Universal Plug and Play Software Development Kit

http://pupnp.sourceforge.net/

D-Bus daemon for simplifying power management tasks

http://upower.freedesktop.org/

Ultimate Packer for eXecutables

https://upx.github.io/ https://github.com/upx/upx

URI parsing library

https://github.com/uriparser/uriparser

URL extractor/launcher

https://github.com/sigpipe/urlview

URW core35 fonts in various formats

https://www.ghostscript.com

Another font package for X

Unicode TrueType fonts from URW extended by Valek Filippov

Database of all known IDs used in USB devices

http://www.linux-usb.org/

Daemon for multiplexing connections over USB to iPhone/iPod Touch

https://www.libimobiledevice.org

Simple, portable, lightweight library for handling UTF-8 strings

https://github.com/nemtrif/utfcpp

UTF-8 processing library

https://juliastrings.github.io/utf8proc/

hash table for C structures

http://uthash.sourceforge.net/

Kernel driver for absolute USB HID mice

https://github.com/wulf7/utouch

Program for uu/xx/Base64/BinHex/yEnc de-/encoding

http://www.fpx.de/fp/Software/UUDeview/

Library for uu/xx/Base64/BinHex/yEnc de-/encoding

http://www.fpx.de/fp/Software/UUDeview/

Monospaced bitmap fonts for X11

https://people.mpi-inf.mpg.de/~uwe/misc/uw-ttyp0/

V Programming Language

https://vlang.io/ https://github.com/vlang/v

Video4Linux utilities

https://linuxtv.org/wiki/index.php/V4l-utils

Video4Linux IOCTL header files

https://linuxtv.org

Implementation of the UNIX 7th Edition shell

http://minnie.tuhs.org/UnixTree/V7/

Open source JavaScript engine by Google

https://v8.dev/

Programming language and compiler that converts Vala code into C code

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

Memory debugging and profiling tool

https://www.valgrind.org/

Markup Validation Service from the World Wide Web Consortium (W3C)

https://validator.w3.org/

High-performance data structure server that primarily serves key/value workloads

https://valkey.io/

Vamp audio analysis plugin SDK

https://www.vamp-plugins.org/

Video processing framework with simplicity in mind

https://www.vapoursynth.com/

High-performance HTTP accelerator

http://www.varnish-cache.org/

High-performance HTTP accelerator

https://varnish-cache.org/

Open source Gameboy Advance emulator

http://vba.ngemu.com/

GNU VCDImager/VCDRip -- The GNU VideoCD Image Maker/Ripping Tool

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

User-mode virtual ethernet infrastructure

https://github.com/virtualsquare/vde-2

Merchant Of Venice, a stock market trading program

https://mov.sourceforge.net/

PCB (printed circuit board) design software

https://sourceforge.net/projects/veroroute/

Virtual Ethernet Interface

https://github.com/hmatyschok/if_vether

Nintendo GameBoy(tm) emulator (closed binary version of vgb)

https://fms.komkon.org/VGB/

Synchronize DNS with server names and aliases from Apache vhost

https://man.gnu.org.ua/manpage/?1+vhostcname

Emulator for Commodore C64, C128, VIC20, PET, and CBM-II

https://vice-emu.sourceforge.io/

Programming font with cursive italics and ligatures

https://rubjo.github.io/victor-mono/

Fast and simple image viewer

https://siyanpanayotov.com/project/viewnior/

Graphical class browser for Xt

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

Web-based Version Control Repository Browsing

https://www.viewvc.org/

VIGRA stands for "Vision with Generic Algorithms"

https://ukoethe.github.io/vigra/

Improved version of the vi editor (x11 flavor)

https://www.vim.org/

VNC client for the GNOME Desktop

http://www.gnome.org/projects/vinagre/

VNC server that allows for remote access to your GNOME desktop

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

Toolkit to interact with virtualization capabilities

https://virt-manager.org/

Provides a graphical viewer for a guest OS display

https://virt-manager.org/

VirtualBox additions for FreeBSD guests

https://www.virtualbox.org/