This is the popt command line option parsing library. While it is similiar
to getopt(3), it contains a number of enhancements, including:

        1) popt is fully reentrant
        2) popt can parse arbitrary argv[] style arrays while
           getopt(2) makes this quite difficult
        3) popt allows users to alias command line arguments
        4) popt provides convience functions for parsing strings
           into argv[] style arrays

WWW: http://freshmeat.net/projects/popt/