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From: toml@ninja.Solbourne.COM (Tom LaStrange)
Newsgroups: comp.windows.x
Subject: Re: No expose after map if backing store?
Message-ID: <TOML.91Jan18095908@ninja.Solbourne.COM>
Date: 18 Jan 91 14:59:08 GMT
References: <1658@rrzbu.UUCP> <7320012@hpfcso.HP.COM>
Sender: toml@Solbourne.COM (Tom LaStrange)
Organization: Solbourne Computer, Inc.
Lines: 22
In-Reply-To: stroyan@hpfcso.HP.COM's message of 17 Jan 91 17:08:13 GMT


   >    As anybody knows, before drawing to a window just mapped one has to wait
   >    for an exposure event. Fine.
   >
   >    But why does the program below hang on R4 servers with backing store
   >    and runs fine on servers without?
   >
   >    Do I really have to ask the server if it will maintain backing store
   >    before doing the XNextEvent() or is it a bug in the server?

   I suggest that rather than just asking for ExposureMask you also ask for
   StructureNotifyMask and proceed after a MapNotify event.  Asking for
   ExposureMask is still a good idea since the server may generate
   exposures instead of offering backing store.

Hi Mike,
It's been my experience that if the server provides backing store it may
send you an Expose event even before mapping the window.  Wouldn't waiting
for an Expose event following a MapNotify potentially not work?

--
Tom LaStrange        toml@Solbourne.COM