MPI_Op_free
Frees a user-defined combination function handle
Synopsis
#include "mpi.h"
int MPI_Op_free( MPI_Op *op )
Input Parameter
- op
- operation (handle)
Notes
op is set to MPI_OP_NULL on exit.
Null Handles
The MPI 1.1 specification, in the section on opaque objects, explicitly
disallows freeing a null communicator. The text from the standard is
A null handle argument is an erroneous IN argument in MPI calls, unless an
exception is explicitly stated in the text that defines the function. Such
exception is allowed for handles to request objects in Wait and Test calls
(sections Communication Completion and Multiple Completions ). Otherwise, a
null handle can only be passed to a function that allocates a new object and
returns a reference to it in the handle.
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_Errhandler_set; 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.
- 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
- Invalid argument; the error code associated with this
error indicates an attempt to free an MPI permanent operation (e.g.,
MPI_SUM).
*N/
/*N MPI_ERR_PERM_KEY
- MPI_ERR_ARG
- Invalid argument; the error code associated with this
error indicates an attempt to free or chnage an MPI permanent keyval (e.g.,
MPI_TAG_UB).
*N/
/*N MPI_ERR_UNKNOWN
- MPI_ERR_UNKNOWN
- Unknown error. You should never see this. If you
do, report it to mpi-bugs@mcs.anl.gov.
See Also
MPI_Op_create
Location:opfree.c