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/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *  (C) 2001 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */

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

int main(int argc, char *argv[])
{
    char str[10];
    MPI_Comm intercomm1, intracomm, intercomm2;
    int err, errcodes[256], rank;

    MPI_Init(&argc, &argv);

/*    printf("Child out of MPI_Init\n");
    fflush(stdout);
*/
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    MPI_Comm_get_parent(&intercomm1);

    MPI_Intercomm_merge(intercomm1, 1, &intracomm);

    err = MPI_Comm_spawn("spawn_merge_child2", MPI_ARGV_NULL, 2,
                         MPI_INFO_NULL, 2, intracomm, &intercomm2, errcodes);
    if (err)
        printf("Error in MPI_Comm_spawn\n");

    MPI_Comm_rank(intercomm2, &rank);

    if (rank == 3) {
        err = MPI_Recv(str, 3, MPI_CHAR, 1, 0, intercomm2, MPI_STATUS_IGNORE);
        printf("Parent (first child) received from child 2: %s\n", str);
        fflush(stdout);

        err = MPI_Send("bye", 4, MPI_CHAR, 1, 0, intercomm2);
    }

    MPI_Finalize();
    return 0;
}