Re: Need help debugging Gdk-ERROR

["J. Ali Harlow" <gtk-list avrc city ac uk>]

On Fri, 16 Mar 2001, Eric M. Monsler wrote:
> "J. Ali Harlow" wrote:
> > 
> (snip)
> > See Havoc's recent message:
> 
> I tried this, actually, and should have mentioned it.
> 
> But, after the Gdk-ERROR (there were actually two this time, same codes,
> serial's differing by 1), there was the report that the application has
> exited with return value 1.  I tried backtrace anyway, but was told 'no
> stack'.

My apologies. It appears that gdk_x_error() uses fprintf if G_ENABLE_DEBUG
is not defined. You should be able to just set a breakpoint on gdx_x_error in
gdb before you run the program and then backtrace when it gets triggered.

> One reason I didn't mention that I had tried this was that I was not
> sure that the --g-fatal-warnings approach was useful for tracking down X
> errors.

Obviously not. Learn something new every day...

> If I run without the --sync argument, my understanding is that when the
> error occurs, the current state of the stack may not represent the calls
> that produced the error.  Is this correct?

Yes. With --sync, each X call will wait for a response back from the server
before returning to the application. Without --sync, the error may not be
noticed until a number of X requests have been sent after the one that actually
caused the error.

-- 
Ali Harlow                              Email: ali avrc city ac uk
Research programmer                     Tel:   (020) 7477 8000 X 4348
Applied Vision Research Centre          Intl: +44 20 7477 8000 X 4348
City University                         Fax:   (020) 7505 5515
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