Datatypes
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C | FORTRAN-legacy | FORTRAN-2008
MPI_COMM_WORLD
Definition
MPI_COMM_WORLD is the communicator provided by MPI; it contains all MPI processes.
Example
#include <stdio.h>
#include <stdlib.h>
#include <mpi.h>
/**
* @brief For each process in the default communicator MPI_COMM_WORLD, show their rank.
**/
int main(int argc, char* argv[])
{
MPI_Init(&argc, &argv);
int my_rank;
MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
printf("I am MPI process %d.\n", my_rank);
MPI_Finalize();
return EXIT_SUCCESS;
}