| 1 |
15 |
jlechner |
.TH ZLIB 3 "18 July 2005"
|
| 2 |
|
|
.SH NAME
|
| 3 |
|
|
zlib \- compression/decompression library
|
| 4 |
|
|
.SH SYNOPSIS
|
| 5 |
|
|
[see
|
| 6 |
|
|
.I zlib.h
|
| 7 |
|
|
for full description]
|
| 8 |
|
|
.SH DESCRIPTION
|
| 9 |
|
|
The
|
| 10 |
|
|
.I zlib
|
| 11 |
|
|
library is a general purpose data compression library.
|
| 12 |
|
|
The code is thread safe.
|
| 13 |
|
|
It provides in-memory compression and decompression functions,
|
| 14 |
|
|
including integrity checks of the uncompressed data.
|
| 15 |
|
|
This version of the library supports only one compression method (deflation)
|
| 16 |
|
|
but other algorithms will be added later
|
| 17 |
|
|
and will have the same stream interface.
|
| 18 |
|
|
.LP
|
| 19 |
|
|
Compression can be done in a single step if the buffers are large enough
|
| 20 |
|
|
(for example if an input file is mmap'ed),
|
| 21 |
|
|
or can be done by repeated calls of the compression function.
|
| 22 |
|
|
In the latter case,
|
| 23 |
|
|
the application must provide more input and/or consume the output
|
| 24 |
|
|
(providing more output space) before each call.
|
| 25 |
|
|
.LP
|
| 26 |
|
|
The library also supports reading and writing files in
|
| 27 |
|
|
.IR gzip (1)
|
| 28 |
|
|
(.gz) format
|
| 29 |
|
|
with an interface similar to that of stdio.
|
| 30 |
|
|
.LP
|
| 31 |
|
|
The library does not install any signal handler.
|
| 32 |
|
|
The decoder checks the consistency of the compressed data,
|
| 33 |
|
|
so the library should never crash even in case of corrupted input.
|
| 34 |
|
|
.LP
|
| 35 |
|
|
All functions of the compression library are documented in the file
|
| 36 |
|
|
.IR zlib.h .
|
| 37 |
|
|
The distribution source includes examples of use of the library
|
| 38 |
|
|
in the files
|
| 39 |
|
|
.I example.c
|
| 40 |
|
|
and
|
| 41 |
|
|
.IR minigzip.c .
|
| 42 |
|
|
.LP
|
| 43 |
|
|
Changes to this version are documented in the file
|
| 44 |
|
|
.I ChangeLog
|
| 45 |
|
|
that accompanies the source,
|
| 46 |
|
|
and are concerned primarily with bug fixes and portability enhancements.
|
| 47 |
|
|
.LP
|
| 48 |
|
|
A Java implementation of
|
| 49 |
|
|
.I zlib
|
| 50 |
|
|
is available in the Java Development Kit 1.1:
|
| 51 |
|
|
.IP
|
| 52 |
|
|
http://www.javasoft.com/products/JDK/1.1/docs/api/Package-java.util.zip.html
|
| 53 |
|
|
.LP
|
| 54 |
|
|
A Perl interface to
|
| 55 |
|
|
.IR zlib ,
|
| 56 |
|
|
written by Paul Marquess (pmqs@cpan.org),
|
| 57 |
|
|
is available at CPAN (Comprehensive Perl Archive Network) sites,
|
| 58 |
|
|
including:
|
| 59 |
|
|
.IP
|
| 60 |
|
|
http://www.cpan.org/modules/by-module/Compress/
|
| 61 |
|
|
.LP
|
| 62 |
|
|
A Python interface to
|
| 63 |
|
|
.IR zlib ,
|
| 64 |
|
|
written by A.M. Kuchling (amk@magnet.com),
|
| 65 |
|
|
is available in Python 1.5 and later versions:
|
| 66 |
|
|
.IP
|
| 67 |
|
|
http://www.python.org/doc/lib/module-zlib.html
|
| 68 |
|
|
.LP
|
| 69 |
|
|
A
|
| 70 |
|
|
.I zlib
|
| 71 |
|
|
binding for
|
| 72 |
|
|
.IR tcl (1),
|
| 73 |
|
|
written by Andreas Kupries (a.kupries@westend.com),
|
| 74 |
|
|
is availlable at:
|
| 75 |
|
|
.IP
|
| 76 |
|
|
http://www.westend.com/~kupries/doc/trf/man/man.html
|
| 77 |
|
|
.LP
|
| 78 |
|
|
An experimental package to read and write files in .zip format,
|
| 79 |
|
|
written on top of
|
| 80 |
|
|
.I zlib
|
| 81 |
|
|
by Gilles Vollant (info@winimage.com),
|
| 82 |
|
|
is available at:
|
| 83 |
|
|
.IP
|
| 84 |
|
|
http://www.winimage.com/zLibDll/unzip.html
|
| 85 |
|
|
and also in the
|
| 86 |
|
|
.I contrib/minizip
|
| 87 |
|
|
directory of the main
|
| 88 |
|
|
.I zlib
|
| 89 |
|
|
web site.
