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From: clive@ixi.UUCP (Clive Feather)
Newsgroups: comp.windows.x
Subject: Re: Save under problem
Message-ID: <171@ixi.UUCP>
Date: 19 May 89 20:20:57 GMT
References: <3018@ncsuvx.ncsu.edu>
Reply-To: clive@ixi.uucp (Clive Feather)
Organization: IXI Limited
Lines: 31
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In article <3018@ncsuvx.ncsu.edu> rcb@cccvs1.ncsu.edu (Randy Buckland) writes:
>I am having a problem using save-under attribute that and wondered if anyone
>had seen this.
>
>I have a main window with a drawing in it. I have a child of this window
>that is unmapped that will overlay part of the drawing and has the
>attributes save-under set to true [...]
>everything works ok except that save-under is not being used. I get an expose
>event for the main window every time I unmap the child. Now you might
>be thinking that save under is not implemented on my workstation, but it is.
>[...]
>I know the save-under works since I can make it start working in my window
>in only one way as follows [...]

Remember that the server is entitled to do what it likes about save-unders
and backing-store; it can always implement them, never implement them, or
switch them on and off every 30 seconds ! The flags in the window attributes
are hints to the server, not commands; when a window is obscured, the server
has the choice of saving the contents or generating an expose when it becomes
visible again.

All this means that you must live with the behaviour you are seeing; the
server is behaving correctly.

Of course, if you are asking *why* your server is behaving this way, then
that's a different and legitimate question (to which I don't know the answer),
provided that you accept that you might not be able to change it.
-- 
Clive D.W. Feather           clive@ixi.uucp
IXI Limited                  ...!mcvax!ukc!ixi!clive (riskier)
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