PW32 is an implementation of the (subset of) POSIX/Unix API for Win32 systems. Its main concerns are efficiency and full platform coverage, including adequate support for low-end Win9x systems. PW32 is based on DJGPP's runtime library by DJ Delorie. PW32 is licensed under LGPL.
Also, PW32 is a collection of software ported with PW32 library. The aim is to have comprehensive GNU/Win32 distribution, easily installable, and correctly and efficiently working.