MPI_Group smpi_comm_group(MPI_Comm comm);
int smpi_comm_size(MPI_Comm comm);
int smpi_comm_rank(MPI_Comm comm);
+MPI_Comm smpi_comm_split(MPI_Comm comm, int color, int key);
MPI_Request smpi_mpi_send_init(void *buf, int count, MPI_Datatype datatype,
int dst, int tag, MPI_Comm comm);