/*
 * Copyright (c) 2020, Dive into Systems, LLC
 * https://diveintosystems.org/
 */

#include <stdio.h>
#include <unistd.h>
#include "mpi.h"

int main(int argc, char **argv) {
    int rank, process_count;
    char hostname[1024];

    /* Initialize MPI. */
    MPI_Init(&argc, &argv);

    /* Determine how many processes there are and which one this is. */
    MPI_Comm_size(MPI_COMM_WORLD, &process_count);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    /* Determine the name of the machine this process is running on. */
    gethostname(hostname, 1024);

    /* Print a message, identifying the process and machine it comes from. */
    printf("Hello from %s process %d of %d\n", hostname, rank, process_count);

    /* Clean up. */
    MPI_Finalize();

    return 0;
}