Belkin "Universal UPS" and compatible
+sys-power/nut:ups_drivers_bestfcom - Driver for Best Power Fortress/Ferrups
+sys-power/nut:ups_drivers_bestfortress - Driver for old Best Fortress UPS equipment
+sys-power/nut:ups_drivers_bestuferrups - Driver for Best Power Micro-Ferrups
+sys-power/nut:ups_drivers_bestups - Driver for Best Power / SOLA (Phoenixtec protocol) UPS equipment
+sys-power/nut:ups_drivers_blazer_ser - Driver for Megatec/Q1 protocol serial based UPS equipment
+sys-power/nut:ups_drivers_blazer_usb - Driver for Megatec/Q1 protocol USB based UPS equipment
+sys-power/nut:ups_drivers_clone - Fake driver to clone outlets for device grouping
+sys-power/nut:ups_drivers_clone-outlet - Fake driver to clone outlets for device grouping
+sys-power/nut:ups_drivers_dummy-ups - Driver for multi-purpose UPS emulation
+sys-power/nut:ups_drivers_etapro - Driver for ETA UPS equipment
+sys-power/nut:ups_drivers_everups - Driver for Ever UPS models
+sys-power/nut:ups_drivers_gamatronic - Driver for Gamatronic UPS equipment
+sys-power/nut:ups_drivers_genericups - Driver for contact-closure UPS equipment
+sys-power/nut:ups_drivers_isbmex - Driver for ISBMEX UPS equipment
+sys-power/nut:ups_drivers_ivtscd - driver for the IVT Solar Controller Device
+sys-power/nut:ups_drivers_liebert - Driver for Liebert contact-closure UPS equipment
+sys-power/nut:ups_drivers_liebert-esp2 - Driver for Liebert UPS, using the ESP-II serial protocol
+sys-power/nut:ups_drivers_masterguard - Driver for Masterguard UPS equipment
+sys-power/nut:ups_drivers_metasys - Driver for Meta System UPS equipment
+sys-power/nut:ups_drivers_mge-shut - Driver for SHUT Protocol UPS equipment
+sys-power/nut:ups_drivers_mge-utalk - Driver for MGE UPS SYSTEMS UTalk protocol equipment
+sys-power/nut:ups_drivers_microdowell - Driver for Microdowell Enterprise UPS series
+sys-power/nut:ups_drivers_netxml-ups - Driver for Eaton / MGE Network Management Card / Proxy (XML/HTTP Protocol) equipment
+sys-power/nut:ups_drivers_nut-ipmipsu - Driver for IPMI Power Supply Units (PSU)
+sys-power/nut:ups_drivers_nutdrv_qx - Driver for Q* protocol serial and USB based UPS equipment
+sys-power/nut:ups_drivers_oldmge-shut - Driver for SHUT Protocol UPS equipment (older implementation)
+sys-power/nut:ups_drivers_oneac - Driver for Oneac UPS equipment
+sys-power/nut:ups_drivers_optiups - Driver for Opti-UPS (Viewsonic) UPS and Zinto D (ONLINE-USV) equipment
+sys-power/nut:ups_drivers_powercom - UPS driver for serial Powercom/Trust/Advice UPS equipment
+sys-power/nut:ups_drivers_powerpanel - Driver for PowerPanel Plus compatible UPS equipment
+sys-power/nut:ups_drivers_rhino - Driver for Brazilian Microsol RHINO UPS equipment
+sys-power/nut:ups_drivers_richcomm_usb - Driver UPS equipment using Richcomm dry-contact to USB solution
+sys-power/nut:ups_drivers_riello_ser - Driver for Riello UPS Protocol UPS equipment
+sys-power/nut:ups_drivers_riello_usb - Driver for Riello UPS Protocol UPS equipment via USB
+sys-power/nut:ups_drivers_safenet - Driver for SafeNet compatible UPS equipment
+sys-power/nut:ups_drivers_snmp-ups - Multi-MIB Driver for SNMP UPS equipment
+sys-power/nut:ups_drivers_solis - Driver for Brazilian Microsol SOLIS UPS equipment
+sys-power/nut:ups_drivers_tripplite - Driver for Tripp-Lite SmartPro UPS equipment
+sys-power/nut:ups_drivers_tripplite_usb - Driver for older Tripp Lite USB UPSes (not PDC HID)
+sys-power/nut:ups_drivers_tripplitesu - Driver for Tripp-Lite SmartOnline (SU) UPS equipment
+sys-power/nut:ups_drivers_upscode2 - Driver for UPScode II compatible UPS equipment
+sys-power/nut:ups_drivers_usbhid-ups - Driver for USB/HID UPS equipment
+sys-power/nut:ups_drivers_victronups - Driver for IMV/Victron UPS unit Match, Match Lite, NetUps
+sys-power/nvclock:gtk - Install the GTK+ based graphical interface
+sys-power/nvclock:nvcontrol - Add NVCONTROL support for OpenGL options
+sys-power/phctool:sudo - Enable support for sudo to run gui from non-root user
+sys-power/pm-utils:ntp - Install support for net-misc/ntp
+sys-power/powermgmt-base:pm-utils - Adds support for on_ac_power through sys-power/pm-utils
+sys-power/sispmctl:gemplug - Install gemplug (management script)
+sys-power/suspend:crypt - Allows suspend and resume from encrypted disk
+sys-power/suspend:fbsplash - Add support for framebuffer splash
+sys-process/audit:gssapi - Enable GSSAPI support
+sys-process/criu:setproctitle - Make process titles of service workers to be more verbose
+sys-process/cronie:anacron - Install the periodic anacron command scheduler.
+sys-process/cronie:inotify - Enable inotify filesystem monitoring support.
+sys-process/fcron:debug - Enable debug code and output. Since version 3.0.5 this will no longer force foreground execution, and fcron will be able to run as a service properly.
+sys-process/fcron:mta - Enable mta support for sending emails from fcron
+sys-process/fcron:pam - Enable PAM support for fcron. This means that fcron will pass through the "fcron" stack before executing the jobs, and fcrontab will use the "fcrontab" stack to authenticate the user before editing its crontab file.
+sys-process/fcron:system-crontab - Set up fcron to respect /etc/crontab and /etc/cron.d. If this flag is disabled, /etc/cron.d and /etc/crontab will be ignored, but /etc/cron.{hourly,daily,weekly,monthly} will still be respected.
+sys-process/htop:openvz - Enable openvz support
+sys-process/htop:vserver - Enable vserver support
+sys-process/lsof:rpc - support looking up RPC service info
+sys-process/procps:elogind - Use sys-auth/elogind for session tracking.
+sys-process/procps:kill - Build the kill program
+sys-process/procps:modern-top - Enables new startup defaults of top. Keeps old defaults if disabled
+sys-process/procps:ncurses - Build programs that use ncurses: top, slabtop, watch
+sys-process/systemd-cron:cron-boot - Include support for the boot timer.
+sys-process/systemd-cron:etc-crontab-systemd - Use dedicated /etc/crontab-systemd instead of parsing /etc/crontab
+sys-process/systemd-cron:minutely - Support /etc/cron.minutely
+sys-process/systemd-cron:setgid - Compile setgid C helper for crontab. Needs GCC or Clang.
+sys-process/systemd-cron:yearly - Support /etc/cron.yearly
+sys-process/tini:args - Enable argument parsing.
+virtual/ffmpeg:opus - Use the external opus library for encoding and decoding.
+virtual/linux-sources:firmware - Install linux kernel firmware
+virtual/mpi:romio - Enable romio, a high-performance portable MPI-IO
+virtual/mysql:embedded - Build embedded server (libmysqld)
+virtual/mysql:server - Build server (mysqld)
+virtual/podofo-build:boost - Add support for boost
+virtual/podofo-build:tools - Build and install commandline tools.
+virtual/ssh:minimal - Prefer net-misc/dropbear over net-misc/openssh
+virtual/wine:d3d9 - Enable Ixit's Gallium Nine Patchset
+virtual/wine:staging - Enable Wine-Staging's Patchset
+www-apache/mod_backtrace:unwind - Use sys-libs/libunwind to provide better resolution of function names.
