Filitering in File Selection Widget

[Raymond Wan <rwan cs mu oz au>]

Hi all,

	I was wondering if it was "easy" to change the file selection
widget so that only certain files appear (that is, files with a particular
extension, for example).  By "easy", I mean if there's a way to do it
without messing with its code...with the way I program, I can make the
problem worse.  :)  Is there a function/etc. that I can use? 

	Thank you in advance!

Ray