Newsgroups: comp.parallel.mpi
From: Mohammad Hamdan <hamdan@cee.hw.ac.uk>
Subject: problem with mpi (invalid communicator)
Organization: Heriot-Watt University
Date: Thu, 05 Dec 1996 03:46:06 +0000
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Message-ID: <32A6457E.41C67EA6@cee.hw.ac.uk>

Hi all, 

I'm using the epcc's release of mpi for the meiko. I keep
getting this run-time error: MPI_Ssend: invalid communicator. The
corresponding command for this error is a simple MPI_Ssend(...) I've
replaced this line with MPI_Comm_rank(MPI_COMM_WORLD, &rank) and I got
the same run-time error. 

Please note that this error happens in one of the functions that I call
from the main program.
In the main program, MPI_Init(), MPI_Comm_rank(), and MPI_Comm_size()
work fine. It is only inside one of the functions. I think that mpi at a
certain level looses control of MPI_COMM_WORLD and all commands that
need to access this communicator report this run-time error. The
commands that I use in my program are simply: MPI_Ssend(), MPI_Recv(),
MPI_Probe() and MPI_Get_count(). 

I hope that someone can help by at least suggesting what might cause
such an error.

I can send code if someone is willing to look deeply.

Please reply by e-mail to hamdan@cee.hw.ac.uk if possible.

Thanks in advance,

Mohammad

