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From: David_Alan_Lee@cup.portal.com
Newsgroups: comp.windows.x
Subject: Recovery from fatal IO errors
Message-ID: <42939@cup.portal.com>
Date: 4 Jun 91 04:30:55 GMT
Organization: The Portal System (TM)
Lines: 26

I have a program that needs to communicate with several displays.
The problem is that if one of the displays crashes, say an X 
terminal that a user turns off, then I get a Fatal IO error.
If I use XSetIOErrorHandler() I can trap this error, but no matter
what I do, I cant recover from it.  

I do not want my program crashing just because one of the displays
goes down.  I have tried everything I can think of to handle this,
including doing an XCloseDisplay() from within the error handler.
If I return from the routine, it gets call again, over and over.
I am able to avoid this by doing a longjump() out of the routine,
but if I try to close the display my error handler gets called.
If I reset the handler to the default my program exits.
If I dont close the display, X cant free up my local resources,
so eventially I will run out of virtual memory  -- because I will
have to open another display later. 

The only solution I have found is forking a child to handle each display.
This does work, but I would prefer to have only 1 process.
Does anyone know of another solution ?

Please Email a copy of any responses.
Thank you
--
Dave Lee
David_Alan_Lee@cup.portal.com