.\" -*- 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_Info_get_nkeys 3 "#OMPI_DATE#" "#PACKAGE_VERSION#" "#PACKAGE_NAME#"
.SH NAME
\fBMPI_Info_get_nkeys\fP \- Gets the number of keys currently defined in an info object.

.SH SYNTAX
.ft R
.SH C Syntax
.nf
#include <mpi.h>
int MPI_Info_get_nkeys(MPI_Info \fIinfo\fP, int \fI*nkeys\fP)

.fi
.SH Fortran Syntax
.nf
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_INFO_GET_NKEYS(\fIINFO, NKEYS, IERROR\fP)
	INTEGER		\fIINFO, NKEYS, IERROR\fP

.fi
.SH Fortran 2008 Syntax
.nf
USE mpi_f08
MPI_Info_get_nkeys(\fIinfo\fP, \fInkeys\fP, \fIierror\fP)
	TYPE(MPI_Info), INTENT(IN) :: \fIinfo\fP
	INTEGER, INTENT(OUT) :: \fInkeys\fP
	INTEGER, OPTIONAL, INTENT(OUT) :: \fIierror\fP

.fi
.SH INPUT PARAMETER
.ft R
.TP 1i
info
Info object (handle).

.SH OUTPUT PARAMETERS
.ft R
.TP 1i
nkeys
Number of defined keys (integer).
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer).

.SH DESCRIPTION
.ft R
MPI_Info_get_nkeys returns the number of currently defined keys in \fIinfo\fP.

.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.

.SH SEE ALSO
.ft r
MPI_Info_get
.br
MPI_Info_get_nthkey
.br
MPI_Info_get_valuelen
.br