Re: Copying void * string to

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From	Ian Kelly <ian.g.kelly@gmail.com>
Newsgroups	comp.lang.python
Subject	Re: Copying void * string to
Date	Wed, 10 Feb 2016 08:30:16 -0700
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On Wed, Feb 10, 2016 at 5:07 AM, Martin Phillips
<martinphillips@ladybridge.com> wrote:
> I am writing a Python wrapper to go around a C library. I have encountered a problem that I have been unable to resolve with
> countless web searches.
>
>
>
> Several functions in the C library return pointers to dynamically allocated w_char null terminated strings. I need to copy the
> string to a Python variable and call an existing library function that will free the dynamically allocate memory.
>
>
>
> My test code for this is
>
>
>
> def Test(fno, item):
>
>     func = mylib. MyFunc
>
>     func.restype = ct.c_void_p
>
>     s = func(fno, item)
>
>     result = s
>
>     mylib.free(s)
>
>     return result
>
>
>
> The problem is with the line that sets the result variable. I need this to make a copy of the dynamically allocated string, not the
> pointer to it.

Does ctypes.wstring_at(s) do what you want?

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Re: Copying void * string to Ian Kelly <ian.g.kelly@gmail.com> - 2016-02-10 08:30 -0700

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