stuff in new window disappears

[mcdougal@cs.uchicago.edu (Tom McDougal)]

This is probably a FAQ; seems to me I knew the answer to this once.  

I create a window and immediately draw to it, but my drawing disappears a
split-second later.  Why?  How do I fix this?  My current hack is (sleep 1)
before drawing.  

I seem to recall something *like* (FORCE-blah <window>) is needed, but I
can't remember what it is and I couldn't find anything in the manual.

Thanks.

-Tom