Free compression library software for linux

LiON Library is a full nonblocking, single thread library with an API that is portable and easy to use.
LiON Library has full network support, files, and pipes (for spawning children, or processes to communicate with). All types can also be rate (KB/s) limited, and full SSL support is included.
Main features:
- Nonblocking Networking.
- Nonblocking File I/O.
- Nonblocking pipe/system and fork commands for spawning helper programs.
- Event driven, event passback for all situations.
- SSL incorporated, with auto-detection.
- Portable (Already confirmed NetBSD, Solaris, Linux, OsX and Win32)
- Single process / thread library.
- Numerous Sample programs included.
- Support both in-library sleep/CPU-release, or in Application.
- Full buffering control, and flow control.
- CPS (KB/s) rate limits on _any_ I/O type. (Socket, File & Pipe)
- Adoptable foreign file-descriptors API.
- Clean API with documentation, although man-page comming.
- Direct, or event driven, failure modes supported.
- Exclusive File I/O locking optional, across all platforms.
- Internal compression optional.
- Very simple to use for line-by-line protocols, or binary chunk data transfers.
- Full UDP support
- Encrypted File IO support (blowfish, dependent on SSL)
- contrib/ sources include Directory listings library for all platforms.
- Python support! Using SWIG there now is an easy way to do async SSL in Python
- Timers! Callback timers in relative or absolute time. One-shot or repeat.
Enhancements:
- SSL connections could stall based on buffer size, so this has been fixed.
- Minor autoconf changes were made.
- Missing Win32 files were added to the dist-gzip file again.

Ssh library was designed to be used by programmers needing a working SSH implementation by the mean of a library. Runs only on x86 linux, bsd and MacOS X.
libssh is a C library to access SSH 2 services from a program. It can remotely execute programs, transfer files, and serve as a secure and transparent tunnel for remote programs. Its Secure FTP implementation can play with remote files easily, without third-party programs others than libcrypto (from OpenSSL).
Main features:
- Full C library functions for manipulating a client-side SSH connection
- Lesser GPL licensing -SSH2 protocol compliant
- Fully configurable sessions
- Support for AES-128,AES-192,AES-256,blowfish, in cbc mode
- Use multiple SSH connections in a same process, at same time
- Use multiple channels in the same connection
- Thread safety when using different sessions at same time
- Basic but correct SFTP implementation (secure file transfer)
- RSA and DSS server public key supported
- Compression support (with zlib)
- Public key (RSA and DSS), password and keyboard-interactive authentication
- A complete documentation about its API
- Runs and tested under amd64, x86, arm, sparc32, ppc under Linux, Bsd, MacosX and Solaris
- A developer listening to you
Enhancements:
- Connection timeout support
- Keyboard-interactive authentication (used by Pam with SSH)
- Server public keys management
- 64 bits cpu support
- Enhanced documentation
- and of course a huge number of bugfixe

Open Computer Vision Library is a collection of algorithms and sample code for various computer vision problems. The library is compatible with IPL (Intel Image Processing Library) and utilizes Intel Integrated Performance Primitives for better performance.

Philosophy

Aid commercial uses of computer vision in human-computer interface, robotics, monitoring, biometrics and security by providing a free and open infrastructure where the distributed efforts of the vision community can be consolidated and performance optimized.

conexus is a generalized C++ I/O library that includes support for BSD sockets, serial/TTY, and packet capture (via pcap).

conexus library utilizes sigc++ for object communication. A companion library, conexusgtk, provides a set of gtkmm widgets.

Redline RPM Library is a pure Java library for manipulating RPM Package Manager packages. Currently the project supports reading and creating packages and has an included Ant task useful for integration with build systems. Support for package signatures will be added in a future release.
Enhancements:
- A patch has been merged that adds a Maven pom file, the directive for documentation files and directories, and user and group name attributes for files.

MS CHM is a library for dealing with Microsoft ITSS/CHM format files. Right now, it is a very simple library, but sufficient for dealing with all of the .chm files Ive come across.
Due to the fairly well-designed indexing built into this particular file format, even a small library is able to gain reasonably good performance indexing into ITSS archives.
Applications which use chmlib:
arCHMage
xCHM
GnoCHM
Language bindings for chmlib:
PyCHM (Python)
Archive::CHM (Perl)
Text::CHM (Perl)
libCHMxx (C++)
Enhancements:
- Stack-allocated buffers have been changed to heap-allocated buffers to avoid stack corruption security problems.
- A security advisory for this issue is forthcoming from iDefense [IDEF2125].

The Torque Network Library project is a robust, secure, and easy-to-use cross-platform C++ networking API designed for high performance simulations and games.
It features a UDP- based connection architecture with DoS prevention functionality, different types of data guarantee, bit stream compression, server object replication and updating, and a simple, highly space efficient RPC mechanism.
It includes a deterministic application journaling replay function for eliminating hard to find networking bugs.
Main features:
- Portable
- Powerful RPC Support
- Lightweight and efficient - not intended to be a replacement for CORBA.
- Extremely easy to use - two simple macro definitions and youre done.
- No complex wrapper classes to work with - write and call your functions as you normally would, and TNL will take care of the rest.
- Robust UDP-based notification protocol
- Supports fixed or adaptive rate data transfer.
- Arbitrary sized packet window.
- Robust connection handshaking.
- Handles packet loss/out of order delivery.
- Networked Objects
- Instantiation of objects by name or ID.
- IDs are assigned to NetGroups, so that only objects relevant to a connection can be references.
- Event Support
- Unguaranteed, guaranteed unordered, or guaranteed ordered event delivery.
- Notification to the event when it has been received or dropped by a client.
- Ghost Support
- Most-recent state information is transmitted to clienst.
- Scoping of objects to only those clients for which they are relevant - this helps prevent cheating or data sniffing and makes dramatically more effective use of available bandwidth.
- Prioritization of state updates by arbitrary criteria, such as relative velocity, team, ownership, etc.
- Extensible Protocol Architecture
- Easy to extend the protocol, for instance, to transmit player move information with every packet, or add voice support.
- See Torque for examples of additional capabilities that could be added to the protocol.

CVS Perl library is a Perl module which is a wrapper around the CVS command with an object-oriented interface.

Installation:

To install this module type the following:

perl Makefile.PL
make
make test
make install