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Date: Tue, 18 Mar 2014 18:01:59 -0700
Subject: Re: Controlling buffer alignment in file.read()
From: Dan Stromberg <drsalists@gmail.com>
To: "Haralanov, Mitko" <mitko.haralanov@intel.com>
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On Tue, Mar 18, 2014 at 1:23 PM, Haralanov, Mitko
<mitko.haralanov@intel.com> wrote:
> Hi all,
>
> I am using Python to read from a binary device file which requires that all read sizes are in 8byte multiples and the user's buffer is 8byte aligned.
>
> I am currently using a file object and the file.read() method. However, the issue is that the file.read() method allocates the buffer passed to C function under the covers and, therefore, the alignment is arbitrary.
>
> Is there a way that I can get file.read() to use an 8byte aligned buffer?

This is a lot like what my odirect project does:
http://stromberg.dnsalias.org/~strombrg/odirect/

It does buffer alignment, because O_DIRECT requires buffer alignment.
It's a Python-callable SWIG wrapper for some C code.