ZLIB(3) ZLIB(3)
28 Apr 2013
NAME
zlib - compression/decompression library
SYNOPSIS
[see zlib.h for full description]
DESCRIPTION
The zlib library is a general purpose data compression library. The
code is thread safe, assuming that the standard library functions used
are thread safe, such as memory allocation routines. It provides in-
memory compression and decompression functions, including integrity
checks of the uncompressed data. This version of the library supports
only one compression method (deflation) but other algorithms may be
added later with the same stream interface. Compression can be done
in a single step if the buffers are large enough or can be done by
repeated calls of the compression function. In the latter case, the
application must provide more input and/or consume the output
(providing more output space) before each call. The library also
supports reading and writing files in gzip(1) (.gz) format with an
interface similar to that of stdio. The library does not install any
signal handler. The decoder checks the consistency of the compressed
data, so the library should never crash even in the case of corrupted
input. All functions of the compression library are documented in the
file zlib.h. The distribution source includes examples of use of the
library in the files test/example.c and test/minigzip.c, as well as
other examples in the examples/ directory. Changes to this version
are documented in the file ChangeLog that accompanies the source.
zlib is available in Java using the java.util.zip package:
http://java.sun.com/developer/technicalArticles/Programming/compression/
A Perl interface to zlib, written by Paul Marquess
(pmqs@cpan.org), is available at CPAN (Comprehensive Perl Archive
Network) sites, including:
http://search.cpan.org/~pmqs/IO-Compress-Zlib/ A Python interface
to zlib, written by A.M. Kuchling (amk@magnet.com), is available
in Python 1.5 and later versions:
http://docs.python.org/library/zlib.html zlib is built into tcl:
http://wiki.tcl.tk/4610 An experimental package to read and write
files in .zip format, written on top of zlib by Gilles Vollant
(info@winimage.com), is available at:
http://www.winimage.com/zLibDll/minizip.html and also in the
contrib/minizip directory of the main zlib source distribution.
SEE ALSO
The zlib web site can be found at:
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ZLIB(3) ZLIB(3)
28 Apr 2013
http://zlib.net/ The data format used by the zlib library is
described by RFC (Request for Comments) 1950 to 1952 in the
files:
http://tools.ietf.org/html/rfc1950 (for the zlib header and
trailer format)
http://tools.ietf.org/html/rfc1951 (for the deflate compressed
data format)
http://tools.ietf.org/html/rfc1952 (for the gzip header and
trailer format) Mark Nelson wrote an article about zlib for the
Jan. 1997 issue of Dr. Dobb's Journal; a copy of the article is
available at:
http://marknelson.us/1997/01/01/zlib-engine/
REPORTING PROBLEMS
Before reporting a problem, please check the zlib web site to verify
that you have the latest version of zlib; otherwise, obtain the latest
version and see if the problem still exists. Please read the zlib FAQ
at:
http://zlib.net/zlib_faq.html before asking for help. Send
questions and/or comments to zlib@gzip.org, or (for the Windows
DLL version) to Gilles Vollant (info@winimage.com).
AUTHORS
Version 1.2.8 Copyright (C) 1995-2013 Jean-loup Gailly
(jloup@gzip.org) and Mark Adler (madler@alumni.caltech.edu). This
software is provided "as-is," without any express or implied warranty.
In no event will the authors be held liable for any damages arising
from the use of this software. See the distribution directory with
respect to requirements governing redistribution. The deflate format
used by zlib was defined by Phil Katz. The deflate and zlib
specifications were written by L. Peter Deutsch. Thanks to all the
people who reported problems and suggested various improvements in
zlib; who are too numerous to cite here. UNIX manual page by R. P. C.
Rodgers, U.S. National Library of Medicine (rodgers@nlm.nih.gov).
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