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From: Stefan Behnel <stefan_ml@behnel.de>
Subject: Re: Help with implementing callback functions using ctypes
Date: Thu, 09 May 2013 08:57:55 +0200
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dieter, 09.05.2013 07:54:
> jamadagni writes:
>> ...
> I cannot help you with "ctypes". But, if you might be able to use
> "cython", then calling callbacks is not too difficult

+1 for using Cython. It also has (multi-)source level gdb support, which
greatly helps in debugging crashes like this one.

http://docs.cython.org/src/userguide/debugging.html


> (you can find an example in e.g. my "dm.xmlsec.binding").

An "official" example is here:

https://github.com/cython/cython/tree/master/Demos/callback


> Note, however, that properly handling the GIL ("Global Interpreter Lock")
> may be of great importance when the Python/C boundary is crossed --
> at least when you intend to use your code in a multi thread environment.

Cython makes this really easy. You can use the "with" statement to release
the GIL when you don't need it, and the compiler will produce errors when
you try to do things that require the GIL while you don't own it.

Stefan