[MPICH] MPI_Comm_size on parent communicator

[Wei-keng Liao]

Can I call MPI_Comm_size to get the size of a parent communicator (an 
inter-communicator)?

My program is in a client-server model and clients spawn a group of 
servers through MPI_Comm_spawn. On the server size, there are 2 calls:
    MPI_Comm_get_parent(&client_comm);
    MPI_Comm_size(client_comm, &client_nproc);

Should the MPI_Comm_size() return the size of the clients?
I tried this on mpich2-1.0.6p1 and it did not give me the right 
number.

Wei-keng