openmpi/examples/README

Copyright (c) 2004-2006 The Trustees of Indiana University and Indiana
                        University Research and Technology
                        Corporation.  All rights reserved.
Copyright (c) 2006-2011 Cisco Systems, Inc.  All rights reserved.
Copyright (c) 2007-2009 Sun Microsystems, Inc.  All rights reserved.
Copyright (c) 2010      Oracle and/or its affiliates.  All rights reserved.

The files in this directory are sample MPI applications provided both
as a trivial primer to MPI as well as simple tests to ensure that your
Open MPI installation is working properly.

If you are looking for a comprehensive MPI tutorial, these samples are
not enough.  Excellent MPI tutorials are available here:

        http://www.citutor.org/login.php

Get a free account and login; you can then browse to the list of
available courses.  Look for the ones with "MPI" in the title.

There are 2 MPI examples in this directory, each in four languages:

- Hello world
  C:   hello_c.c
  C++: hello_cxx.cc
  F77: hello_f77.f
  F90: hello_f90.f90

- Send a trivial message around in a ring
  C:   ring_c.c
  C++: ring_cxx.cc
  F77: ring_f77.f
  F90: ring_f90.f90

- Test the connectivity between all processes
  C:   connectivity_c.c

The Makefile in this directory will build as many of the examples as
you have language support (e.g., if you do not have F90 bindings
compiled as part of Open MPI, the F90 examples will be skipped).

The Makefile assumes that the wrapper compilers mpicc, mpic++, mpif77,
and mpif90 are in your path.

Although the Makefile is tailored for Open MPI (e.g., it checks the
"ompi_info" command to see if you have support for C++, F77, and F90),
all of the example programs are pure MPI, and therefore not specific
to Open MPI.  Hence, you can use a different MPI implementation to
compile and run these programs if you wish.

Make today an Open MPI day!