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From: veerabad@buster.cps.msu.edu (Vibhu Veerabadrappa)
Newsgroups: comp.windows.x
Subject: How to simulate a blocked i/o in an event driven program?
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Message-ID: <1991Feb23.213455.19457@msuinfo.cl.msu.edu>
Date: 23 Feb 91 21:34:55 GMT
Sender: news@msuinfo.cl.msu.edu
Distribution: usa
Organization: Michigan State University, College of Engineering
Lines: 35


Hi,
	Here is a question on X window programming:

	I have a program in which I pop up a dialog window from which
I expect the user to input some data which I need, later in the program.
But since X window programs are event driven, the program does not "Block"
ubtil the user types in the required data, but goes on. 

		  .
		  .
		  .
            popupwindow ();
	    /* 
	      some processing
	      which requires 
	      the user's data ...
	    */
		  .
		  .
		  .
	I tried to have a loop after the pop up, waiting until the data is
input. But the pop up window was never popped up !!

	Young's book has an example in which the program does not block,
and he also says that it is difficult to simulate "blocked" i/o ... but 
does not say it is impossible !! So there must be a way out.

	Can anyone provide me with a hint how it can be done? 

	Thank you very much.

	My e_mail address is: veerabad@buster.cps.msu.edu

------Vibhu.