zlib 1.2.11 is a general purpose data compression library. All the code is
thread safe. The data format used by the zlib library is described by RFCs
(Request for Comments) 1950 to 1952 in the files
http://tools.ietf.org/html/rfc1950 (zlib format), rfc1951 (deflate format) and
rfc1952 (gzip format).
Download zlib 1.2.11 Windows archives here below.
Windows binary packages for zlib are available for Visual Studio 2013, 2015 and 2017 ABIs, 32bit and 64bit, for MinGW 5.3.0 32 bit and MinGW 7.3.0 64 bit.