[nhc-bugs] How to make System Calls in NHC98?

Hi :) , I am creating a tiny app in Haskell to search for a directory in the tree and change the current shell directory just to learn to program better in Haskell and I've always used the Win/Hugs98 interpreter but I've just moved to FreeBSD/NHC98 because I want binary code and the thing is I can't find a function in NHC98 to make a pipe to comunicate with the shell (csh in my case) and that's the question: are the FreeBSD pipes functionality available in NHC98? By the way, can one make arbitrary System Calls in NHC98 by any means? if no, how can I change the shell's current directory? Regards, Alberto Dominguez (Spain)