Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!wuarchive!decwrl!asente
From: asente@decwrl.dec.com (Paul Asente)
Newsgroups: comp.windows.x
Subject: Re: Processing toolkit events
Message-ID: <2759@bacchus.dec.com>
Date: 15 Feb 90 00:11:10 GMT
References: <3947@hub.UUCP>
Distribution: comp
Organization: DEC Western Software Lab
Lines: 26

In article <3947@hub.UUCP> tom@bears.ucsb.edu writes:
>I'm trying to process events using the X toolkit in a way that will not
>block when the queue is empty.  This is what I'm doing:
>
>  XEvent event;
>
>  while (XtAppPending(context)) {
>    XtAppNextEvent(context, &event);
>    XtDispatchEvent(&event);
>  }
>
>However, this seems to block when there are no events in the queue.  Am
>I doing something wrong, or is this a bug?

Are you using timers or alternate input sources?  XtAppPending returns
non-zero when these exist but XtAppNextEvent still blocks if there are no
X events.  If this is the case, you might try

    while (XtAppPending(context) & XtIMXEvent) {
	...

The Intrinsics will add timers themselves if you or the widgets use the
selection mechanism.  The widgets may be adding timers themselves.

	-paul asente
	    asente@decwrl.dec.com	decwrl!asente