[mpich-devel] proper way to detect if program launched by mpiexec?

[Jeff Hammond]

On Mon, Oct 20, 2014 at 11:15 AM, Balaji, Pavan <balaji at anl.gov> wrote:
>
>> On Oct 20, 2014, at 12:43 PM, Jeff Hammond <jeff.science at gmail.com> wrote:
>> Is this because MPICH can't spawn processes except through
>> PMI/Hydra/whatever and you - justifiably - do not want to implement a
>> special case workaround using execvp() directly?
>
> The new process needs a way to query for business cards and such, for which mpiexec is needed.  So the current design of singleton init is to spawn mpiexec and connect to it.  That’s a mess and is not clearly specified by the PMI spec.  My suggestion was to execvp the executable “mpiexec” with the right arguments to relaunch the application again, but there are some problems with that:

Thanks for the info.  I have no problem accepting the terms of MPI-3,
section 8.7, paragraph 1, and forcing myself to use mpiexec.

Jeff

-- 
Jeff Hammond
jeff.science at gmail.com
http://jeffhammond.github.io/