openmpi/ompi/mpi/man/man3/MPI_Info_get_nkeys.3

.\"Copyright 2006, Sun Microsystems, Inc.
.\" Copyright (c) 1996 Thinking Machines Corporation
.TH MPI_Info_get_nkeys 3OpenMPI "September 2006" "Open MPI 1.2" " "
.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)

.SH Fortran Syntax
.nf
INCLUDE 'mpif.h'
MPI_INFO_GET_NKEYS(\fIINFO, NKEYS, IERROR\fP)
	INTEGER		\fIINFO, NKEYS, IERROR\fP 

.SH C++ Syntax
.nf
#include <mpi.h>
int MPI::Info::Get_nkeys() const

.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. 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.  

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

' @(#)MPI_Info_get_nkeys.3 1.19 06/03/09