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From: klee@wsl.dec.com (Ken Lee)
Newsgroups: comp.windows.x
Subject: Re: Checking for valid Window ID
Message-ID: <3031@bacchus.dec.com>
Date: 15 Mar 90 20:45:17 GMT
References: <24321@uhnix1.uh.edu>
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Organization: DEC Western Software Laboratory
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In article <24321@uhnix1.uh.edu>, atmaram@csun11.cs.uh.edu (S. Atmaram) writes:
> My program has the Window ID of a window on a remote display. I
> wish to check whether or not the ID is valid (that is, whether the
> window still exists), before doing an XSendEvent.

You should send the event without checking.  Install an error handler
to catch any BadWindow errors indicating that the window no longer
exists.  Since X is shared and asynchronous, there is no guarantee that
a window that existed when you did your check will still exist when you
send the event.

Ken Lee
DEC Western Software Laboratory, Palo Alto, Calif.
Internet: klee@wsl.dec.com
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