NAME

       MPI_Op_free - Frees a user-defined combination function handle.

SYNTAX

C Syntax

       #include <mpi.h>
       int MPI_Op_free(MPI_Op *op)

Fortran Syntax

       USE MPI
       ! or the older form: INCLUDE 'mpif.h'
       MPI_OP_FREE(OP, IERROR)
            INTEGER   OP, IERROR

Fortran 2008 Syntax

       USE mpi_f08
       MPI_Op_free(op, ierror)
            TYPE(MPI_Op), INTENT(INOUT) :: op
            INTEGER, OPTIONAL, INTENT(OUT) :: ierror

C++ Syntax

       #include <mpi.h>
       void Op::Free()

INPUT/OUTPUT PARAMETER

       op        Operation (handle).

OUTPUT PARAMETER

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       Marks a user-defined reduction operation for deallocation and sets op to MPI_OP_NULL.

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_Op_create
       MPI_Reduce
       MPI_Allreduce
       MPI_Reduce_scatter
       MPI_Scan