+www-apache/mod_extract_forwarded:mod_proxy - Enable support for Apache's internal proxy
+www-apache/mod_musicindex:archive - Add archive support
+www-apache/mod_musicindex:cache - Add File cache support
+www-apache/mod_musicindex:mysql - Add MySQL cache support
+www-apache/mod_nss:ecc - enable Elliptical Curve Cyptography
+www-apache/mod_perl:ithreads - Build for use with thread-capable perl, needs same setting as in dev-lang/perl
+www-apache/mod_security:fuzzyhash - Support fuzzy hash computations (to detect malware, for example) using the app-crypt/ssdeep package.
+www-apache/mod_security:geoip - Pull in dev-libs/geoip for use by the SecGeoLookupDb directive.
+www-apache/mod_security:jit - Add support for the PCRE Just-in-Time optimisation, as enabled by dev-libs/libpcre with jit USE flag enabled. Might not be available on hardened systems.
+www-apache/mod_security:json - Suppose JSON in the request body parser through dev-libs/yajl.
+www-apache/mod_security:mlogc - Build and install the ModSecurity Audit Log Collector (mlogc).
+www-apache/pwauth:domain-aware - Ignore leading domain names in username (Windows compat)
+www-apache/pwauth:faillog - Log failed login attempts
+www-apache/pwauth:ignore-case - Ignore string case in username (mostly Windows compat)
+www-apps/ampache:transcode - Install optional dependencies for transcoding support
+www-apps/blohg:git - Enable Git support
+www-apps/blohg:mercurial - Enable Mercurial support
+www-apps/bugzilla:extras - Optional Perl modules
+www-apps/bugzilla:modperl - Enable www-apache/mod_perl support
+www-apps/cgit:highlight - Enable source code highlighting
+www-apps/cgit:jit - If the lua flag is enabled, jit uses LuaJIT instead of vanilla Lua
+www-apps/cgit:lua - Enable support for Lua scripting
+www-apps/drupal:accelerator - Add dependency on a php accelerator
+www-apps/drupal:uploadprogress - Install dev-php/pecl-uploadprogress package
+www-apps/gitit:network-uri - Get Network.URI from the network-uri package.
+www-apps/gitit:plugins - enables optional plugin runtime loader
+www-apps/guacamole:noauth - enable support for leaving out any authentication on the webinterface
+www-apps/icingaweb2:nginx - Adds support for nginx
+www-apps/ikiwiki:extras - Installs additional modules used by ikiwiki plugins
+www-apps/klaus:ctags - Enable support for Exuberant ctags; makes all source code symbols hyperlinks to their definitions
+www-apps/nikola:assets - Support web asset management through dev-python/assets
+www-apps/nikola:charts - Support chart generation through dev-python/pygal
+www-apps/nikola:ghpages - Add support for direct uploading to github pages thru dev-python/ghp-import
+www-apps/nikola:hyphenation - Add hyphenation support through dev-python/pyphen
+www-apps/nikola:ipython - Add IPython notebook compilation and LESS support
+www-apps/nikola:jinja - Add support for dev-python/jinja as alternative templating engine to Mako
+www-apps/nikola:watchdog - Use dev-python/watchdog to monitor file system events
+www-apps/nikola:webmedia - Use dev-python/micawber to extract metadata from web media links
+www-apps/nikola:websocket - Add websocket support thru dev-python/ws4py
+www-apps/otrs:mod_perl - Provide all dependencies for use of mod_perl instead of cgi
+www-apps/postfixadmin:vacation - Install vacation.pl script and dependencies
+www-apps/redmine:markdown - Enable support for Markdown
+www-apps/redmine:passenger - Enable support for www-apache/passenger
+www-apps/rt:lighttpd - Add www-servers/lighttpd support
+www-apps/sitebar:plugins - Install optional plugins
+www-apps/sugarcrm:json - Add JSON (JavaScript Object Notation) support
+www-apps/trac:highlight - Enable syntax highlighting
+www-apps/trac:i18n - Enable support for i18n with dev-python/Babel
+www-apps/trac:restructuredtext - Enable support for reStructuredText for wiki formatting
+www-apps/tt-rss:daemon - Install additional init scripts for automated RSS updates
+www-apps/venus:django - Support for django template style to config files
+www-apps/venus:genshi - Support for genshi style to config files
+www-apps/venus:redland - Enable support for Redland RDF
+www-apps/viewvc:cvsgraph - Add dev-vcs/cvsgraph support to show graphical views of revisions and branches
+www-apps/viewvc:mod_wsgi - Add www-apache/mod_wsgi support
+www-apps/viewvc:pygments - Add dev-python/pygments support for syntax highlighting
+www-apps/webdavcgi:rcs - Adds support for a revision controlled backend with RCS (dev-vcs/rcs)
+www-apps/wordpress:akismet - Installs Akismet comment spam plug-in
+www-apps/wordpress:themes - Installs themes (including default theme)
+www-client/chromium:component-build - Split build into more shared libraries to speed up linking. Mostly intended for debugging and development, NOT RECOMMENDED for general use.
+www-client/chromium:hangouts - Enable support for Google Hangouts features such as screen sharing
+www-client/chromium:jumbo-build - Combine source files to speed up build process.
+www-client/chromium:pic - Disable optimized assembly code that is not PIC friendly
+www-client/chromium:proprietary-codecs - Enable proprietary codecs like H.264, MP3
+www-client/chromium:suid - Build the SUID sandbox, which is only needed on CONFIG_USER_NS=n kernels
+www-client/chromium:system-ffmpeg - Use system ffmpeg instead of the bundled one
+www-client/chromium:system-icu - Use system icu instead of the bundled one
+www-client/chromium:system-libvpx - Use system libvpx instead of the bundled one
+www-client/chromium:tcmalloc - Use bundled tcmalloc instead of system malloc
+www-client/chromium:widevine - Unsupported closed-source DRM capability (required by Netflix VOD)
+www-client/elinks:bittorrent - Enable support for the BitTorrent protocol
+www-client/elinks:brotli - Enable support for brotli compression
+www-client/elinks:finger - Enable support for the finger protocol
+www-client/elinks:gc - Enable garbage collection support via dev-libs/boehm-gc
+www-client/elinks:gopher - Enable support for the gopher protocol
+www-client/elinks:mouse - Make elinks to grab all mouse events
+www-client/elinks:tre - Enable support for regex searches via dev-libs/tre
+www-client/elinks:xml - Enable support for bookmarks via dev-libs/expat
+www-client/falkon:kwallet - Enable encrypted storage of passwords with kde-frameworks/kwallet
+www-client/firefox:bindist - Disable official Firefox branding (icons, name) which are not binary-redistributable according to upstream.
+www-client/firefox:custom-optimization - Build with user-specified compiler optimizations (-Os, -O0, -O1, -O2, -O3) from CFLAGS (unsupported)
+www-client/firefox:eme-free - Disable EME (DRM plugin) cabability at build time
+www-client/firefox:gmp-autoupdate - Allow Gecko Media Plugins (binary blobs) to be automatically downloaded and kept up-to-date in user profiles
+www-client/firefox:gtk2 - Use the cairo-gtk2 rendering engine
+www-client/firefox:hwaccel - Force-enable hardware-accelerated rendering (Mozilla bug 594876)
+www-client/firefox:jemalloc - Enable or disable jemalloc
+www-client/firefox:pgo - Add support for profile-guided optimization using gcc-4.5, for faster binaries. This option will double the compile time.
+www-client/firefox:rust - Enable support for using rust compiler (experimental)
+www-client/firefox:screenshot - Allow to disable screenshot extension in global profile
+www-client/firefox:system-cairo - Use the system-wide x11-libs/cairo instead of bundled.
+www-client/firefox:system-harfbuzz - Use the system-wide media-libs/harfbuzz and media-gfx/graphite2 instead of bundled.
+www-client/firefox:system-icu - Use the system-wide dev-libs/icu instead of bundled.
+www-client/firefox:system-jpeg - Use the system-wide media-libs/libjpeg-turbo instead of bundled.
