MPI_Info_get_nkeys(3) Gets the number of keys currently defined in an info object.

SYNTAX

C Syntax

#include <mpi.h>
int MPI_Info_get_nkeys(MPI_Info info, int *nkeys)

Fortran Syntax

INCLUDE 'mpif.h'
MPI_INFO_GET_NKEYS(INFO, NKEYS, IERROR)
        INTEGER         INFO, NKEYS, IERROR 

C++ Syntax

#include <mpi.h>
int MPI::Info::Get_nkeys() const

INPUT PARAMETER

info
Info object (handle).

OUTPUT PARAMETERS

nkeys
Number of defined keys (integer).
IERROR
Fortran only: Error status (integer).

DESCRIPTION

MPI_Info_get_nkeys returns the number of currently defined keys in info.

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.

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.