Datatypes

Topology

C | Fortran-2008 | Fortran-90

MPI_COMM_WORLD

Definition

MPI_COMM_WORLD is the communicator provided by MPI; it contains all MPI processes.

Example

Copy

Feedback

#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;
}