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Subject: Re: [Boost-users] [threads] Deadlock?
From: The Novice Coder (boost_at_[hidden])
Date: 2011-04-04 16:48:10

 On Mon, 04 Apr 2011 13:08:51 +0200, Jan Kundrát wrote:
> First of all, I wonder what your reason is to go with boost's
> threading
> over Qt's facilities, given that your application is already tightly
> bound into using Qt (you're using their event loop and events).

 Well, disclaimer on that - Wasn't my idea. My task is to get it to
 work. But basically, there's the GUI section of code, and the work
 section of code and the two have very little to do with each other, as
 there's 3 different GUI tool kits that are used depending on the
 project. The "configurator" (which runs in the background) calls the
 toolkit with a list of windows that need to be created.

> Are you sure that the Qt's event loop is running? Are both threads
> executing their own event loop? (You should check this one, it
> depends
> on you if you want each thread to run an event loop, or do something
> else. In any case, make sure you understand the semantics of
> QCoreApplication::postEvent and how these events are delivered).

 Hmmm. That's definitely something I need to look into. It seems to be
 deadlocking on the mutex's, but it might be stopping there. The code
 reportedly works fine in Linux, Mac, and XP, but chokes on Win 7. (I'm
 the short-straw dev who's forced to use 7.) I'll read up here next.

> Finally, you code is missing some context to understand what you're
> trying to achieve. I have no idea what the "qtService" stands for,
> not
> what "s" is, if there are any classes derived from the QObject, how
> you
> intend to use the events, etc etc.

 From what I understand, the basic gist is that a piece of code, like
 the GUI creation, MUST run from the main thread, and this code takes
 care of that, switching the context to the main thread (Or whatever
 thread is requested).
 As for what qtService means, I haven't the foggiest. It's definitely
 NOT descriptive enough for my tastes, as it seems to be one step away
 from qtGoDoSomething.

> Cheers,
> Jan

 Thanks for the feedback! =)
 Time to hit the manuals again. (Probably both figuratively and

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