I am trying to experiment with openmpi and following trivial code (although runs) affects value of errno

#include <cerrno>
#include <mpi.h>

int main(int argc, char** argv)
{
     int _procid, _np;
     std::cout << "errno=\t" << errno << std::endl;
     MPI_Init(&argc, &argv);
     std::cout << "errno=\t" << errno << "\tafter MPI_Init()\t" << std::endl;
     MPI_Comm_rank (MPI_COMM_WORLD, &_procid);
     MPI_Comm_size (MPI_COMM_WORLD, &_np);
     std::cout << "errno msg=\t" << strerror(errno) << "\tprocessor=\t" << _procid << std::endl;
     MPI_Finalize();
     return 0;
}

Compiled with
mpiCC -Wall test.cpp -o test

Produces following output when run just on single processor using
mpirun -np 1 --prefix /toolbox/openmpi  ./test
errno=  0
errno=  2       after MPI_Init()
errno msg=      No such file or directory       processor=      0

When run on two processors using
mpirun -np 2 --prefix /toolbox/openmpi  ./test
errno=  0
errno=  0
errno=  11      after MPI_Init()
errno=  115     after MPI_Init()
errno msg=      Operation now in progress       processor=      0
errno msg=      Resource temporarily unavailable        processor=      1

The output of ompi_info --all is attached

<<ompi_info.txt>>

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