openmpi/ompi/mpi/man/man3/MPI_Win_get_attr.3in

.\" -*- nroff -*-
.\" Copyright 2010 Cisco Systems, Inc.  All rights reserved.
.\" Copyright 2006-2008 Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.\" Copyright (c) 2020      Google, LLC. All rights reserved.
.\" $COPYRIGHT$
.TH MPI_Win_get_attr 3 "#OMPI_DATE#" "#PACKAGE_VERSION#" "#PACKAGE_NAME#"
.SH NAME
\fBMPI_Win_get_attr\fP \- Obtains the value of a window attribute.

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Win_get_attr(MPI_Win \fIwin\fP, int \fIwin_keyval\fP,
	void *\fIattribute_val\fP, int *\fIflag\fP)

.fi
.SH Fortran Syntax (see FORTRAN 77 NOTES)
.nf
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_WIN_GET_ATTR(\fIWIN, WIN_KEYVAL, ATTRIBUTE_VAL, FLAG, IERROR\fP)
	INTEGER \fIWIN, WIN_KEYVAL, IERROR\fP
	INTEGER(KIND=MPI_ADDRESS_KIND) \fIATTRIBUTE_VAL\fP
	LOGICAL \fIFLAG\fP

.fi
.SH Fortran 2008 Syntax
.nf
USE mpi_f08
MPI_Win_get_attr(\fIwin\fP, \fIwin_keyval\fP, \fIattribute_val\fP, \fIflag\fP, \fIierror\fP)
	TYPE(MPI_Win), INTENT(IN) :: \fIwin\fP
	INTEGER, INTENT(IN) :: \fIwin_keyval\fP
	INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(OUT) :: \fIattribute_val\fP
	LOGICAL, INTENT(OUT) :: \fIflag\fP
	INTEGER, OPTIONAL, INTENT(OUT) :: \fIierror\fP

.fi
.SH INPUT PARAMETERS
.ft R
.TP 1i
win
Window to which the attribute is attached (handle).
.TP 1i
win_keyval
Key value (integer).

.SH OUTPUT PARAMETERS
.ft R
.TP 1i
attribute_val
Attribute value, unless \fIag\fP = false
.TP 1i
flag
False if no attribute is associated with the key (logical).
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
Obtains the value of a window attribute.
.SH FORTRAN 77 NOTES
.ft R
The MPI standard prescribes portable Fortran syntax for
the \fIATTRIBUTE_VAL\fP argument only for Fortran 90. FORTRAN 77
users may use the non-portable syntax
.sp
.nf
     INTEGER*MPI_ADDRESS_KIND \fIATTRIBUTE_VAL\fP
.fi
.sp
where MPI_ADDRESS_KIND is a constant defined in mpif.h
and gives the length of the declared integer in bytes.

.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.
.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.