NAME¶

MPI_Info_get_nthkey - Returns the nth defined key in info.

SYNTAX¶

C Syntax¶

#include <mpi.h>
int MPI_Info_get_nthkey(MPI_Info info, int n, char *key)

Fortran Syntax¶

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_INFO_GET_NTHKEY(INFO, N, KEY, IERROR)
	INTEGER		INFO, N, IERROR
	CHARACTER*(*)	KEY

Fortran 2008 Syntax¶

USE mpi_f08
MPI_Info_get_nthkey(info, n, key, ierror)
	TYPE(MPI_Info), INTENT(IN) :: info
	INTEGER, INTENT(IN) :: n
	CHARACTER(LEN=*), INTENT(OUT) :: key
	INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax¶

#include <mpi.h>
void MPI::Info::Get_nthkey(int n, char* key) const

INPUT PARAMETERS¶

info

Info object (handle).

n

Key number (integer).

OUTPUT PARAMETERS¶

key

Key (string).

IERROR

Fortran only: Error status (integer).

DESCRIPTION¶

MPI_Info_get_nthkey returns the nth defined key in info. Keys are numbered 0...N - 1 where N is the value returned by MPI_Info_get_nkeys. All keys between 0 and N - 1 are guaranteed to be defined. The number of a given key does not change as long as info is not modified with MPI_Info_set or MPI_Info_delete.

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_nkeys
MPI_Info_get_valuelen