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From: etaylor@wilkins.iaims.bcm.tmc.edu (Eric Taylor)
Newsgroups: comp.windows.x
Subject: Re: How Do You Monitor Events For More Than 1 Display?
Message-ID: <3014@gazette.bcm.tmc.edu>
Date: 3 Dec 90 16:24:36 GMT
References: <9401@pasteur.Berkeley.EDU>
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Reply-To: etaylor@wilkins.iaims.bcm.tmc.edu (Eric Taylor)
Organization: Baylor College of Medicine, Houston, Tx
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With mulitple displays, you have to use select.
If you are not familiar with it, refer to UNIX documentation.
Essentially, use select on all of the file descriptors of the
displays you have open.  When data is avaliable on one of them,
do your XNextEvent on it.

Be careful to make sure that XPending is 0 on all displays before
calling select.

for ever
	busy = False ;
	for each display dpy
		if XPending(dpy) > 0
			XNextEvent(dpy,&event)
			Process event
			busy = True
		end if
	end for
	if not busy
		Construct fdset of all displays
		select(...,&fdset,...)
		for each display dpy that had activity
			XNextEvent(dpy,&event)
			Process event
		end for
	end if
end for
--
					Eric Taylor
					Baylor College of Medicine
					etaylor@wilkins.bcm.tmc.edu
					(713) 798-3776