MPI_Keyval_free

 Frees an attribute key for communicators

Synopsis

int MPI_Keyval_free(int *keyval)

Input Parameters

keyval
Frees the integer key value (integer)

Note

Key values are global (they can be used with any and all communicators)

Deprecated Function

The MPI-2 standard deprecated a number of routines because MPI-2 provides better versions. This routine is one of those that was deprecated. The routine may continue to be used, but new code should use the replacement routine. The replacement for this routine is MPI_Comm_free_keyval.

Thread and Interrupt Safety

This routine is thread-safe. This means that this routine may be safely used by multiple threads without the need for any user-provided thread locks. However, the routine is not interrupt safe. Typically, this is due to the use of memory allocation routines such as malloc or other non-MPICH runtime routines that are themselves not interrupt-safe.

Notes for Fortran

All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK) have an additional argument ierr at the end of the argument list. ierr is an integer and has the same meaning as the return value of the routine in C. In Fortran, MPI routines are subroutines, and are invoked with the call statement.

All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type INTEGER in Fortran.

Errors

All MPI routines (except MPI_Wtime and MPI_Wtick) return an error value; C routines as the value of the function and Fortran routines in the last argument. Before the value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job. The error handler may be changed with MPI_Comm_set_errhandler (for communicators), MPI_File_set_errhandler (for files), and MPI_Win_set_errhandler (for RMA windows). The MPI-1 routine MPI_Errhandler_set may be used but its use is deprecated. The predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarentee that an MPI program can continue past an error; however, MPI implementations will attempt to continue whenever possible.

MPI_SUCCESS
No error; MPI routine completed successfully.
MPI_ERR_ARG
Invalid argument. Some argument is invalid and is not identified by a specific error class (e.g., MPI_ERR_RANK).
MPI_ERR_ARG
This error class is associated with an error code that indicates that an attempt was made to free one of the permanent keys.

See Also MPI_Keyval_create, MPI_Comm_free_keyval