+www-client/firefox:system-libevent - Use the system-wide dev-libs/libevent instead of bundled.
+www-client/firefox:system-libvpx - Use the system-wide media-libs/libvpx instead of bundled.
+www-client/firefox:system-sqlite - Use the system-wide dev-db/sqlite installation with secure-delete enabled
+www-client/google-chrome:plugins - Add system plugins path to launcher
+www-client/google-chrome-beta:plugins - Add system plugins path to launcher
+www-client/google-chrome-unstable:plugins - Add system plugins path to launcher
+www-client/links:libevent - Enable dev-libs/libevent support
+www-client/luakit:luajit - Use dev-lang/luajit instead of dev-lang/lua
+www-client/lynx:gnutls - Use gnutls library for HTTPS support (openssl is the default library for HTTPS support).
+www-client/lynx:ssl - Enable HTTPS support.
+www-client/midori:granite - Enable support for the elementary library dev-libs/granite
+www-client/midori:zeitgeist - Add support for Zeitgeist event tracking system
+www-client/netsurf:bmp - BMP bitmap image support (media-libs/libnsbmp)
+www-client/netsurf:duktape - Use duktape.org javascript engine
+www-client/netsurf:fbcon_frontend_able - Use framebuffer frontend able
+www-client/netsurf:fbcon_frontend_linux - Use framebuffer frontend linux
+www-client/netsurf:fbcon_frontend_sdl - Use framebuffer frontend sdl
+www-client/netsurf:fbcon_frontend_vnc - Use framebuffer frontend vnc
+www-client/netsurf:fbcon_frontend_x - Use framebuffer frontend X
+www-client/netsurf:gtk - Build GTK GUI, defaults to GTK3
+www-client/netsurf:gtk2 - Build GTK2 GUI
+www-client/netsurf:gtk3 - Build GTK3 GUI
+www-client/netsurf:pdf-writer - PDF output support (media-libs/libharu)
+www-client/netsurf:psl - Use public suffix list via media-libs/libnspsl
+www-client/netsurf:rosprite - RISC OS Sprite bitmap image support (media-libs/librosprite)
+www-client/netsurf:svgtiny - SVG image support via media-libs/svgatiny instead of gnome-base/librsvg
+www-client/netsurf:webp - WebP image support (media-libs/libwebp)
+www-client/opera:gtk - Install support libraries and runtime dependencies to support GTK+/GNOME desktop integration
+www-client/otter:webengine - Use dev-qt/qtwebengine as backend instead of dev-qt/qtwebkit (experimental)
+www-client/qupzilla:kwallet - Enable encrypted storage of passwords with kde-frameworks/kwallet
+www-client/qupzilla:nonblockdialogs - Enable fancy non-blocking JavaScript dialogs shown inside the page, not blocking the application window. When closing browser windows with open dialogs, this can crash the application.
+www-client/seamonkey:calendar - Build Mozilla's calendar
+www-client/seamonkey:chatzilla - Build Mozilla's IRC client (default on)
+www-client/seamonkey:custom-optimization - Build with user-specified compiler optimizations (-Os, -O0, -O1, -O2, -O3) from CFLAGS (unsupported)
+www-client/seamonkey:force-gtk3 - Use the cairo-gtk3 rendering engine
+www-client/seamonkey:gmp-autoupdate - Allow Gecko Media Plugins (binary blobs) to be automatically downloaded and kept up-to-date in user profiles
+www-client/seamonkey:ipc - Use inter-process communication between tabs and plugins. Allows for greater stability in case of plugin crashes
+www-client/seamonkey:jemalloc - Enable or disable jemalloc
+www-client/seamonkey:roaming - Build roaming extension support (default on)
+www-client/seamonkey:system-cairo - Use the system-wide x11-libs/cairo instead of bundled
+www-client/seamonkey:system-harfbuzz - Use the system-wide media-libs/harfbuzz instead of bundled
+www-client/seamonkey:system-icu - Use the sytem-wide dev-libs/icu instead of bundled
+www-client/seamonkey:system-jpeg - Use the system-wide media-libs/libjpeg-turbo instead of bundled
+www-client/seamonkey:system-libevent - Use the system-wide dev-libs/libevent instead of bundled
+www-client/seamonkey:system-libvpx - Use the system-wide media-libs/libvpx instead of bundled
+www-client/seamonkey:system-sqlite - Use the system-wide dev-db/sqlite installation with secure-delete enabled
+www-client/surf:savedconfig - Without a saved config.h, this package depends on net-misc/curl and x11-terms/st for a default download mechanism
+www-client/uget:aria2 - Enable support for net-misc/aria2 through xmlrpc. You'll find the plugin in the app's settings.
+www-client/uget:control-socket - Enable JSON-RPC over unix domain socket
+www-client/uget:gtk3 - Use x11-libs/gtk+:3 instead of x11-libs/gtk+:2
+www-client/uget:hide-temp-files - Make temporary files that are used while downloading hidden.
+www-client/uget:openssl - Use dev-libs/openssl instead of net-libs/gnutls
+www-client/uget:rss - Enable uGet feed messages
+www-client/w3m:lynxkeymap - If you prefer Lynx-like key binding
+www-client/weboob:deprecated - Enable dev-python/mechanize support (deprecated in favor of dev-python/requests
+www-client/weboob:fast-libs - Enable fast libs
+www-client/weboob:secure-updates - Enable secure updates
+www-misc/gurlchecker:json - Enable support for parsing Google Chrome and derivatives bookmarks.
+www-misc/gurlchecker:sqlite - Enable support for parsing Firefox and derivatives bookmarks.
+www-misc/litmus:libproxy - Support for automatic proxy configuratino management through net-libs/libproxy.
+www-misc/litmus:libxml2 - Use dev-libs/libxml2 to parse XML
+www-misc/litmus:pkcs11 - Support for PKCS #11 through PaKChoiS (dev-libs/pakchois).
+www-misc/monitorix:apcupsd - Make use of a daemon that controls APC UPSes with sys-power/apcupsd.
+www-misc/monitorix:httpd - Enables the CGI webserver with any package that satisfies virtual/httpd-cgi.
+www-misc/monitorix:postfix - Analyze postfix logs with net-mail/pflogsumm.
+www-misc/shellinabox:pam - Enable PAM support.
+www-misc/vdradmin-am:vdr - Support for media-video/vdr. Disable this if the VDR you want to control runs at a remote machine.
+www-misc/xxv:themes - Enable more themes via x11-themes/xxv-skins
+www-misc/zoneminder:curl - Enable using net-misc/curl for streaming from cameras
+www-misc/zoneminder:gcrypt - ...
+www-misc/zoneminder:vlc - Enable using media-libs/vlc for streaming from cameras
+www-plugins/adobe-flash:nsplugin - Install the Netscape Flash API plugin (for Firefox and similar browsers)
+www-plugins/adobe-flash:ppapi - Install the Pepper Flash API plugin (for Chrome and similar browsers)
+www-plugins/chrome-binary-plugins:widevine - Install the Widevine DRM library
+www-plugins/freshplayerplugin:gles2 - Use system GLESv2 libraries instead of ANGLE for shader translation
+www-plugins/freshplayerplugin:gtk3 - Build with GTK+ 3 instead of GTK+ 2
+www-plugins/freshplayerplugin:v4l - Use libv4l2 for colorspace conversion
+www-plugins/gnash:agg - Rendering based on the Anti-Grain Geometry Rendering Engine library
+www-plugins/gnash:cygnal - Enable building of the cygnal server
+www-plugins/gnash:dump - Enable dump output module for creating video from SWF
+www-plugins/gnash:egl - Enable EGL support for the OpenVG, OpenGL and X11 renderers
+www-plugins/gnash:harden - Enable upstream recommended hardening build flags (may conflict with system ones)
+www-plugins/gnash:jemalloc - Use dev-libs/jemalloc for allocations
+www-plugins/gnash:openvg - Rendering based on the OpenVG graphics acceleration API
+www-plugins/gnash:sdl-sound - Enable SDL audio output for the standalone player
+www-plugins/gnash:ssh - Enable using SSH for network authentication in libnet
+www-plugins/gnash:ssl - Enable directly using OpenSSL in libnet (not needed for nsplugin ssl support)
+www-plugins/lightspark:gles - Replace default OpenGL renderer with GLESv2
+www-plugins/lightspark:ppapi - Install the PPAPI plugin (for Chromium)
+www-plugins/lightspark:rtmp - Enable Real Time Messaging Protocol using librtmp
+www-servers/apache:apache2_modules_access_compat - Group authorizations based on host (name or IP address). Available as a compatibility module with previous versions.
