GNOME keyboard shared library

Toolkit based on glib and ncurses for text-mode user interfaces

https://keep.imfreedom.org/libgnt/libgnt/

Common error values for all GnuPG components

https://www.gnupg.org/software/libgpg-error/

Universal digital camera control library

http://www.gphoto.org/proj/libgphoto2/

Library for direct access to iPod/iPhone contents

http://www.gtkpod.org/wiki/Libgpod

Library for easy management of RSS/Atom/Pie feeds

http://www.gnome.org/

GNU SASL library

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

Extensible i/o abstraction for dealing with structured file formats

http://www.gnumeric.org

GNOME top library

https://gitlab.gnome.org/GNOME/libgtop

GObject bindings for libudev.

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

Library to access online weather informations

http://www.gnome.org/

GObject based library for rendering XPS documents

https://wiki.gnome.org/action/show/Projects/libgxps

Library with GTK+ widgets for mobile phones

https://gitlab.gnome.org/GNOME/libhandy/

Library with GTK+ widgets for mobile phones

https://source.puri.sm/Librem5/libhandy

HTML5 parser library

https://www.netsurf-browser.org/projects/hubbub/

Implementation of the IETF Calendaring and Scheduling protocols

https://github.com/libical

Character set conversion library

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

ID3 tags library (part of MAD project)

http://mad.sourceforge.net/

Internationalized Domain Names command line tool

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

Implementation of IDNA2008 internationalized domain names

https://www.gnu.org/software/libidn/#libidn2 https://gitlab.com/libidn/libidn2

C library that supports plugin printer driver for Ghostscript

http://www.linuxprinting.org/ijs/

Library to communicate with Apple iOS devices

http://www.libimobiledevice.org

Kevent based inotify compatible library

https://github.com/libinotify-kqueue/libinotify-kqueue

Generic input library

https://www.freedesktop.org/wiki/Software/libinput/

ODBC 3.x driver manager, for universal data source access

http://www.iodbc.org/

Library for manipulating IPTC metadata stored in image files

http://libiptcdata.sourceforge.net/

Library for Evation's Irman infrared receiver

https://libirman.sourceforge.io/

Standalone client/server 9P library

https://libs.suckless.org/deprecated/libixp/

Codec for karaoke and text encapsulation for Ogg

https://wiki.xiph.org/index.php/OggKate

Library to make X.509 certificates

https://www.gnupg.org/aegypten2/

Interface library to access tags for identifying languages

http://tagoh.bitbucket.org/liblangtag/

Lightweight Open Sound Control implementation

http://liblo.sourceforge.net/

Standard lockfile library

https://github.com/miquels/liblockfile

Easy to use C/C++ seam carving library

http://liblqr.wikidot.com/

System independent dlopen wrapper

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

LZ4 compression library, lossless and very fast

http://www.lz4.org/

Libmad library (part of MAD project)

https://www.underbit.com/products/mad/

MATE keyboard shared library

https://mate-desktop.org/

Mixer library for MATE desktop

https://github.com/mate-desktop/libmatemixer

Library to accessing online weather informations

https://mate-desktop.org/

Extensible Multimedia Container Format

https://www.matroska.org/

Library for the MaxMind DB file format used for GeoIP2

https://github.com/maxmind/libmaxminddb

Multi-cipher cryptographic library (used in PHP)

http://mcrypt.sourceforge.net/

Library for handling media art

https://www.gnome.org/

C library for accessing a memcache cluster

https://people.FreeBSD.org/~seanc/libmemcache/

C and C++ client library to the memcached server

http://libmemcached.org

Set of utilities to benchmark productivity of system calls

http://hub.opensolaris.org/bin/view/Project+libmicro/

MikMod Sound Library

http://mikmod.sourceforge.net/

Library providing Sendmail Mail Filter API

http://www.sendmail.com/sm/open_source/milter/

Multiple-image Network Graphics (MNG) reference library

https://www.libmng.com/