lib4d_sql is a C library that provides the required functions (connect, prepare, execute, etc.) for writing an SQL client for 4D databases. It uses the public 4D SQL protocol, which is supported by 4D products since version 11. It is already used by the PDO_4D Open Source project, and it might be used to provide others drivers for JDBC, ADO, or ActiveRecord.
The libcommon project is an API implementation in order to respond to general development needs for softwares written in C. This library gives to the developer some utility functions like advanced getopt management, an extra strings treatments function, debugging and tracing functions, and macros for generic lists support. Its goal is to avoid constant re-implementation of the same things for each new program. The libcommon API has been implemented in order to be multi-platform (compatible with i386, ia64, PPC, MIPS, and MIPS 64), hardened (high-level compilation restrictions and implementation requirements), and as few libc dependencies as possible.
libosl, the object storage layer, is a library for storing small to medium-sized data in relational tables. It is easy to use, lightweight, fast, and portable. libosl is suitable for applications that need only a small fraction of the features a full database management system provides.
Drumstick is a C++ wrapper around the ALSA library sequencer interface using Qt4 objects, idioms, and style. The ALSA sequencer provides software support for MIDI technology on Linux. Complementary multiplatform classes for SMF and WRK file processing are also included. This library is used in KMetronome, KMidimon, and KMid2 and was formerly known as "aseqmm".
PolarSSL is a light-weight cryptographic and SSL/TLS library written in C. PolarSSL makes it easy for developers to include cryptographic and SSL/TLS capabilities in their (embedded) applications with as little hassle as possible. Loose coupling of the components inside the library means that it is easy to separate the parts that are needed, without needing to include the total library. PolarSSL is written with embedded systems in mind and has been ported on a number of architectures, including ARM, PowerPC, MIPS, and Motorola 68000. The source is written to have very loose coupling, enabling easy integration of parts in other software projects. Very loosely coupled cryptographic algorithms for MD2, MD4, MD5, SHA1, SHA-256, SHA-512, AES, Camellia, DES, Triple DES, ARC3, and RSA are included.
librouteros is a library that can be used to communicate with devices running RouterOS, a Linux-based operating system by MikroTik. A generic and low-level interface is provided to issue arbitrary commands to the device and receive replies. For some commands, high-level abstractions are provided to simplify communication. The library is thread-safe and reentrant-safe.
Syncless is an experimental, lightweight, non-blocking (asynchronous) client and server socket network communication library implemented in Stackless Python 2.6. It contains an asynchronous DNS resolver (using dnspython) and an HTTP server capable of serving WSGI applications. It aims to be a coroutine-based alternative of event-driven networking engines (such as Twisted and FriendFeed's Tornado). It is already about that fast, but it has fewer features and is less stable now.