+www-servers/apache:apache2_modules_authn_core - Provides core authentication capabilities common to all authentication providers (functionality provided by authn_alias in previous versions).
+www-servers/apache:apache2_modules_authz_core - Provides core authorization capabilities to various authorization/authorization modules, such as authn_file and authz_user.
+www-servers/apache:apache2_modules_authz_dbd - Provides authorization capabilities via SQL database so that authenticated users can be allowed or denied access to portions of the web site by group membership.
+www-servers/apache:apache2_modules_brotli - Enable brotli compression support
+www-servers/apache:apache2_modules_cache_disk - Disk based storage module for the HTTP caching filter (similar to mem_cache in previous versions).
+www-servers/apache:apache2_modules_cache_socache - Shared object cache (socache) based storage module for the HTTP caching filter.
+www-servers/apache:apache2_modules_http2 - Enable http2/alpn module
+www-servers/apache:apache2_modules_lbmethod_bybusyness - Pending request counting load balancer scheduler algorithm for proxy_balancer.
+www-servers/apache:apache2_modules_lbmethod_byrequests - Request counting load balancer scheduler algorithm for proxy_balancer.
+www-servers/apache:apache2_modules_lbmethod_bytraffic - Weighted traffic counting load balancer scheduler algorithm for proxy_balancer.
+www-servers/apache:apache2_modules_lbmethod_heartbeat - Heartbeat traffic counting load balancer scheduler algorithm for proxy_balancer.
+www-servers/apache:apache2_modules_macro - Macros for the Apache config file.
+www-servers/apache:apache2_modules_proxy_fcgi - FCGI support module for mod_proxy.
+www-servers/apache:apache2_modules_proxy_html - Module to rewrite links in html pages behind a reverse proxy
+www-servers/apache:apache2_modules_proxy_wstunnel - Provides support for the tunnelling of web socket connections to a backend websockets server.
+www-servers/apache:apache2_modules_ratelimit - Ratelimit module for transfer rate management
+www-servers/apache:apache2_modules_remoteip - Remotip module for logging
+www-servers/apache:apache2_modules_slotmem_shm - Slot-based shared memory provider.
+www-servers/apache:apache2_modules_socache_shmcb - A shared object cache provider using a high-performance cyclic buffer inside a shared memory segment.
+www-servers/apache:apache2_modules_unixd - Basic (required) security for Unix-family platforms.
+www-servers/apache:apache2_modules_watchdog - Provides infrastructure for other modules to periodically run tasks
+www-servers/apache:apache2_modules_xml2enc - Enable xml2 encoding module
+www-servers/apache:static - Link in apache2 modules statically rather then plugins
+www-servers/apache:suexec - Install suexec with apache
+www-servers/cherokee:admin - Install web based cherokee conf tool
+www-servers/cherokee:rrdtool - Enable rrdtool support
+www-servers/fnord:auth - Enable HTTP authentication support
+www-servers/gatling:diet - Compile against dev-libs/dietlibc
+www-servers/h2o:mruby - Enable support for mruby
+www-servers/hiawatha:cache - Enable caching of content
+www-servers/hiawatha:monitor - Pull in www-apps/hiawatha-monitor
+www-servers/hiawatha:rewrite - Enable the rewrite toolkit
+www-servers/hiawatha:rproxy - Enable reverse proxy support
+www-servers/hiawatha:ssl - Enable TLS support via net-libs/mbedtls
+www-servers/hiawatha:tomahawk - Enable Tomahawk control server
+www-servers/hiawatha:xslt - Enable XSLT support. This is also needed for directory listings
+www-servers/lighttpd:libev - Enable fdevent handler
+www-servers/lighttpd:mmap - Use mmap with files owned by lighttpd. This is a dangerous option as it may allow local users to trigger SIGBUS crashes.
+www-servers/lighttpd:rrdtool - Enable rrdtool support via mod_rrdtool
+www-servers/lighttpd:webdav - Enable webdav properties
+www-servers/monkeyd:debug - Enable lots of debugging info
+www-servers/monkeyd:static-plugins - Build statically linked plugins
+www-servers/nginx:aio - Enables file AIO support
+www-servers/nginx:http - Enable HTTP core support
+www-servers/nginx:http-cache - Enable HTTP cache support
+www-servers/nginx:http2 - Enable HTTP2 module support
+www-servers/nginx:libatomic - Use libatomic instead of builtin atomic operations
+www-servers/nginx:luajit - Use dev-lang/luajit instead of dev-lang/lua for lua support when building the lua http module.
+www-servers/nginx:pcre-jit - Enable JIT for pcre
+www-servers/nginx:rtmp - NGINX-based Media Streaming Server
+www-servers/nginx:ssl - Enable HTTPS module for http. Enable SSL/TLS support for POP3/IMAP/SMTP for mail.
+www-servers/pound:dynscaler - Enable dynamic rescaling of back-end priorities
+www-servers/pshs:magic - Enable automatic detection of Content-Type using libmagic (sys-apps/file)
+www-servers/pshs:netlink - Use libnetlink (sys-apps/iproute2) to get network interface addresses
+www-servers/pshs:qrcode - Enable generating QRCodes for server URL
+www-servers/resin:admin - Enable Resin admin webapp
+www-servers/sniproxy:dns - Enable DNS resolver via net-libs/udns
+www-servers/sniproxy:largefile - Enable large file support (so we can log more than 2GB)
+www-servers/sniproxy:rfc3339 - Use RFC3339 timestamp format in log.
+www-servers/tomcat:extra-webapps - Build also the docs and examples webapp
+www-servers/tomcat:websockets - Builds websockets api and implementation (requires java 7)
+www-servers/uwsgi:embedded - Embed plugins instead of building them as real plugins. When disabling this USE flag make sure you specify all used plugins in your uWSGI configuration. Note: Language plugins will always be built as real plugins.
+www-servers/uwsgi:go - Build the gccgo plugin to run Go applications.
+www-servers/uwsgi:jemalloc - Use dev-libs/jemalloc instead of libc's malloc
+www-servers/uwsgi:json - Support json as a configuration file format.
+www-servers/uwsgi:pypy - Build the pypy plugin to run your code using virtual/pypy.
+www-servers/uwsgi:python_asyncio - Use the EXPERIMENTAL asyncio (tulip) for python3.4 async request dispatching and as LoopEngine (see http://uwsgi-docs.readthedocs.org/en/latest/asyncio.html).
+www-servers/uwsgi:python_gevent - Use dev-python/gevent for async request dispatching and as LoopEngine (see http://projects.unbit.it/uwsgi/wiki/Gevent).
+www-servers/uwsgi:routing - Enable routing support
+www-servers/uwsgi:yajl - Use dev-libs/yajl instead of dev-libs/jansson for parsing JSON configuration files (if USe=json is set)
+www-servers/uwsgi:yaml - Support yaml as a configuration file format.
+www-servers/uwsgi:zeromq - Enable logging and deployment via ZeroMQ.
