1 /* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
3 * (C) 2001 by Argonne National Laboratory.
4 * See COPYRIGHT in top-level directory.
8 /* stdlib.h Needed for malloc declaration */
11 int main( int argc, char **argv )
13 int i, n, n_goal = 2048, n_all, rc, n_ranks, *ranks, rank, size, len;
15 MPI_Group *group_array, world_group;
16 char msg[MPI_MAX_ERROR_STRING];
18 MPI_Init( &argc, &argv );
19 MPI_Comm_size( MPI_COMM_WORLD, &size );
20 MPI_Comm_rank( MPI_COMM_WORLD, &rank );
23 group_array = (MPI_Group *)malloc( n * sizeof(MPI_Group) );
25 MPI_Comm_group( MPI_COMM_WORLD, &world_group );
28 ranks = (int *)malloc( size * sizeof(int) );
29 for (i=0; i<size; i++) ranks[i] = i;
31 MPI_Errhandler_set( MPI_COMM_WORLD, MPI_ERRORS_RETURN );
33 rc = MPI_Group_incl( world_group, n_ranks, ranks, group_array + i );
35 fprintf( stderr, "Error when creating group number %d\n", i );
36 MPI_Error_string( rc, msg, &len );
37 fprintf( stderr, "%s\n", msg );
42 /* Check that the group was created (and that any errors were
44 MPI_Group_size( group_array[i], &group_size );
45 if (group_size != size) {
46 fprintf( stderr, "Group number %d not correct (size = %d)\n",
56 rc = MPI_Group_free( group_array + i );
58 fprintf( stderr, "Error when freeing group number %d\n", i );
59 MPI_Error_string( rc, msg, &len );
60 fprintf( stderr, "%s\n", msg );
65 MPI_Errhandler_set( MPI_COMM_WORLD, MPI_ERRORS_ARE_FATAL );
66 MPI_Group_free( &world_group );
68 MPI_Reduce( &n, &n_all, 1, MPI_INT, MPI_MIN, 0, MPI_COMM_WORLD );
70 /* printf( "Completed test of %d type creations\n", n_all ); */
71 if (n_all != n_goal) {
73 "This MPI implementation limits the number of groups that can be created\n\
74 This is allowed by the standard and is not a bug, but is a limit on the\n\
78 printf( " No Errors\n" );