1 /*
2 * Copyright (C) by Argonne National Laboratory
3 * See COPYRIGHT in top-level directory
4 */
5
6 #include <mpi.h>
7 #include <stdio.h>
8 #include "mpitest.h"
9
main(int argc,char ** argv)10 int main(int argc, char **argv)
11 {
12 MPI_Group basegroup;
13 MPI_Group g1, g2;
14 MPI_Comm comm, newcomm, dupcomm;
15 int rank, size;
16 int worldrank;
17 int errs = 0, errclass, mpi_errno;
18
19 MTest_Init(&argc, &argv);
20 MPI_Comm_rank(MPI_COMM_WORLD, &worldrank);
21 comm = MPI_COMM_WORLD;
22 MPI_Comm_group(comm, &basegroup);
23 MPI_Comm_rank(comm, &rank);
24 MPI_Comm_size(comm, &size);
25 MPI_Comm_set_errhandler(MPI_COMM_WORLD, MPI_ERRORS_RETURN);
26
27 MPI_Comm_split(comm, 0, size - rank, &newcomm);
28 MPI_Comm_group(newcomm, &g1);
29 MPI_Comm_dup(comm, &dupcomm);
30 MPI_Comm_group(dupcomm, &g2);
31
32 /* checking group_difference for NULL variable */
33 mpi_errno = MPI_Group_difference(g1, g2, NULL);
34 MPI_Error_class(mpi_errno, &errclass);
35 if (errclass != MPI_ERR_ARG)
36 ++errs;
37
38 MPI_Group_free(&basegroup);
39 MPI_Group_free(&g1);
40 MPI_Group_free(&g2);
41 MPI_Comm_free(&comm);
42 MPI_Comm_free(&newcomm);
43 MPI_Comm_free(&dupcomm);
44 MTest_Finalize(errs);
45 return 0;
46 }
47