How can I foreground an app?

[Victor Eijkhout]

(With my apologies for that case of verbing in the subject :-)

I'm writing an alarm clock. When the alarm goes off it would be nice 
if the app became foremost, so that the user could hit the Any Key to 
snooze the alarm.

So how do I tell an app that's not foremost, or maybe even hidden to 
become foremost?
-- 
Victor Eijkhout <eijkhout at cs.utk.edu>
tel: 865 974 9308 (W), 865 673 6998 (H), 865 974 8296 (F)
http://www.cs.utk.edu/~eijkhout/