Path: utzoo!attcan!uunet!tut.cis.ohio-state.edu!ucbvax!ECN.PURDUE.EDU!tongz
From: tongz@ECN.PURDUE.EDU (Tong Zheng)
Newsgroups: comp.windows.x
Subject: Can an application know a DESTROY/KILL is applied on itself?
Message-ID: <9101140734.AA16046@mn.ecn.purdue.edu>
Date: 14 Jan 91 07:34:26 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Lines: 41

Hi,

The subject line may look a little confusing, I will give 
detail in following.

I am running X11R4,  and using Xlib&Xt in twm/mwm/olwm.

By far I understand, to destroy a window in a WM, 
such as using "destroy/kill" in twm, "close" in mwm,
is to tell X server to close the connection with the application
which creates the window.

My question is, is there any way an application can be notified
or get to know a DESTROY/KILL instruction is applied to the
application.  The purpose to do that is for safty.  For example,
a drawing program certainly wants to save the contents before
terminated by an acciendly DESTROY/KILL from the WM.

The DestroyNotify in Xlib doesn't work because the X serevr  
will first close the connection with application, how do you
expect the application can get any event after the connection
is closed.  I tried the destroyCallback in Xt(using Athena Widget Set), 
but my codes in the callback function didn't get processed at all.

Well, I don't know whether my understanding above is right or not.
I would like to hear opinions from you Xperts.  Any comment or 
suggestion is appreciated.

You may post on the net or reply via e-mail.  If there are enough 
interests, I will post the summary on the net.


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