This module provides a way to obtain filesystem disk space information. 
This is a Unix only distribution. If you want to gather this information 
for Unix and Windows, use Filesys::DfPortable. The only major benefit of 
using Filesys::Df over Filesys::DfPortable, is that Filesys::Df supports 
the use of open filehandles as arguments.

The module should work with all flavors of Unix, including Mac OS X 
(Darwin, Tiger, etc), and Cygwin.

WWW: http://search.cpan.org/dist/Filesys-Df/