+++ /dev/null
-/* -*- Mode: C; -*- */
-/* Creator: Bronis R. de Supinski (bronis@llnl.gov) Fri Mar 17 2000 */
-/* no-error.c -- do some MPI calls without any errors */
-
-#include <stdio.h>
-#include "mpi.h"
-
-#define buf_size 128
-
-int
-main (int argc, char **argv)
-{
- int nprocs = -1;
- int rank = -1;
- char processor_name[128];
- int namelen = 128;
- int buf0[buf_size];
- int buf1[buf_size];
- MPI_Status status;
- MPI_Comm comm;
- MPI_Group world_group, dgroup;
- int *granks;
- int i, drank, dnprocs, newsize;
-
- /* init */
- MPI_Init (&argc, &argv);
- MPI_Comm_size (MPI_COMM_WORLD, &nprocs);
- MPI_Comm_rank (MPI_COMM_WORLD, &rank);
- MPI_Get_processor_name (processor_name, &namelen);
- printf ("(%d) is alive on %s\n", rank, processor_name);
- fflush (stdout);
-
- MPI_Barrier (MPI_COMM_WORLD);
-
- if (nprocs < 3) {
- printf ("not enough tasks\n");
- }
- else {
- MPI_Comm_group (MPI_COMM_WORLD, &world_group);
- if (nprocs % 2)
- newsize = (nprocs/2) + 1;
- else
- newsize = nprocs/2;
- granks = (int *) malloc (sizeof(int) * (newsize));
- for (i = 0; i < newsize; i++)
- granks [i] = 2 * i;
- MPI_Group_incl (world_group, newsize, granks, &dgroup);
- MPI_Comm_create (MPI_COMM_WORLD, dgroup, &comm);
- MPI_Group_free (&world_group);
- MPI_Group_free (&dgroup);
- free (granks);
-
- if (comm != MPI_COMM_NULL) {
- MPI_Comm_size (comm, &dnprocs);
- MPI_Comm_rank (comm, &drank);
-
- if (dnprocs > 1) {
- if (drank == 0) {
- memset (buf0, 0, buf_size);
-
- MPI_Recv (buf1, buf_size, MPI_INT, 1, 0, comm, &status);
-
- MPI_Send (buf0, buf_size, MPI_INT, 1, 0, comm);
- }
- else if (drank == 1) {
- memset (buf1, 1, buf_size);
-
- MPI_Recv (buf0, buf_size, MPI_INT, 0, 0, comm, &status);
-
- MPI_Send (buf1, buf_size, MPI_INT, 0, 0, comm);
- }
- }
- else {
- printf ("(%d) Derived communicator too small (size = %d)\n",
- rank, dnprocs);
- }
-
- MPI_Comm_free (&comm);
- }
- else {
- printf ("(%d) Got MPI_COMM_NULL\n", rank);
- }
- }
-
- MPI_Barrier (MPI_COMM_WORLD);
-
- MPI_Finalize ();
- printf ("(%d) Finished normally\n", rank);
-}
-
-/* EOF */