If an MPI_Irecv has already been posted, and a single message is sent
to the receiver, then will an MPI_Probe return that there is no
message waiting to be received? The message has already been received
by the MPI_Irecv. It's the MPI_Request object of the MPI_Irecv call
that needs to be probed, but MPI_Test has the side effect of also
deallocating the MPI_Request object.
> Have you tried MPI_Probe?
> Shaun Jackman wrote:
>> Is there a function similar to MPI_Test that doesn't deallocate the
>> MPI_Request object? I would like to test if a message has been
>> received (MPI_Irecv), check its tag, and dispatch the MPI_Request to
>> another function based on that tag.