C++ wrapper for Gtk+3

http://gtkmm.sourceforge.net/

GTK+ UI debugging tool

http://chipx86.github.com/gtkparasite/

Measure your system's GTK+ performance

http://gtkperf.sourceforge.net

2D pool game using the GTK+ toolkit

http://gtkpool.seul.org/

Widget that adds syntax highlighting to the GtkTextView widget

Widget that adds syntax highlighting to GtkTextView

Text widget that adds syntax highlighting to the GtkTextView widget

https://wiki.gnome.org/Projects/GtkSourceView/

Programming reference for x11-toolkits/gtksourceview3

A GTK+ 2 spell checking component

http://gtkspell.sourceforge.net/

GTK+ 3 spell checking component

http://gtkspell.sourceforge.net/

Interactive typing tutor

http://www.gnu.org/software/gtypist/

Unicode/ISO10646 character map and font viewer

https://wiki.gnome.org/Gucharmap

GNU Ubiquitous Intelligent Language for Extension

https://www.gnu.org/software/guile/

GutenPrint Printer Driver

http://gimp-print.sourceforge.net/

PostScript and PDF previewer

http://www.gnu.org/software/gv/

GNOME virtual file system

https://www.gnome.org/

GNUstep workspace manager

http://www.gnustep.it/enrico/gworkspace/

GWMetadata for GNUstep workspace manager

http://www.gnustep.it/enrico/gworkspace/

Compression utility designed to be a replacement for compress

http://www.gnu.org/software/gzip/

gzip recovery toolkit

https://www.urbanophile.com/arenn/hacking/gzrt/

Hardware Abstraction Layer for simplifying device access

http://www.freedesktop.org/Software/hal

Additional FDI files to further classify HAL devices

http://www.freedesktop.org/Software/hal

Library of matchers for building test expressions

http://hamcrest.org/

OpenType text shaping engine

https://harfbuzz.github.io/

Anti-spam / denial of service counter-measure tool

http://www.hashcash.org/

Hierarchical Data Format library (from NCSA)

https://www.hdfgroup.org/

Automatically generating simple manual pages from program output

https://www.gnu.org/software/help2man/

Online help viewer for GNUstep programs

http://www.roard.com/helpviewer/

High-color icon theme shell from the FreeDesktop project

http://www.freedesktop.org/Standards/icon-theme-spec

Customizable syntax highlighter

http://www.andre-simon.de/

Framework needed by Project Manager

http://home.gna.org/pmanager/

Utility primarily designed to find the owner of an IP block

Small utility which displays the system activity in a very special way

http://dindinx.net/hotbabe/

Network auditing tool

http://www.hping.org/

Hebrew spellchecker and morphology engine

http://hspell.ivrix.org.il

All W3C published SGML DTDs for HTML

Converts HTML documents into plain text

http://www.mbayer.de/html2text/

Time synchronization over http utility

http://www.vervest.org/htp/

Tool for measuring webserver performance

https://github.com/httperf/httperf

Improved spell-checker for Hungarian and other languages

https://hunspell.github.io/

Library for building UPnP devices and control points

http://hupnp.linada.fi/

Portable Hardware Locality software package

http://www.open-mpi.org/projects/hwloc/

Library for high quality hyphenation and justification

https://github.com/hunspell/hyphen

32bit Microsoft Windows compatibility environment for 64bit BSD

http://www.winehq.org/

IA64 simulator (Intel(R) Architecture 64)

http://www.boo.net/~jasonp/

Restricted unix shell

http://ibsh.sourceforge.net/

Intelligent Input Bus for Unix-like systems

https://github.com/ibus/ibus

ICE authority file utility for X

Window Manager designed for speed, usability and consistency

https://ice-wm.org/

Displays a wire-frame rotating plyhedron

https://gitlab.freedesktop.org/xorg/app/ico