zlib

ZLIB(3)                    Library Functions Manual                    ZLIB(3)

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 con-
       sume 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  li-
       brary 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  ac-
       companies the source.

       zlib is built in to many languages and operating systems, including but
       not limited to Java, Python, .NET, PHP, Perl, Ruby, Swift, and Go.

       An experimental package to read and write files  in  the  .zip  format,
       written on top of zlib by Gilles Vollant (info@winimage.com), is avail-
       able 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:

              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 AND LICENSE
       Version 1.2.11

       Copyright (C) 1995-2017 Jean-loup Gailly and Mark Adler

       This  software is provided 'as-is', without any express or implied war-
       ranty.  In no event will the authors be held  liable  for  any  damages
       arising from the use of this software.

       Permission  is  granted to anyone to use this software for any purpose,
       including commercial applications, and to alter it and redistribute  it
       freely, subject to the following restrictions:

       1. The origin of this software must not be misrepresented; you must not
          claim that you wrote the original software. If you use this software
          in  a  product, an acknowledgment in the product documentation would
          be appreciated but is not required.

       2. Altered source versions must be plainly marked as such, and must not
          be misrepresented as being the original software.

       3. This  notice may not be removed or altered from any source distribu-
          tion.

       Jean-loup Gailly        Mark Adler
       jloup@gzip.org          madler@alumni.caltech.edu

       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).

                                  15 Jan 2017                          ZLIB(3)