+www-servers/varnish:jemalloc - Use dev-libs/jemalloc for allocations
+www-servers/xsp:developer - creates .mdb files for either Release and Debug
+www-servers/xsp:net35 - use .NET 3.5 Framework
+www-servers/xsp:net40 - use .NET 4.0 Framework
+www-servers/xsp:net45 - use .NET 4.5 Framework
+x11-apps/copyq:webkit - enables the application to use advanced HTML rendering and fetching remote images and other data
+x11-apps/intel-gpu-tools:glib - Support reading config files via glib helpers
+x11-apps/intel-gpu-tools:test-programs - Install test programs for DRM driver development
+x11-apps/intel-gpu-tools:unwind - Provide automatic stack traces on test failures
+x11-apps/intel-gpu-tools:valgrind - Support valgrind annotations
+x11-apps/intel-gpu-tools:xrandr - Enable support for the X RandR extension
+x11-apps/mesa-progs:egl - Build EGL utilities
+x11-apps/mesa-progs:gles2 - Build OpenGL ES 2 utilities
+x11-apps/xdm:consolekit - Enable native sys-auth/consolekit support
+x11-apps/xdm:xdm-auth - Enable XDM-AUTHENTICATION-1 support
+x11-apps/xdpyinfo:dmx - Builds support for Distributed Multiheaded X x11-base/xorg-server
+x11-apps/xinit:minimal - Control dependencies on legacy apps (xterm, twm, ...). Safe to enable if you use a modern desktop environment.
+x11-apps/xsm:rsh - This allows the use of rsh (remote shell) and rcp (remote copy).
+x11-base/xorg-server:dmx - Build the Distributed Multiheaded X server
+x11-base/xorg-server:glamor - Enable Glamor OpenGL 2D acceleration
+x11-base/xorg-server:kdrive - Build the kdrive X servers
+x11-base/xorg-server:tslib - Build with tslib support for touchscreen devices
+x11-base/xorg-server:unwind - Enable libunwind usage for backtraces
+x11-base/xorg-server:xcsecurity - Build Security extension
+x11-base/xorg-server:xephyr - Build the Xephyr server
+x11-base/xorg-server:xnest - Build the Xnest server
+x11-base/xorg-server:xorg - Build the Xorg X server (HIGHLY RECOMMENDED)
+x11-base/xorg-server:xvfb - Build the Xvfb server
+x11-drivers/nvidia-drivers:X - Install the X.org driver, OpenGL libraries, XvMC libraries, and VDPAU libraries
+x11-drivers/nvidia-drivers:compat - Install non-GLVND libGL for backwards compatibility
+x11-drivers/nvidia-drivers:driver - Install the kernel driver module
+x11-drivers/nvidia-drivers:gtk3 - Install nvidia-settings with support for GTK+ 3
+x11-drivers/nvidia-drivers:kms - Enable support for kernel mode setting (KMS)
+x11-drivers/nvidia-drivers:pax_kernel - PaX patches from the PaX project
+x11-drivers/nvidia-drivers:tools - Install additional tools such as nvidia-settings
+x11-drivers/nvidia-drivers:uvm - Install the Unified Memory kernel module (nvidia-uvm) for sharing memory between CPU and GPU in CUDA programs
+x11-drivers/xf86-video-ati:glamor - Enable Glamor OpenGL 2D acceleration
+x11-drivers/xf86-video-geode:ztv - Enable building the V4L2 ZTV driver
+x11-drivers/xf86-video-intel:dri3 - Use DRI3 by default
+x11-drivers/xf86-video-intel:sna - Enable SandyBridge's New Acceleration (useful on all chipsets, not just SandyBridge)
+x11-drivers/xf86-video-intel:tools - Build the intel-virtual-output tool
+x11-drivers/xf86-video-intel:uxa - Enable UMA Acceleration Architecture
+x11-drivers/xf86-video-intel:xvmc - Enables X-Video Motion Compensation support
+x11-drivers/xf86-video-openchrome:viaregtool - Install registers dumper tool
+x11-drivers/xf86-video-qxl:xspice - Build the xspice driver
+x11-libs/agg:gpc - Enable gpc polygon clipper library
+x11-libs/cairo:gles2 - Build the OpenGL ES 2 backend
+x11-libs/cairo:glib - Compile with GLib Object System support
+x11-libs/cairo:opengl - Build the OpenGL backend
+x11-libs/cairo:utils - Build support for Cairo script and trace utilities
+x11-libs/cairo:valgrind - Built-in support to mark memory regions
+x11-libs/fltk:games - Builds and installs some extra games
+x11-libs/gdk-pixbuf:X - Build and install the legacy gdk_pixbuf_xlib-2.0 library
+x11-libs/gtk+:broadway - Enable the GDK Broadway backend.
+x11-libs/gtk+:cloudprint - Enable printing via Google Cloud Print.
+x11-libs/gtk+:colord - Use x11-misc/colord for color management in printing
+x11-libs/gtkdatabox:glade - Build with libglade and glade-3 supports, which includes a glade's module for GtkDataBox widget
+x11-libs/gtkmathview:mathml - Install additional fonts for proper mathml support.
+x11-libs/gtkmathview:t1lib - Enable media-libs/t1lib support
+x11-libs/gtksourceview:glade - Install a glade catalog file
+x11-libs/libQGLViewer:designer - Installs dev-qt/designer plugin.
+x11-libs/libSM:uuid - Use UUID for session identification instead of IP address and system time.
+x11-libs/libXaw:deprecated - Install deprecated Xaw6 library.
+x11-libs/libXfont:bzip2 - Support bzip2 compressed PCF fonts.
+x11-libs/libXfont:truetype - Use media-libs/freetype for font rasterization.
+x11-libs/libXfont2:bzip2 - Support bzip2 compressed PCF fonts.
+x11-libs/libXfont2:truetype - Use media-libs/freetype for font rasterization.
+x11-libs/libaosd:pango - Enable the textual helpers (requires pangocairo).
+x11-libs/libaosd:tools - Install the aosd_cat tool (requires glib-2.0).
+x11-libs/libdesktop-agnostic:gconf - Enable GConf as configuration backend
+x11-libs/libdesktop-agnostic:glade - Install the Glade catalog for the desktop-agnotstic GTK widgets.
+x11-libs/libdrm:libkms - Enable building of libkms, a library for applications to interface with KMS
+x11-libs/libdrm:valgrind - Compile in valgrind memory hints
+x11-libs/libfm:automount - Use gnome-base/gvfs for automounting
+x11-libs/libfm:udisks - Use libfm's udisks-based volume monitor implementation instead of using the one from gvfs
+x11-libs/libfm:vala - Support custom actions in menus
+x11-libs/libqxt:berkdb - Build the QxtBerkeley module
+x11-libs/libqxt:sql - Build the QxtSql module
+x11-libs/libqxt:web - Build the QxtWeb module
+x11-libs/libqxt:zeroconf - Build the QxtZeroconf module
+x11-libs/libva:drm - Enables VA/DRM API support.
+x11-libs/libva:egl - Enables EGL support.
+x11-libs/libva:utils - Install VA-API utility programs.
+x11-libs/libva-intel-driver:drm - Enables VA/DRM API support.
+x11-libs/libwnck:tools - Install wnckprop-3 and wnck-urgency-monitor-3 command-line tools
+x11-libs/libxcb:xkb - Enable the XCB keyboard extension
+x11-libs/motif:motif22-compatibility - Compatibility with Open Motif 2.2
+x11-libs/pango:X - Build and install the legacy pangoxft library
+x11-libs/pixman:loongson2f - Enable Loongson2f MMI optimizations.
+x11-libs/qscintilla:designer - Build plugin for Qt Designer
+x11-libs/qwt:designer - Installs dev-qt/designer plugin.
+x11-libs/qwt:mathml - Use the MathML renderer of the Qt solutions package.
+x11-libs/vte:glade - Provide integration with dev-util/glade.
+x11-libs/wxGTK:gnome - Use gnome-base/libgnomeprintui for printing tasks.
+x11-libs/wxGTK:gstreamer - Enable the wxMediaCtrl class for playing audio and video through gstreamer.
+x11-libs/wxGTK:sdl - Use Simple Directmedia Layer (media-libs/libsdl) for audio.
+x11-misc/alock:doc - Build and install manpage with app-text/asciidoc.
+x11-misc/bumblebee:bbswitch - Add dependency on sys-power/bbswitch for PM feature
+x11-misc/cdm:consolekit - Enable native consolekit support
+x11-misc/colord:argyllcms - Enable ArgyllCMS sensor
+x11-misc/colord:extra-print-profiles - Generate extra print profiles. Warning: significant build time and memory requirements.
