CFD Online Discussion Forums - How to extract MPI rank?

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How to extract MPI rank?

Hello Friends,
I'm wondering how to extract MPI rank in OpenFOAM?
In general, I think this would work:

Code:

#include"mpi.h"



int main(int argc , char **argv)

{

int size,rank;

MPI_Init(&argc, &argv);

MPI_Comm_size(MPI_COMM_WORLD, &size);

MPI_Comm_rank(MPI_COMM_WORLD, &rank);



Info << "rank: " << rank << nl << endl;

}

But I meet the error:

Code:

Fatal error in PMPI_Init_thread: Other MPI error, error stack:

MPI_Init_thread(1028): Cannot call MPI_INIT or MPI_INIT_THREAD more than once

I am using Intel(R) MPI by the way.

Thanks a lot

solved,
for people who meet the same problem,
use

Code:

rank = Pstream::myProcNo();

Pout << "rank: " << rank << nl << endl;