[PyKDE] deadlock with QThread
lists at gregfortune.com
Sun Aug 25 09:42:00 BST 2002
We've managed to create a very nasty deadlock using the QThread class in an
application we are developing. I've attached some sample python code that
demonstrates several cases in which QThread does work and one case in which
it does not.
Our application's code is closest to test case 4, but our code still does not
work. Regardless, test case 2 needs addressed and probably fixed :) It is
also possible that we just aren't using the QThread stuff correctly and in
that case, I'd love to know what we've missed.
btw, the deadlock occurs when trying to import any module inside the
QThread.run call. Any function level imports in any code called by
QThread.run lock up the thread and any imports directly in the QThread.run
call lock up the thread.
Oddly enough, imp.load_module() allows us to get around the bug, but only for
standard python modules (perhaps because they are loaded as an .so??). 3rd
party modules fail even in an imp.load_module() even though imp.find_module
is successful. Also, removing any function level imports also fixes the
problems, but the imports that cause problems are not in our code. They are
actually in the MySQLdb module, but any module doing a function level import
will cause the lock...
I'm still trying to determine what makes our code different from test case 4,
which runs. If I figure that out, I'll send another test case that does not
work... Until then, let me know what you find out with regards to test case
To execute test case 2, just run
Thanks for any help,
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