ZLIB(3)                                                   ZLIB(3)

       zlib - compression/decompression library

       [see zlib.h for full description]

       The  zlib  library  is  a general purpose data compression
       library.  The code is thread safe.  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 will be added  later  and
       will have the same stream interface.

       Compression  can  be  done in a single step if the buffers
       are  large  enough  (for  example  if  an  input  file  is
       mmap'ed), or can be done by repeated calls of the compres-
       sion 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  (.gz)  format  with  an interface similar to that of

       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 case  of  corrupted

       All functions of the compression library are documented in
       the file zlib.h.  The distribution source  includes  exam-
       ples  of  use  of  the  library  the  files  example.c and

       A Java implementation of zlib is  available  in  the  Java
       Development Kit 1.1


       A Perl interface to zlib, written by Paul Marquess  (pmar-
       quess@bfsec.bt.co.uk)  is available at CPAN (Comprehensive
       Perl Archive Network) sites, such as:


       A  Python  interface  to  zlib  written  by  A.M. Kuchling
       <amk@magnet.com> is available  from  the  Python  Software
       Association sites, such as:


       Questions about zlib should be sent to:

              zlib@quest.jpl.nasa.gov or, if this fails,  to  the
              author  addresses  given below.  The zlib home page


       The data format used by the zlib library is  described  by
       RFC (Request for Comments) 1950 to 1952 in the files:

              ftp://ds.internic.net/rfc/rfc1950.txt (zlib format)
              rfc1951.txt (deflate format)
              rfc1952.txt (gzip format)

       These documents are also available in other formats from:


       Version  1.1.3  Copyright  (C)  1995-1998 Jean-loup Gailly
       (jloup@gzip.org)  and   Mark   Adler   (madler@alumni.cal-

       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 soft-
       ware.  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  sug-
       gested  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).

                           9 July 1998                          1