Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!cs.utexas.edu!usc!ucsd!ucbvax!bloom-beacon!ATHENA.MIT.EDU!swick
From: swick@ATHENA.MIT.EDU (Ralph R. Swick)
Newsgroups: comp.windows.x
Subject: Re: XtAppMainLoop - are there alternatives?
Message-ID: <8912121813.AA12898@LYRE.MIT.EDU>
Date: 12 Dec 89 18:13:43 GMT
References: <1038@hedora.cs.utexas.edu>
Sender: root@athena.mit.edu (Wizard A. Root)
Organization: DEC/MIT Project Athena
Lines: 21


    Date: 12 Dec 89 16:57:51 GMT
    From: snorkelwacker!usc!cs.utexas.edu!mbarnett@BLOOM-BEACON.MIT.EDU
 (Michael Barnett)

    void quit()
    {
      XtDestroyApplicationContext(app_context);
      NOT_DONE = 0;
    }

    the application works fine, KCL allows me to define a function
    main-loop that does nothing but call main_loop in the C code.
    but when i try to call quit (from a callback), i get a 
    segmentation violation (which occurs in the function main_loop,
    after the while loop).

Don't destroy the application context from within XtDispatchEvent
(i.e. from within a callback).  This destroys lots of state that
Xt needs.  If you simply set your flag and do the destroy when
XtDispatchEvent returns, you'll be safe.