+x11-misc/colord:gusb - Enable dev-libs/libgusb support, needed for colorimeter drivers
+x11-misc/compton:drm - Enable VSync with DRM_IOCTL_WAIT_VBLANK
+x11-misc/compton:opengl - Enable VSync with SGI_swap_control OpenGL extension
+x11-misc/dunst:dunstify - Experimental replacement for notify-send.
+x11-misc/fbpager:xrender - Enable transparency support via x11-libs/libXrender
+x11-misc/gpaste:applet - Enable gpaste-applet
+x11-misc/gpaste:gnome - Enable proper gnome support and enable gnome shell extension.
+x11-misc/gtkdialog:glade - Enable support for gnome-base/libglade
+x11-misc/gtkdialog:vte - Enable support for x11-libs/vte
+x11-misc/i3status:filecaps - Linux capabilities library is required for i3status to be able to read net bandwith
+x11-misc/ktsuss:sudo - Use the sudo backend instead the su one
+x11-misc/light-locker:consolekit - Keep track of the various users, sessions, and seats present on the system.
+x11-misc/light-locker:dpms - Turn on the display on screensaver deactivation.
+x11-misc/light-locker:gtk3 - Build with GTK+ 3 instead of GTK+ 2.
+x11-misc/light-locker:screensaver - Lock the screen on screensaver activation.
+x11-misc/lightdm:gtk - Pull in the gtk+ greeter
+x11-misc/mate-notification-daemon:gtk3 - Build with GTK+3 instead of GTK+2
+x11-misc/mozo:gtk3 - Build with GTK+3 instead of GTK+2
+x11-misc/openbox-menu:icons - Enable support for icons in menus
+x11-misc/openbox-menu:svg - Support SVG icons
+x11-misc/qt5ct:dbus - Enable system tray and global menu support
+x11-misc/qt5ct:systray - Enable system tray support
+x11-misc/redshift:appindicator - Enable usage of dev-libs/libappindicator to export menu options in to unity and KDE 5
+x11-misc/redshift:geoclue - Control dependency on app-misc/geoclue
+x11-misc/rofi:windowmode - Enable normal window mode
+x11-misc/rss-glx:quesoglc - Enable support for OpenGL Character Renderer
+x11-misc/sddm:consolekit - Use ck-launch-session from sys-auth/consolekit by default in Xsession (no native support)
+x11-misc/sddm:elogind - Use sys-auth/elogind for session tracking.
+x11-misc/sent:savedconfig - Without a saved config.h, this package depends on media-gfx/farbfeld for image conversions
+x11-misc/shutter:drawing - Enables drawing tool
+x11-misc/slim:consolekit - Enable native consolekit support
+x11-misc/spacefm:gtk2 - Support GTK+ 2.x instead of GTK+ 3.x
+x11-misc/spacefm:gtk3 - Support GTK+ 3.x instead of GTK+ 2.x
+x11-misc/spacefm:video-thumbnails - Support video thumbnails with media-video/ffmpegthumbnailer
+x11-misc/stalonetray:graceful-exit - use non-portable hack to exit gracefuly on signal
+x11-misc/tint2:battery - Enable battery status plugin
+x11-misc/tint2:tint2conf - Build/Install tint2conf as well
+x11-misc/vnc2swf:x11vnc - Install script that depends on x11vnc
+x11-misc/wbar:gtk - Enables the gtk-based wbar-config GUI
+x11-misc/xkbset:tk - Install the dev-perl/Tk based xkbset-gui utility
+x11-misc/xlockmore:vtlock - Enables support for virtual terminal locking
+x11-misc/xlockmore:xlockrc - Enables xlockrc for people without PAM
+x11-misc/xmobar:mpd - Support mpd plugin
+x11-misc/xmobar:mpris - Enables MPRIS v1, v2 support
+x11-misc/xmobar:timezone - Enables localized date support
+x11-misc/xmobar:with_conduit - Use conduit to fetch weather data.
+x11-misc/xmobar:with_uvmeter - Plugin to show UV data for Australia.
+x11-misc/xscreensaver:gdm - Use gdmflexiserver from gnome-base/gdm instead of x11-misc/lightdm
+x11-misc/xscreensaver:new-login - Enable user switching support using gdmflexiserver (x11-misc/lightdm)
+x11-misc/xsr:cursor - Capture mouse cursor using x11-misc/xdotool, and place them on the screenshots using media-gfx/imagemagick
+x11-misc/xss-lock:man - Build and install man pages
+x11-plugins/bfm:gkrellm - Enable building of app-admin/gkrellm module
+x11-plugins/pidgin-mbpurple:twitgin - Enable graphical plugin for Gtk+ interface of Pidgin.
+x11-plugins/pidgin-sipe:ocs2005-message-hack - Disable message timeout for OCS2005 clients which causes "false" not delivered error messages
+x11-plugins/pidgin-sipe:openssl - Enable crypto support via dev-libs/openssl
+x11-plugins/pidgin-sipe:telepathy - Support use as a telepathy backend
+x11-plugins/pidgin-sipe:voice - Enable experimental voice/video support
+x11-plugins/purple-plugin_pack:talkfilters - Enable support for app-text/talkfilters
+x11-plugins/vicious:contrib - Install extra widgets, some for less common hardware, some contributed by Vicious users.
+x11-plugins/wmfire:session - Enable session management
+x11-terms/aterm:background - Enable background image support via media-libs/libafterimage
+x11-terms/aterm:xgetdefault - Enable resources via X instead of aterm small version
+x11-terms/eterm:escreen - Enable built-in app-misc/screen support
+x11-terms/eterm:utempter - Include libutempter support
+x11-terms/gnome-terminal:gnome-shell - Integrate with gnome-base/gnome-shell search
+x11-terms/gnome-terminal:nautilus - Build gnome-base/nautilus extension
+x11-terms/hanterm:utempter - Records user logins. Useful on multi-user systems
+x11-terms/kitty:imagemagick - Support displaying images in the terminal with icat
+x11-terms/mate-terminal:gtk3 - Build with GTK+3 instead of GTK+2
+x11-terms/mlterm:fcitx - Enable support for app-i18n/fcitx
+x11-terms/mlterm:gtk2 - Build with x11-libs/gtk+:2 instead of x11-libs/gtk+:3
+x11-terms/mlterm:harfbuzz - Enable support for OpenType Layout (media-libs/harfbuzz)
+x11-terms/mlterm:ibus - Enable support for app-i18n/ibus
+x11-terms/mlterm:libssh2 - Enable support for net-libs/libssh2
+x11-terms/mlterm:regis - Enable support for ReGIS
+x11-terms/mlterm:scim - Enable support for app-i18n/scim
+x11-terms/mlterm:skk - Enable support for SKK (virtual/skkserv or app-i18n/skk-jisyo)
+x11-terms/mlterm:uim - Enable support for app-i18n/uim
+x11-terms/mlterm:utempter - Enable support for sys-libs/libutempter
+x11-terms/mrxvt:menubar - Enable mrxvt menubar
+x11-terms/mrxvt:utempter - REcords user logins. Useful on multi-user systems
+x11-terms/rxvt-unicode:256-color - Enable 256 color support
+x11-terms/rxvt-unicode:alt-font-width - Calculate the font width using a different method
+x11-terms/rxvt-unicode:blink - Enable blinking text
+x11-terms/rxvt-unicode:buffer-on-clear - Store visible output to history buffer when clearing the screen with ctrl-l. Read https://bbs.archlinux.org/viewtopic.php?id=129302
+x11-terms/rxvt-unicode:fading-colors - Enable colors fading when off focus
+x11-terms/rxvt-unicode:focused-urgency - Enable the urgent flag when a terminal window is focused
+x11-terms/rxvt-unicode:font-styles - Enable support for bold and italic fonts
+x11-terms/rxvt-unicode:iso14755 - Enable ISO-14755 support
+x11-terms/rxvt-unicode:mousewheel - Enable scrolling via mouse wheel or buttons 4 and 5
+x11-terms/rxvt-unicode:perl - Enable perl script support. You can still disable this at runtime with -pe ""
+x11-terms/rxvt-unicode:pixbuf - Enable transparency support using gtk's pixbuf
