posh package in pkgsrc doesn't work with POSIX getopt().
Likely it works with GNU getopt() only.
Note: It can be compiled, but fails horribly at runtime e.g. on NetBSD.

To make this more obvious, I have first enabled the testsuite for "make test".
This package solves the problems by using getopt() from gnulib.

Import of this approach was rejected by wiz@ because it's hard to maintain.
I leave this package in wip for reference.