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Date: Sun, 28 Oct 2012 01:56:47 +1100
Subject: Re: ctypes free memory which is allocated in C DLL
From: Chris Angelico <rosuav@gmail.com>
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Xref: csiph.com comp.lang.python:32282

On Sun, Oct 28, 2012 at 1:42 AM,  <zlchen.ken@gmail.com> wrote:
> Hi Guys,
>
> I have a DLL which written in C language, one of the function is to alloc=
ate a structure, fill the members and then return the pointer of the struct=
ure.
>
> After Python called this function, and done with the returned structure, =
I would like to free the returned structure. How can I achieve this ? Basic=
ally, I tried that I wrote a corresponding free interface in the DLL, it wo=
rks, but calling the libc.free in Python doesn't work.

As a general rule, you should always match your allocs and frees. Use
the same library to free the memory as was used to allocate it.
Nothing else is safe. If your DLL exposes an API that allocates
memory, your DLL should expose a corresponding API to free it. So what
you have is the best way :)

ChrisA