+x11-terms/rxvt-unicode:secondary-wheel - Support for wheel scrolling on secondary screens (like mutt). Read http://lists.schmorp.de/pipermail/rxvt-unicode/2011q4/001491.html
+x11-terms/rxvt-unicode:unicode3 - Use 21 instead of 16 bits to represent unicode characters
+x11-terms/rxvt-unicode:wcwidth - Enable wide char width support
+x11-terms/terminator:libnotify - Enables desktop notifications viadev-python/notify-python
+x11-terms/xfce4-terminal:utempter - Include utmp management support via sys-libs/libutempter
+x11-terms/xterm:openpty - Use openpty() in preference to posix_openpt()
+x11-terms/xterm:toolbar - Enable the xterm toolbar to be built
+x11-themes/arc-theme:cinnamon - Install theme for gnome-extra/cinnamon
+x11-themes/arc-theme:gnome-shell - Install theme for gnome-base/gnome-shell
+x11-themes/arc-theme:gtk2 - Install GTK+2 theme
+x11-themes/arc-theme:gtk3 - Install GTK+3 theme
+x11-themes/arc-theme:mate - Install Metacity theme for mate-base/mate
+x11-themes/arc-theme:xfce - Install theme for xfce-base/xfwm4
+x11-themes/comix-xcursors:lefthanded - Install lefthanded version of theme in addition to default one
+x11-themes/comix-xcursors:opaque - Install non-transparent version of theme in addition to default one
+x11-themes/gentoo-artwork:grub - Install extra sys-boot/grub themes
+x11-themes/gentoo-artwork:icons - Install icons
+x11-themes/gentoo-artwork:lilo - Install extra sys-boot/lilo themes
+x11-themes/gentoo-artwork:pixmaps - Install pixmaps
+x11-themes/gtk-engines-murrine:animation-rtl - Progressbar animation from right to left
+x11-themes/gtk-engines-murrine:themes - Pull in themes via x11-themes/murrine-themes
+x11-themes/gtk-engines-nodoka:animation-rtl - Progressbar animation from right to left
+x11-themes/kfaenza:additional - Install additional KFaenza icons. See third homepage for details
+x11-themes/light-themes:gtk3 - Support GTK 3.x, too
+x11-themes/mate-themes-meta:gtk2-only - Allow dependency-resolution for a system without GTK+3
+x11-themes/redhat-artwork:audacious - Install media-sound/audacious theme
+x11-themes/redhat-artwork:cursors - Install Bluecurve cursors
+x11-themes/redhat-artwork:gdm - Install Bluecurve gnome-base/gdm theme
+x11-themes/redhat-artwork:icons - Install Bluecurve icons
+x11-themes/redhat-artwork:nautilus - Install Bluecurve gnome-base/nautilus icons
+x11-themes/skinenigmang-logos:dxr3 - Install logos for lower osd color depth on dxr3 cards
+x11-themes/vertex-theme:cinnamon - Install theme for gnome-extra/cinnamon
+x11-themes/vertex-theme:gnome-shell - Install theme for gnome-base/gnome-shell
+x11-themes/vertex-theme:mate - Install Metacity theme for mate-base/mate
+x11-themes/vertex-theme:xfce - Install theme for xfce-base/xfwm4
+x11-themes/zuki-themes:gnome-shell - Install theme for gnome-base/gnome-shell
+x11-themes/zuki-themes:mate - Install Metacity theme for mate-base/mate
+x11-themes/zuki-themes:xfce - Install theme for xfce-base/xfwm4
+x11-themes/zukitwo:gnome-shell - Install theme for gnome-base/gnome-shell
+x11-wm/awesome:luajit - Use dev-lang/luajit instead of dev-lang/lua
+x11-wm/echinus:xrandr - Enable support for multihead configuration
+x11-wm/enlightenment:enlightenment_modules_appmenu - Gadget that hold the toolbar of the foreground application
+x11-wm/enlightenment:enlightenment_modules_backlight - Backlight control slider gadget
+x11-wm/enlightenment:enlightenment_modules_battery - A gadget to visualize your battery status
+x11-wm/enlightenment:enlightenment_modules_bluez4 - Configure Bluetooth devices
+x11-wm/enlightenment:enlightenment_modules_clock - Nice clock gadget to show current time
+x11-wm/enlightenment:enlightenment_modules_conf - Settings Panel
+x11-wm/enlightenment:enlightenment_modules_conf-applications - Allows configuration of Ibar, Restart, and Startup applications
+x11-wm/enlightenment:enlightenment_modules_conf-bindings - Input Control Settings
+x11-wm/enlightenment:enlightenment_modules_conf-dialogs - Configure default dialog properties
+x11-wm/enlightenment:enlightenment_modules_conf-display - Used to configure your screen
+x11-wm/enlightenment:enlightenment_modules_conf-interaction - Configure Mouse and Touch input
+x11-wm/enlightenment:enlightenment_modules_conf-intl - Used to select a default language
+x11-wm/enlightenment:enlightenment_modules_conf-menus - Configures menu behavior
+x11-wm/enlightenment:enlightenment_modules_conf-paths - Specifies the Enlightenment search paths and default directories
+x11-wm/enlightenment:enlightenment_modules_conf-performance - Used to configure certain performance related items as frame rates and cache settings
+x11-wm/enlightenment:enlightenment_modules_conf-randr - Used to configure your screen's resolution
+x11-wm/enlightenment:enlightenment_modules_conf-shelves - Shelf configuration dialog
+x11-wm/enlightenment:enlightenment_modules_conf-theme - Used to configure your theme preferences
+x11-wm/enlightenment:enlightenment_modules_conf-window-manipulation - Configures window raise, resistance, and maximize policies
+x11-wm/enlightenment:enlightenment_modules_conf-window-remembers - Delete existing window remembers
+x11-wm/enlightenment:enlightenment_modules_connman - Control Wifi and wired networks as a user
+x11-wm/enlightenment:enlightenment_modules_cpufreq - Gadget to monitor and change the CPU frequency
+x11-wm/enlightenment:enlightenment_modules_everything - The run command module provides an application launcher dialog
+x11-wm/enlightenment:enlightenment_modules_fileman - Enlightenment's integrated file manager
+x11-wm/enlightenment:enlightenment_modules_fileman-opinfo - Can be placed on the desktop or in a shelf
+x11-wm/enlightenment:enlightenment_modules_gadman - Module to manage gadgets on the desktop
+x11-wm/enlightenment:enlightenment_modules_geolocation - Geolocation
+x11-wm/enlightenment:enlightenment_modules_ibar - Iconic application launcher
+x11-wm/enlightenment:enlightenment_modules_ibox - A home for your iconified applications
+x11-wm/enlightenment:enlightenment_modules_lokker - Screen locker
+x11-wm/enlightenment:enlightenment_modules_mixer - A module to provide a mixer for changing volume
+x11-wm/enlightenment:enlightenment_modules_msgbus - DBus Extension
+x11-wm/enlightenment:enlightenment_modules_music-control - Control your music in your shelf
+x11-wm/enlightenment:enlightenment_modules_notification - notification-daemon alternative. Popup if an event occur
+x11-wm/enlightenment:enlightenment_modules_packagekit - Package manager integration
+x11-wm/enlightenment:enlightenment_modules_pager - Gadget to allow you to visualize your virtual desktops and the windows they contain
+x11-wm/enlightenment:enlightenment_modules_pager-plain - A simpler desktop pager
+x11-wm/enlightenment:enlightenment_modules_quickaccess - Enlightenment Quickaccess Launcher
+x11-wm/enlightenment:enlightenment_modules_shot - Simple screenshot+save/upload module
+x11-wm/enlightenment:enlightenment_modules_start - Enlightenment's 'Start' button equivalent
