Path: utzoo!attcan!uunet!lll-winken!ames!hc!pprg.unm.edu!unmvax!tut.cis.ohio-state.edu!bloom-beacon!dinorah.mit.EDU!art
From: art@dinorah.mit.EDU (Arthur B. Smith)
Newsgroups: comp.windows.x
Subject: Univeral invalid XID
Message-ID: <8902091457.AA25539@dinorah.wustl.edu>
Date: 9 Feb 89 14:57:45 GMT
Sender: daemon@bloom-beacon.MIT.EDU
Organization: The Internet
Lines: 14

Hello!

Is there any value that is never a valid XID?  I would like to know if a 
window has been defined just by checking the value of the window, not 
carrying around another flag.  In X.h "None" is #define'd to 0L with the
comment "universal null resource or null atom".  Does that mean I can
do something like

if (win == None)
	win = XCreateSimpleWindow(...);

?  TIA.

	art smith (art@dinorah.wustl.edu)