Re: more general: strategy against errors with gtk + threads

[Paul Pogonyshev <pogonyshev gmx net>]

Felix Kater wrote:
> in my last program I use threads more extensivly than before. From time
> to time it crashes with gtk errors. Now I wonder if my strategy of
> avoiding gtk errors in a multi threaded environment is suitable:
>
> Up to now I tried to narrow all changes to gtk widgets (renaming labels,
> draw into drawables etc.) to one single function, which is running in
> idle time. It checks "change-booleans" for each widget and reacts on
> that (renames labels etc.).
>
> Is this the right way to do?

While I think it is possible to fix your program to work without errors,
this is not something I would call "the right way."  I suggest you use
asynchronous queue to send message to GUI master thread requesting some
work.  You can find implementation somewhere in this list's archive.

> And what is actually - in general - causing the errors?

A few possibilities that come to mind:

* You must set the "work-required" flag only after setting up all required
  information (i.e. new label text.)

* You must not start setting up work information until "work-required" flag
  is reset.  (And you can easily waste CPU time on this...)

* You must reset the "work-required" flag in the master thread only after
  the job is completed fully.

Paul