Path: utzoo!attcan!uunet!cs.utexas.edu!tut.cis.ohio-state.edu!bloom-beacon!EXPO.LCS.MIT.EDU!rws
From: rws@EXPO.LCS.MIT.EDU
Newsgroups: comp.windows.x
Subject: Re: save-under bug?
Message-ID: <8905162010.AA19365@expire.lcs.mit.edu>
Date: 16 May 89 20:10:13 GMT
References: <8116@boring.cwi.nl>
Sender: daemon@bloom-beacon.MIT.EDU
Organization: The Internet
Lines: 32


    This makes me think that the save-under code somehow saves the
    entire window (even that part which is invisible!), rather than only the
    part below the menu.

It isn't directly saving the entire window, but I suspect your application is
repainting the entire window (and the server is saving the repaint).  In the
sample server, save-unders are implemented in the "device independent" layer as
a fallback option in case the device dependent layer doesn't provide them (of
course, none of the ddx layers provide real save-unders.  In this fallback,
backing store is enabled on the windows-to-be-obscured.  This causes Exposure
events to be generated for all obscured (including off-screen) portions of
the window.  In your case, that's a lot of real estate.  Unless your
application is very clever, it is responding to these exposures.  If you run
your program under a debugger, or under xscope, you should be able to verify
this.

	- a server bug?

It isn't a "bug" exactly, but it is a misfeature.

	- required by the protocol?

Definitely not.

	- a figment of my imagination?

Dunno, how long have you been up?

	- fixed in R4?

It's not on our hit list, although it is on our wish list.