[nonameiguess]

Heck, for what it's worth, even Make has this issue, as people quite often write Makefiles assuming you have a bunch of tools installed that may or may not be part of the POSIX specification. I wish I could find it now, but somewhere in the GNU Make guide book is a list of more or less "approved" utilities you're supposed to be able to safely assume are installed on any GNU based system that you can use in a Makefile, and you're not supposed to go beyond that.