/*D
   MPI_Comm_get_parent - Return the parent communicator for this process

Synopsis:
.vb
int MPI_Comm_get_parent(MPI_Comm *parent)
.ve

Output Parameters:
. parent - the parent communicator (handle)

Notes:
If a process was started with 'MPI_Comm_spawn' or 'MPI_Comm_spawn_multiple',
'MPI_Comm_get_parent' returns the parent intercommunicator of the current
process. This parent intercommunicator is created implicitly inside of
'MPI_Init' and is the same intercommunicator returned by 'MPI_Comm_spawn'
in the parents.

If the process was not spawned, 'MPI_Comm_get_parent' returns
'MPI_COMM_NULL'.

After the parent communicator is freed or disconnected, 'MPI_Comm_get_parent'
returns 'MPI_COMM_NULL'.

.N ThreadSafe

.N Fortran

.N Errors
.N MPI_SUCCESS
.N MPI_ERR_ARG
.N MPI_ERR_OTHER

D*/

