.\" -*- nroff -*-
.\" Copyright 2010 Cisco Systems, Inc.  All rights reserved.
.\" Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.\" Copyright 2015      Research Organization for Information Science
.\"                     and Technology (RIST). All rights reserved.
.\" $COPYRIGHT$
.TH MPI_File_get_group 3 "Jan 31, 2017" "2.0.2" "Open MPI"
.SH NAME
\fBMPI_File_get_group\fP \- Returns a duplicate of the process group of a file.

.SH SYNTAX
.ft R
.nf
.SH C Syntax
#include <mpi.h>
int MPI_File_get_group(MPI_File \fIfh\fP, MPI_Group \fI*group\fP)

.fi
.SH Fortran Syntax
.nf
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_FILE_GET_GROUP(\fIFH\fP, \fIGROUP\fP, \fIIERROR\fP)
	INTEGER	\fIFH, GROUP, IERROR\fP

.fi
.SH C++ Syntax
.nf
#include <mpi.h>
MPI::Group MPI::File::Get_group() const

.fi
.SH INPUT PARAMETER
.ft R
.TP 1i
fh
File handle (handle).

.SH OUTPUT PARAMETERS
.TP 1i
group
Group that opened the file (handle).
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
MPI_File_get_group returns a duplicate of the group of the communicator
used to open the file associated with
.I fh.
The group is returned in
.I group.
The user is responsible for freeing
.I group,
using MPI_Group_free.

.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. For MPI I/O function errors, the default error handler is set to MPI_ERRORS_RETURN. The error handler may be changed with MPI_File_set_errhandler; the predefined error handler MPI_ERRORS_ARE_FATAL may be used to make I/O errors fatal. Note that MPI does not guarantee that an MPI program can continue past an error.