Info-ZIP's UnZip 6.0: generic C sources
  Complete C source code for Info-ZIP's
  PKUNZIP-compatible .zip extractor, for
  all supported compilers and platforms
  (Unix, OS/2, MS-DOS, NT, VMS, Amiga,
  Atari, Mac, Acorn, VM/CMS, etc.), plus
  lots of pretty decent documentation.
This is FREE (but copyrighted) software.
See LICENSE for details on distribution
and reuse.