You could use MPI_Comm_disconnect. The description is in the 3.1 standard p. 398: This function waits for all pending communication on comm to complete internally, deallocates the communicator object, and sets the handle to MPI_COMM_NULL. It is a collective operation. If you disconnect the communicator from MPI_Comm_get_parent before you call MPI_Finalize and the spawning processes do the same, you should synchronize around the disconnect. On Feb 17, 2017, at 7:58 AM, Dorier, Matthieu <[email protected]<mailto:[email protected]>> wrote: Hi, If I have an application that calls MPI_Comm_spawn, is there a way to make the parent "wait" for the child application to have called MPI_Finalize (or terminated), at some point? The rational would be that MPI_Comm_spawn is sort of an MPI equivalent of "fork/execv", but I don't see an equivalent of "wait", in the standard. My feeling is that once a child application is spawned, it is supposed to stay alive until the parent calls MPI_Finalize as well. Am I mistaken? Thanks, Matthieu _______________________________________________ discuss mailing list [email protected]<mailto:[email protected]> To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss _______________________________________________ discuss mailing list [email protected] To manage subscription options or unsubscribe: https://lists.mpich.org/mailman/listinfo/discuss