From: James Westby <jw+debian@jameswestby.net>
To: notmuch@notmuchmail.org
Subject: Re: [PATCH] python: Store pointers as c_void_p to keep references
In-Reply-To: <1322781185-15923-1-git-send-email-jw+debian@jameswestby.net>
References: <87pqg8b9hx.fsf@jameswestby.net>
	<1322781185-15923-1-git-send-email-jw+debian@jameswestby.net>
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Date: Thu, 01 Dec 2011 18:25:43 -0500
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On Thu,  1 Dec 2011 18:13:05 -0500, James Westby <jw+debian@jameswestby.net> wrote:
> From: James Westby <james.westby@linaro.org>
> 
> ctypes doesn't return c_void_p return values as that, it returns them as
> 32-bit integers instead. This has two problems:
> 
>   1 - On 64-bit machines anything higher than the max 32-bit integer
>       will overflow when passed back in to another function expecting,
>       a pointer giving the wrong value.
> 
>   2 - If the value isn't stored as a pointer then the memory can be
>       re-used and so the object will be corrupted.
> 
> The fix for both of these is to store the values as pointers.

http://osdir.com/ml/python.ctypes/2006-12/msg00048.html states that this
is expected behaviour of ctypes.

Thanks,

James