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Re: Controlling buffer alignment in file.read()

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From Gregory Ewing <greg.ewing@canterbury.ac.nz>
Newsgroups comp.lang.python
Subject Re: Controlling buffer alignment in file.read()
Date Wed, 19 Mar 2014 13:07:12 +1300
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Haralanov, Mitko wrote:

> The problem is not controlling the number of bytes read. That part seems to
> be working. The issue is that the buffer into which the data is placed needs
> to be of certain alignment (8byte-aligned). Python does not seem to have a
> way that allows me to control that.

Hmmm, that could be tricky. Have you tried using os.read()?
If you're lucky, Python will be using a malloc() call or
equivalent to create a str/bytes object to read the data
into, and that will return something platform-aligned.

If you're unlucky, there's probably no pure-Python
solution, and you might need to write a small C or
Cython module to accomplish this trick.


-- 
Greg

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Thread

Controlling buffer alignment in file.read() "Haralanov, Mitko" <mitko.haralanov@intel.com> - 2014-03-18 20:23 +0000
  Re: Controlling buffer alignment in file.read() Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-19 12:08 +1300
    RE: Controlling buffer alignment in file.read() "Haralanov, Mitko" <mitko.haralanov@intel.com> - 2014-03-18 23:13 +0000
      Re: Controlling buffer alignment in file.read() Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2014-03-19 13:07 +1300
      RE: Controlling buffer alignment in file.read() Laurent Pointal <laurent.pointal@free.fr> - 2014-03-22 19:28 +0100

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