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From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Interfacing a dynamic shared library gives me different results in 2.7 versus 3.5
Date: Wed, 25 May 2016 02:45:30 +1000
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On Wed, May 25, 2016 at 2:32 AM, Steven D'Aprano <steve@pearwood.info> wrote:
> On Wed, 25 May 2016 02:18 am, Siyi Deng wrote:
>
>> Hello ChrisA,
>> I don't quite understand, the binary shared library contains no python
>> interfaces, it should be independent of python.
>
> In your first post, you said you were using numpy. How is that independent
> of Python?

I'm not certain of the in-memory representation of a numpy array, but
it wouldn't surprise me if it's just a series of consecutive
ints/floats - which would be exactly what a C or Fortran library will
be expecting. So my understanding is that there's some basic ctypes
wrapper code to locate the base address of the array, and then it
passes that straight along.

Of course, without seeing the code....

ChrisA