|
| 90 |
|
|
.SH "SEE ALSO"
|
| 91 |
|
|
The
|
| 92 |
|
|
.I zlib
|
| 93 |
|
|
web site can be found at either of these locations:
|
| 94 |
|
|
.IP
|
| 95 |
|
|
http://www.zlib.org
|
| 96 |
|
|
.br
|
| 97 |
|
|
http://www.gzip.org/zlib/
|
| 98 |
|
|
.LP
|
| 99 |
|
|
The data format used by the zlib library is described by RFC
|
| 100 |
|
|
(Request for Comments) 1950 to 1952 in the files:
|
| 101 |
|
|
.IP
|
| 102 |
|
|
http://www.ietf.org/rfc/rfc1950.txt (concerning zlib format)
|
| 103 |
|
|
.br
|
| 104 |
|
|
http://www.ietf.org/rfc/rfc1951.txt (concerning deflate format)
|
| 105 |
|
|
.br
|
| 106 |
|
|
http://www.ietf.org/rfc/rfc1952.txt (concerning gzip format)
|
| 107 |
|
|
.LP
|
| 108 |
|
|
These documents are also available in other formats from:
|
| 109 |
|
|
.IP
|
| 110 |
|
|
ftp://ftp.uu.net/graphics/png/documents/zlib/zdoc-index.html
|
| 111 |
|
|
.LP
|
| 112 |
|
|
Mark Nelson (markn@ieee.org) wrote an article about
|
| 113 |
|
|
.I zlib
|
| 114 |
|
|
for the Jan. 1997 issue of Dr. Dobb's Journal;
|
| 115 |
|
|
a copy of the article is available at:
|
| 116 |
|
|
.IP
|
| 117 |
|
|
http://dogma.net/markn/articles/zlibtool/zlibtool.htm
|
| 118 |
|
|
.SH "REPORTING PROBLEMS"
|
| 119 |
|
|
Before reporting a problem,
|
| 120 |
|
|
please check the
|
| 121 |
|
|
.I zlib
|
| 122 |
|
|
web site to verify that you have the latest version of
|
| 123 |
|
|
.IR zlib ;
|
| 124 |
|
|
otherwise,
|
| 125 |
|
|
obtain the latest version and see if the problem still exists.
|
| 126 |
|
|
Please read the
|
| 127 |
|
|
.I zlib
|
| 128 |
|
|
FAQ at:
|
| 129 |
|
|
.IP
|
| 130 |
|
|
http://www.gzip.org/zlib/zlib_faq.html
|
| 131 |
|
|
.LP
|
| 132 |
|
|
before asking for help.
|
| 133 |
|
|
Send questions and/or comments to zlib@gzip.org,
|
| 134 |
|
|
or (for the Windows DLL version) to Gilles Vollant (info@winimage.com).
|
| 135 |
|
|
.SH AUTHORS
|
| 136 |
|
|
Version 1.2.3
|
| 137 |
|
|
Copyright (C) 1995-2005 Jean-loup Gailly (jloup@gzip.org)
|
| 138 |
|
|
and Mark Adler (madler@alumni.caltech.edu).
|
| 139 |
|
|
.LP
|
| 140 |
|
|
This software is provided "as-is,"
|
| 141 |
|
|
without any express or implied warranty.
|
| 142 |
|
|
In no event will the authors be held liable for any damages
|
| 143 |
|
|
arising from the use of this software.
|
| 144 |
|
|
See the distribution directory with respect to requirements
|
| 145 |
|
|
governing redistribution.
|
| 146 |
|
|
The deflate format used by
|
| 147 |
|
|
.I zlib
|
| 148 |
|
|
was defined by Phil Katz.
|
| 149 |
|
|
The deflate and
|
| 150 |
|
|
.I zlib
|
| 151 |
|
|
specifications were written by L. Peter Deutsch.
|
| 152 |
|
|
Thanks to all the people who reported problems and suggested various
|
| 153 |
|
|
improvements in
|
| 154 |
|
|
.IR zlib ;
|
| 155 |
|
|
who are too numerous to cite here.
|
| 156 |
|
|
.LP
|
| 157 |
|
|
UNIX manual page by R. P. C. Rodgers,
|
| 158 |
|
|
U.S. National Library of Medicine (rodgers@nlm.nih.gov).
|
| 159 |
|
|
.\" end of man page
|