MPI Subroutine Reference

MPI_COMM_TEST_INTER, MPI_Comm_test_inter

Purpose

Returns the type of a communicator (intra- or inter-).

C synopsis

#include <mpi.h>
int MPI_Comm_test_inter(MPI_Comm comm,int *flag);

C++ synopsis

#include mpi.h
bool MPI::Comm::Is_inter() const;

FORTRAN synopsis

include 'mpif.h' or use mpi
MPI_COMM_TEST_INTER(INTEGER COMM,LOGICAL FLAG,INTEGER IERROR)

Parameters

comm

is the communicator (handle) (INOUT)

flag

communicator type (logical)

IERROR

is the FORTRAN return code. It is always the last argument.

Description

This subroutine is used to determine if a communicator is an inter- or intracommunicator.

If comm is an intercommunicator, the call returns true. If comm is an intracommunicator, the call returns false.

Notes

Though many subroutines accept either an intercommunicator or an intracommunicator, the usage and semantic can be quite different.

Errors

Invalid communicator

MPI not initialized

MPI already finalized