Re: [java-gnome-hackers] Xlib: unexpected async reply

[Andrew C. <an...@op...>]

On Fri, 2008-06-13 at 22:13 +0200, Stefan Prelle wrote:
> I have a fairly complex java-gnome application which produces the
> following exception after some time:
>   Xlib: unexpected async reply (sequence 0x316e)!

I haven't seen one of those in ages.

We go to *considerable* effort to lock GDK properly and to thereby make
java-gnome transparently thread safe. See
http://research.operationaldynamics.com/blogs/andrew/software/gnome-desktop/gtk-thread-awareness.html
and
http://research.operationaldynamics.com/blogs/andrew/software/java-gnome/thread-safety-for-java.html

It is possible that we missed synchronizing in some piece of Override
code, though I tend to be careful about looking for such things.

There was previously a separate problem where a native thread not
spawned by Java would not be attached, but that was fixed in revno 486.
Vreixo pointed out that we'll also need to synchronize access to the
knownProxies collections at some point, but that probably is not your
problem either.

Another possibility is that you've hit some part of GTK that is not
properly coded to be thread aware. That would be a bug, but finding it
may prove tricky. [FileChooser was rife with them at once point, but my
understanding is that most of that was cleaned up]

... if you grep the GTK source files you're code is going through for
add_timeout or add_idle and don't see it as gdk_threads_add_timeout() or
gdk_threads_add_idle() then that's probably a concern.


> I did not add Java threads to my application, so all I did was relying
> on the threads provided by the underlying GTK+ library.

That does tend to point to the sort of problem that GtkFileChooser
[once] caused.

AfC
Sydney

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Andrew Frederick Cowie

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