Re: Python Threading

From: dustin_at_[hidden]
Date: 2001-06-25 17:45:06

Thank you for your reply. Here is what I want to accomplish:

1. A long running C++ method within the extension module monitors a 
flag, and exits if the flag is true.
2. A seperate python thread sets the flag when the user hits a cancel 
button.

In order to do this, I will have to release the interpreter lock, so 
that the user interface thread can execute. Can I safely set a 
boolean value within the extension module from the user interface 
thread while the main thread executes within the extension module?

Again, thank you for any assistance, and I apologize if this is not 
the proper venue for my question.

--- In boost_at_y..., Ullrich Koethe <u.koethe_at_c...> wrote:
> dustin_at_d... wrote:
> > 
> > Please excuse my relative ignorance. My question is: I've written 
a
> > Python Extension module in C++ using the Boost Python library. If 
I
> > understand correctly, the thread in which my extension module
> > executes will maintain a lock on the Python interpreter while
> > executing within the extension module, preventing other python
> > threads from executing. Can I get around this by releasing the
> > interpreter lock? Any assistance would be greatly appreciated.
> 
> It should be safe to release the interpreter lock while C++ code is
> executing, provided that C++ doesn't:
> 
> - call, directly or indirectly, any functions from the Python C API 
> - use any C++ objects accessible by other Python threads (if not
> otherwise guarded)
> 
> while this thread doesn't have the lock.
> 
> Ulli 
> -- 
>  ________________________________________________________________
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> | Ullrich Koethe  Universität Hamburg / University of Hamburg    |
> |                 FB Informatik / Dept. of Computer Science      |
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