>Inside the Posix shell, are the commands the same as HP-UX?

Similar, but not exactly the same. Not all Unixen are created equal ;-)

>All suggestions greatly appreciated.

I seem to recall a "Unix for MPE" Users paper/presentation by
Neil Armstrong that might be useful for getting an introduction.

 see http://www.robelle.com/library/tutorials/

I also noticed a Posix related paper by Steve Hoogheem on Jazz;
it deals with Posix programming, so is probably not for the Shell,
but more for the Posix libraries (compared to Intrinsics).

 http://jazz.external.hp.com/papers/

Maybe the Interex web site has some papers from HP World or
IPROF or Solution Symposium presentations. Just a thought.

Lars.