#include #include #include #include #include #include #include "mpi.h" int main( int argc, char **argv ) { MPI_Comm parent; MPI_Comm merged; int rank; int size; MPI_Init(&argc, &argv); printf("Child: launch\n"); MPI_Comm_get_parent(&parent); MPI_Intercomm_merge(parent, 1, &merged); MPI_Comm_rank(merged, &rank); MPI_Comm_size(merged, &size); printf("Child merged rank = %d, size = %d\n", rank, size); MPI_Comm_free(&merged); MPI_Finalize(); printf("Child %d: exiting\n", (int)getpid()); return 0; }