+x11-wm/enlightenment:enlightenment_modules_syscon - This module provides a unified popup dialog for all the system actions in Enlightenment
+x11-wm/enlightenment:enlightenment_modules_systray - system tray that hold applications icons like Skype, Pidgin, Kopete and others
+x11-wm/enlightenment:enlightenment_modules_tasks - Gadget to allow you to switch tasks
+x11-wm/enlightenment:enlightenment_modules_teamwork - Enable teamwork module
+x11-wm/enlightenment:enlightenment_modules_temperature - Temperature monitor
+x11-wm/enlightenment:enlightenment_modules_tiling - Positions/resizes your windows tilingly
+x11-wm/enlightenment:enlightenment_modules_time - Time related gadgets
+x11-wm/enlightenment:enlightenment_modules_winlist - A module to show the list of client applications presently running
+x11-wm/enlightenment:enlightenment_modules_wireless - WiFi monitoring
+x11-wm/enlightenment:enlightenment_modules_wizard - First Run Wizard
+x11-wm/enlightenment:enlightenment_modules_wl-desktop-shell - Enlightenment Wayland Desktop Shell
+x11-wm/enlightenment:enlightenment_modules_wl-drm - Wayland DRM (Direct Rendering Manager) compositing module
+x11-wm/enlightenment:enlightenment_modules_wl-text-input - Wayland text input support
+x11-wm/enlightenment:enlightenment_modules_wl-weekeyboard - Wayland virtual keyboard
+x11-wm/enlightenment:enlightenment_modules_wl-wl - Wayland-in-Wayland module
+x11-wm/enlightenment:enlightenment_modules_wl-x11 - Wayland-in-X11 module
+x11-wm/enlightenment:enlightenment_modules_xkbswitch - Keyboard layout configuration and switcher
+x11-wm/enlightenment:enlightenment_modules_xwayland - X/Wayland integration
+x11-wm/enlightenment:pango - Enable pango font rendering
+x11-wm/enlightenment:ukit - Use upower/udisks to automount devices
+x11-wm/enlightenment:xrandr - Enable support for the X xrandr extension
+x11-wm/fluxbox:bidi - Enable bidirectional language support with dev-libs/fribidi
+x11-wm/fluxbox:slit - Enables the Fluxbox slit (or dock)
+x11-wm/fluxbox:systray - Enables the system tray in the Fluxbox toolbar
+x11-wm/fluxbox:toolbar - Enables the Fluxbox toolbar
+x11-wm/fvwm:gtk2-perl - Enable GTK2 Perl bindings
+x11-wm/fvwm:lock - Enable screen locking
+x11-wm/fvwm:netpbm - Enable NetPBM support (used by FvwmScript-ScreenDump)
+x11-wm/fvwm:rplay - Enable rplay support
+x11-wm/fvwm:stroke - Mouse Gesture support
+x11-wm/i3:doc - Build and install the HTML documentation and regenerate the man pages
+x11-wm/lumina:desktop-utils - Build and install lumina's desktop-utils
+x11-wm/marco:gtk3 - Build with GTK+3 instead of GTK+2
+x11-wm/musca:apis - Optionally install the experimental `apis' window manager
+x11-wm/musca:xlisten - Optionally install the xlisten utility
+x11-wm/mutter:gles2 - Enable OpenGL ES 2.0 support
+x11-wm/notion:xrandr - Add support for xrandr
+x11-wm/openbox:session - Enables support for session managers
+x11-wm/openbox:xdg - Install the python xdg files for xdg autostart
+x11-wm/pekwm:contrib - Install optional extras in the documentation directory
+x11-wm/pekwm:themes - Install additional themes
+x11-wm/ratpoison:history - Use sys-libs/readline for history handling
+x11-wm/ratpoison:sloppy - Install sloppy, a focus-follows-mouse implementation for ratpoison
+x11-wm/ratpoison:xrandr - Enable support for XRandR
+x11-wm/stumpwm:contrib - Install contrib modules
+x11-wm/stumpwm:doc - Include documentation
+x11-wm/stumpwm:emacs - Add support for GNU Emacs
+x11-wm/subtle:xrandr - Enable support for the X RandR extension
+x11-wm/subtle:xtest - Enable support for the XTest extension
+x11-wm/vtwm:rplay - Enable rplay support, needed for sound.
+x11-wm/windowmaker:modelock - Enable XKB language status lock support. README says: "If you don't know what it is you probably don't need it."
+x11-wm/windowmaker:webp - Enables WebP image format support using media-libs/libwebp
+x11-wm/windowmaker:xrandr - Enable XRandR window extension support
+x11-wm/wmfs:imlib2 - Enable image support through media-libs/imlib2
+x11-wm/xmonad:default-term - Pull terminal specified in default xmonad config to be a bit less hostile by default.
+x11-wm/xmonad:no-autorepeat-keys - Allow ignoring of keyboard autorepeat.
+x11-wm/xpra:client - Build client-side code
+x11-wm/xpra:clipboard - Enable clipboard support
+x11-wm/xpra:csc - Enable csc softscaler support
+x11-wm/xpra:dec_avcodec2 - Enable avcodec2 decoder support
+x11-wm/xpra:enc_ffmpeg - Enable advanced ffmpeg/libav encoder support
+x11-wm/xpra:enc_x264 - Enable x264 encoder support
+x11-wm/xpra:enc_x265 - Enable x265 encoder support
+x11-wm/xpra:lz4 - Enable support for lz4 compression
+x11-wm/xpra:pillow - Enable pillow support
+x11-wm/xpra:server - Build server-side code
+x11-wm/xpra:vpx - Enable vpx image format support
+x11-wm/xpra:webcam - Enable webcam support via opencv
+x11-wm/xpra:webp - Enable webp image format support
+xfce-base/garcon:gtk2 - Build the garcon-gtk2-1 library (required for xfce-base/xfce4-panel < 4.13 only).
+xfce-base/libxfce4ui:glade - Build support for Glade 3's GtkBuilder implementation
+xfce-base/thunar:trash-panel-plugin - Build the trash status indicator plugin for the XFCE panel
+xfce-base/xfce4-settings:libcanberra - Enable sound event support using media-libs/libcanberra
+xfce-base/xfce4-settings:xklavier - Enable keyboard layout selection support using x11-libs/libxklavier
+xfce-base/xfdesktop:thunar - Build support for desktop icons (for example, launchers and folders)
+xfce-base/xfwm4:xpresent - Enable the XPresent extension for sync to vblank
+xfce-extra/tumbler:odf - Enable support for .odf thumbnailers by using gnome-extra/libgsf
+xfce-extra/xfce4-clipman-plugin:qrcode - Enable support for media-gfx/qrencode
+xfce-extra/xfce4-mpc-plugin:libmpd - Build using media-libs/libmpd backend, instead of native fallback which is preferred
+xfce-extra/xfce4-playercontrol-plugin:audacious - Enable Audacious support
+xfce-extra/xfce4-playercontrol-plugin:mpd - Enable Music Player Daemon support
+xfce-extra/xfce4-power-manager:panel-plugin - Build the power management plugin for the XFCE panel
+xfce-extra/xfce4-pulseaudio-plugin:keybinder - Enable support for global hotkeys using dev-libs/keybinder.
+xfce-extra/xfce4-pulseaudio-plugin:wnck - Enable experimental support for raising media player windows using x11-libs/libwnck.
+xfce-extra/xfce4-soundmenu-plugin:glyr - Enable music metadata searchengine support using media-libs/glyr
+xfce-extra/xfce4-soundmenu-plugin:keybinder - Enable shortcut support using dev-libs/keybinder
+xfce-extra/xfce4-soundmenu-plugin:lastfm - Enable last.fm support using media-libs/libclastfm
+xfce-extra/xfce4-taskmanager:gksu - Build against x11-libs/libgksu to provide "Run as root" option in the application's menu
+xfce-extra/xfce4-taskmanager:gtk3 - Use GTK+3 instead of GTK+2
+xfce-extra/xfswitch-plugin:gdm - Compatibility with gnome-base/gdm only
+xfce-extra/xfswitch-plugin:lightdm - Compatibility with x11-misc/lightdm only
+xfce-extra/xfswitch-plugin:lxdm - Compatibility with lxde-base/lxdm only