Provided by: openmpi-doc_1.6.5-8_all 

NAME
MPI_Info_get_nkeys - 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.
SEE ALSO
MPI_Info_get
MPI_Info_get_nthkey
MPI_Info_get_valueln
1.6.5 Jun 26, 2013 MPI_Info_get_nkeys(3)