Free 32/64/16-bit multi-platform Pascal and Object Pascal compiler
A 32/64/16-bit Pascal compiler for Win32/64/CE, Linux, Mac OS X/iOS, FreeBSD, OS/2, Game Boy Advance, Nintendo NDS and DOS; semantically compatible with Delphi, Borland Pascal and Mac Pascal (partially) with extra features, e.g. operator overloading.
Open Source Solid Modeling CAD
BRL-CAD is a powerful cross-platform constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing for rendering & geometric analyses, network distributed framebuffer support, image & signal-processing tools.
gPhoto is a program and library framework that lets users download pictures from their digital cameras. The libgphoto2 library gives you access to hundreds of models of digital cameras on several platforms. GIT repo and Issue tracker lives at https://github.com/gphoto/ these days.
ANSI C functions and macros for flexible logging to files and other destinations. It is modeled after the Log for Java library (http://www.log4j.org), staying as close to their API as is reasonable. Intended for use in time-space critical environments
The PHP script engine for Java. --- Run PHP applications within any J2EE server or servlet engine and/or connect script engines like PHP with Java or .NET back ends efficiently.
The Heirloom Project provides standard Unix utilities.
libircclient is a small but powerful library, which implements client-server IRC protocol. It has all features needed to create your own IRC client or bot, including multi-threading support, sync and async interfaces, CTCP/DCC support, colors, SSL connections and so on.
The OSALP is a C++ class library that contains everything one needs to build an audio application. It contains a powerful chaining concept so programmers can build an audio application by selecting the building blocks they need.
Twin is a "retro" program for embedded or remote systems
Twin is a text-mode window environment. It supports mouse and multiple windows, has a built-in terminal emulator and window manager, and can serve as display for client applications. Its retro look-and-feel comes with very modern features: it is best described as a VNC-like server, that can use a variety of displays - all with mouse support: from a plain text terminal, to a Linux console, to a full kde, gnome or X11 desktop. Source code hosted at https://github.com/cosmos72/twin
A lightweight cross platform IP telephony client using the IAX protocol, designed for use with the asterisk open source PBX.
pam_mount is a Pluggable Authentication Module that can mount volumes for a user session (login). Supports mounting local filesystems of any kind the normal mount utility supports, with extra code to better support CIFS, FUSE, various crypto, and more.
Leafnode is a caching Usenet news proxy that enables online newsreaders to read news off-line and aggregates news from various NNTP servers into one. It is designed for full-automatic maintenance, and IPv6 enabled.
A canvas library for generating technical drawings
The ADG library (Automatic Drawing Generation) is a set of functions focused on automating the drawing of mechanical parts. It is not a CAD system but a GObject-based library where a custom application can put common CAD entities such as paths, hatches and dimensions, to automatically create technical drawings. A demo application is provided in order to show the capabilities of the canvas. Although it is possible to interact with the library directly in C (that is what the adg-demo program is doing), the canvas is expected to be used from higher level languages, much in the same way as what done in the GNOME stack. Lua bindings based on LGI are already provided out of the box. The adg-lua project, downloadable from the "Files" section, provides Lua programs and demos that leverages these bindings.
2D/3D Scene Graph rendering engine for Linux/Unix/Win32 layered atop OpenGL. Supports stereoscopy, volume rendering, 2D/3D texture mapping, picking, LOD and view-dependent operations, cross-platform text, constant-rate rendering and image-based data.
libivykis is a thin wrapper over various OS'es implementation of I/O readiness notification facilities (such as poll(2), kqueue(2)) and is mainly intended for writing portable high-performance network servers.
The DCHK project contains a client implementation of RFC 5144 in C/C++, which can be used to check the availability of domains. It is divided into a C/C++ library, a command line client and a GUI.
MyServer development has moved to GNU savannah since it became an official GNU Project: https://savannah.gnu.org/projects/myserver
Some Useful C-Utilities
Libcutils provides a self-contained set of fundamental routines which are essential to basically any Unix utility or daemon application written in C. The library provides fundamental data structures such as lists, hash-maps, strings and parsing functions for JSON or the typical dot-file based configuration data. The following list summarizes the currently supported functionality: * length delimited instead of NULL terminated strings * memory management based on reference counting * several list processing functions like iterators and map-reduce * support of [Ideal Hash Tries](http://infoscience.epfl.ch/record/64398/files/idealhashtrees.pdf) for highly efficient hash map data structures * parsers for [JSON](http://json.org) data and the text configuration files found in Unix system * doubly linked circular lists for reliable event queues * support for test and debugging of memory management problems such as memory leaks
Open-source, cross-platform 3D rendering engine for .NET and Mono. The Axiom Engine is a high-performance C# port of the powerful OGRE engine and provides full support for DirectX, OpenGL and XNA on Windows, Linux, Android, iPhone and Windows Phone.
A C++ based XML loader and writer with an internal DOM representation. It is very lightweight and high-performance. The goal of this project is to provide a lightweight C++ interface for XML programming that is similar in API and functionality to JDOM.
ttyrpld is a multi-OS kernel-level TTY keylogger and screenlogger with (a)synchronous replay support. It runs on Linux, Solaris, FreeBSD, NetBSD and OpenBSD.
Tools for a mail delivery service, including LMTP and POP3 servers and also getpwnam() emulation. Mail is stored in Maildir++ format (qmail plus courier extensions as soft quota and subfolders). User defined filter and virtual domains are supported.
Python FAM provides a Python module to use the File Alteration Monitor (http://oss.sgi.com/projects/fam) in Python.
High-performance transactional memory for Common Lisp
STMX is a high-performance Common Lisp library for composable Transactional Memory (TM), a concurrency control mechanism aimed at making concurrent programming easier to write and understand. Instead of traditional lock-based programming, one programs with atomic memory transactions: if a memory transaction returns normally it gets committed, if instead it signals an error (Lisp slang for throwing an exception) it is rolled back. Memory transactions can safely run in parallel in different threads, are re-executed from the beginning in case of conflicts or if consistent reads cannot be guaranteed, and effects of a transaction are not visible from other threads until it commits. STMX gives freedom from deadlocks, automatic rollback on failure, and it aims at resolving the tension between granularity and concurrency.
VR Juggler is a virtual platform for virtual reality application development created at the Virtual Reality Applications Center at Iowa State University. Applications developed in VR Juggler can transparently move between a wide range of VR systems.