Zlib

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zlib
Latest release:	1.2.3 / 2005-07-18
OS:	cross platform
Use:	data compression library
License:	License of zlib/libpng
Website:	http://www.zlib.net/

zlib is an open-source, cross-platform data compression library by Jean-loup Gailly and Mark Adler and is an abstraction of the DEFLATE compression algorithm used in their gzip file compression program. The first public version, 0.9, was released on May 1, 1995 and was originally intended for use with libpng image library. zlib is distributed under the zlib license.

[edit] Software using zlib

Today, zlib is something of a de facto standard, to the point that zlib and DEFLATE are often used interchangeably in standards documents. Hundreds of applications for Unix-like operating systems (such as Linux) rely on it for compression and it is increasingly used on other platforms, such as Microsoft Windows and the Palm OS. A few notable applications are:

• The Linux kernel, where it is used to implement compressed network protocols, compressed file systems and to decompress the kernel image itself at boot time.
• libpng, the reference implementation for the PNG image format, which specifies DEFLATE as the stream compression for its bitmap data.
• The Apache HTTP server, which uses zlib to implement HTTP/1.1 compression.
• The OpenSSH client and server, which rely on zlib to perform the optional compression offered by the SSH protocol.
• The GnuTLS security library, which can optionally use zlib to compress TLS connections.

zlib is also used in many embedded devices because the code is portable and because the library has a relatively small memory footprint.

[edit] See also

• DEFLATE
• gzip
• ZIP (file format)

[edit] External links

• zlib homepage
• List of Zlib related resources