Q-Logic IB6054601-00 D Benutzerhandbuch

3 – Using InfiniPath MPI
Configuring MPI Programs for InfiniPath MPI

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IB6054601-00 D

Q

and run it with:

$ mpirun -np 2 -m mpihosts ./pi3f90

The C++ program 

hello++.cc

 is a parallel processing  version of the traditional 

“Hello, World” program.  Notice that this version makes use of the external C 
bindings of the MPI functions if the C++ bindings are not present. 

Compile it:

$ mpicxx -o hello hello++.cc

and run it:

$ mpirun -np 10 -m mpihosts ./hello

Hello World! I am 9 of 10

Hello World! I am 2 of 10

Hello World! I am 4 of 10

Hello World! I am 1 of 10

Hello World! I am 7 of 10

Hello World! I am 6 of 10

Hello World! I am 3 of 10

Hello World! I am 0 of 10

Hello World! I am 5 of 10

Hello World! I am 8 of 10

Each of the scripts invokes the PathScale compiler for the respective language and 
the linker. See 

 for an example of how to use the 

gcc

 compiler. The 

use of 

mpirun

 is the same for programs in all languages.

When configuring an MPI program (generating header files and/or Makefiles), for 
InfiniPath MPI, you will usually need to specify 

mpicc

, 

mpif90

, etc. as the compiler, 

rather than 

pathcc

, 

pathf90

, etc. 

Typically this is done with commands similar to these (this assumes you are using 

sh

 or 

bash

 as your shell):

$ export CC=mpicc

$ export CXX=mpicxx

$ export F77=mpif77

$ export F90=mpif90

$ export F95=mpif95

The shell variables will vary with the program being configured, but these examples 
show frequently used variable names. Users of 

csh

 would instead use commands 

similar to:

$ setenv CC mpicc