Path: utzoo!attcan!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!snorkelwacker.mit.edu!bloom-beacon!LARRY.MCRCIM.MCGILL.EDU!mouse
From: mouse@LARRY.MCRCIM.MCGILL.EDU
Newsgroups: comp.windows.x
Subject: Re:  Access error freeing allocated color cells on static visuals
Message-ID: <9012192015.AA09527@Larry.McRCIM.McGill.EDU>
Date: 19 Dec 90 20:15:32 GMT
Sender: daemon@athena.mit.edu (Mr Background)
Organization: The Internet
Lines: 23

> I have some code that allocates color cells with AllocColor and later
> frees them with FreeColors, and it works fine when the colormap has a
> read/write kind of visual (GrayScale, PseudoColor, DirectColor).
> When the visual is a static one (StaticGray, StaticColor, TrueColor),
> any attempt to FreeColors gets an Access error.

More precisely, you need another condition as well: "and it's the
default visual for the screen".

> Is this a common mistake in X server implementations?

Yes.  Until I tracked it down it was in the MIT server and has
doubtless spread to others, as you note.

> Visual said it was a bug in the server and is corrected the latest
> release.

Good for them (though I'd prefer patches, but you can't have everything).

					der Mouse

			old: mcgill-vision!mouse
			new: mouse@larry.mcrcim.mcgill.edu