Re: OpenMP, OMP_NUM_THREADS and putenv - not working as expected.

[Chi Chan]

Which implementation of compiler are you using?

--Chi



On Wed, Apr 14, 2010 at 8:38 AM, coccoinomane <address@hidden> wrote:
>
> Hello world!
>
> I do not know if this is a bug or if I am missing something obvious.
>
> I am successfully using Octave to run a parallel C++ code trough the
> oct-file interface. I implemented the parallellism at the C++ level with
> OpenMP and its #pragma directives.
>
> I control the number of threads used by my program through the environment
> variable OMP_NUM_THREADS. When I launch Octave from a shell where
> OMP_NUM_THREADS is correctly exported, my program correctly uses the
> specified number of threads.
>
> However, when I try to change the environment variable from within Octave
> with putenv - for example putenv ("OMP_NUM_THREADS", "1") - and then re-run
> the oct-file function, the latter keeps using the initial number of threads
> (i.e. the one specified prior to launching Octave at the shell level). It is
> like my  "putenv" command was ignored. However, "getenv ("OMP_NUM_THREADS")"
> correctly returns the modified value, i.e. "1".
>
> Right now, as a workaround, every time I want to change the number of
> threads I close and relaunch Octave. This is not very practical. I would be
> grateful if somebody could give me a hint.
>
> Thank you!
>
> Cheers,
>
> Guido
>
>
>
>
> --
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> http://n4.nabble.com/OpenMP-OMP-NUM-THREADS-and-putenv-not-working-as-expected-tp1839801p1839801.html
> Sent from the Octave - General mailing list archive at Nabble.com.
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