Re: Tcl crashes

From: Bruce Hartweg (bruce-news_at_hartweg.us)
Date: 06/28/04 

Date: Mon, 28 Jun 2004 14:49:19 -0500

Joseph Kaufman wrote:
> I have an [incr]Tcl GUI application, S. Typing S at the prompt brings
> up GUI A at the terminal IP. Later on, at some point due to a certain
> outside event, S launches GUI B, as a toplevel widget, to a remote IP.
> This means, S manages 2 GUIs, GUI A at the terminal IP, and GUI B at a
> remote IP. It happens at times, not always, that GUI A crashes, and
> with it the entire application S crashes. My suspicion is, the remote
> IP where GUI B is goes out of existence, brings down GUI B, and this
> in turn brings down GUI A. I have no way of checking GUI B since it is
> at a remote site.
>
> This same application, a) when there is no GUI B, or b) GUI B is
> launched at the terminal IP where GUI A is, has never crashed.
>
> My first design was, GUI B was a separate TCL script and S
> communicated with it through a socket. Then, also GUI A never crashed.
> The problem started when I made GUI B a part of S as an [incr]Tcl
> class. This bolsters my suspicion that GUI B is the culprit.
>
> Your help is greatly appreciated.

are there any logs/messages at the terminal where the program
is launched from? Losing connection to an X display is indeed a
fatal condition, and if that is the case you may well see an X
protocol level diagnostic message on your terminal. (lost
conection to Server blah blah blah). From your description
this seems the most plausible answer to me.

If this is the case then there isn't much you can do about it
in the code, other than reverting your design to the point where
the external GUI is also an external process.

Bruce