.\"Copyright 2006, Sun Microsystems, Inc. All rights reserved. Use is subject to license terms.
.\" Copyright (c) 1996 Thinking Machines Corporation
.TH MPI_Comm_free 3OpenMPI "September 2006" "Open MPI 1.2" " "
.SH NAME
\fBMPI_Comm_free \fP \- Mark a communicator object for deallocation.

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Comm_free(MPI_Comm *\fIcomm\fP)

.SH Fortran Syntax
.nf
INCLUDE 'mpif.h'
MPI_COMM_FREE(\fICOMM, IERROR\fP)
	INTEGER	\fICOMM, IERROR\fP 

.SH C++ Syntax
.nf
#include <mpi.h>
void Comm::Free()

.SH INPUT PARAMETER
.ft R
.TP 1i
comm
Communicator to be destroyed (handle).

.SH OUTPUT PARAMETER
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer). 

.SH DESCRIPTION
.ft R
This operation marks the communicator object for deallocation. The handle is set to MPI_COMM_NULL. Any pending operations that use this communicator will complete normally; the object is actually deallocated only if there are no other active references to it. This call applies to intracommunicators and intercommunicators. Upon actual deallocation, the delete callback functions for all cached attributes (see Section 5.7 in the MPI-1 Standard, "Caching") are called in arbitrary order.  

.SH ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI:Exception object.
.sp
Before the error value is returned, the current MPI error handler is
called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error.  

' @(#)MPI_Comm_free.3 1.20 06/03/09