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 mmaped), 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 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 example.c and minigzip.c.
Changes to this version are documented in the file ChangeLog that accompanies the source, and are concerned primarily with bug fixes and portability enhancements.
A Java implementation of zlib is available in the Java Development Kit 1.1: