Example: Spawning a Manager/Worker Application
MPI_Attr_get(MPI_COMM_WORLD, MPI_UNIVERSE_SIZE,
&univ_size, &flag); /* processes that can start */
MPI_Comm_spawn( worker, MPI_ARGV_NULL, univ_size-1, MPI_INFO_NULL, 0, MPI_COMM_SELF, &communicator, MPI_ERRCODES_IGNORE );
* Interaction with workers goes here, using communicator
MPI_Comm_get_parent( &mom );
* Real work goes here, through mom