Library for Posting Electronic Mail: manages posting email using SMTP to a preconfigured MTA. Can be used as part of a Mail User Agent or other program that must post email. Free: GNU LGPL.

The URARFileLib is a platform-independent, small and fast static library for decompressing RAR files (RAR archives are created with WinRAR). Full RAR v2.0 file format support of all compression methods, including multimedia compression and encoding.

Collections of mathematical software in Fortan and C. Software is free for some uses and can be purchased for others. Much of the software was developed at the Jet Propulsion Laboratory.

An easy to use library that allows programmers to integrate fingerprint technology into their software without specific know-how. Fast, easy to use, and small; great for embedded systems. [Open source, MPL]

By iMatix Corp., portable function library for C/C++ programs; many years development; written in ANSI C; ports: DOS, OpenVMS, OS/2, most Unix, Windows; full sources and documentation (HTML); given as Open Source software for the benefit of Internet c...

A free and open source library of simple programming utilities (written in C), including linked lists, AVL and Splay balanced binary trees, a simple caching system, Sparse Arrays. [Open source, LGPL]

Cross-platform compression libraries. [Open source, Commercial]

Source-file library derived from the many fine software packages written by D.J. Bernstein; collects files from various packages into a central repository from which code is easy to use in new programs.

C programming library providing a virtual i386 running in protected mode.

A C programming library for creating cross platform user interfaces across Unix, Linux, Posix, VMS, DOS and Windows.