1MPI_Op_free(3) LAM/MPI MPI_Op_free(3)
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6 MPI_Op_free - Frees a user-defined combination function handle
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9 #include <mpi.h>
10 int MPI_Op_free(MPI_Op *op)
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13 op - operation (handle)
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17 op is set to MPI_OP_NULL on exit.
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21 The MPI 1.1 specification, in the section on opaque objects, explicitly
22 disallows freeing a null communicator. The text from the standard is
23 "A null handle argument is an erroneous IN argument in MPI calls,
25 unless an exception is explicitly stated in the text that defines the
26 function. Such exception is allowed for handles to request objects in
27 Wait and Test calls (sections Communication Completion and Multiple
28 Completions ). Otherwise, a null handle can only be passed to a
29 function that allocates a new object and returns a reference to it in
30 the handle."
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35 All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
36 an additional argument ierr at the end of the argument list. ierr is
37 an integer and has the same meaning as the return value of the routine
38 in C. In Fortran, MPI routines are subroutines, and are invoked with
39 the call statement.
40 All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
42 Fortran.
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46 If an error occurs in an MPI function, the current MPI error handler is
47 called to handle it. By default, this error handler aborts the MPI
48 job. The error handler may be changed with MPI_Errhandler_set ; the
49 predefined error handler MPI_ERRORS_RETURN may be used to cause error
50 values to be returned (in C and Fortran; this error handler is less
51 useful in with the C++ MPI bindings. The predefined error handler
52 MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value
53 needs to be recovered). Note that MPI does not guarantee that an MPI
54 program can continue past an error.
55 All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
57 value; C routines as the value of the function and Fortran routines in
58 the last argument. The C++ bindings for MPI do not return error val‐
59 ues; instead, error values are communicated by throwing exceptions of
60 type MPI::Exception (but not by default). Exceptions are only thrown
61 if the error value is not MPI::SUCCESS .
62 Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI
65 functions will return upon an error, there will be no way to recover
66 what the actual error value was.
67 MPI_SUCCESS
68 - No error; MPI routine completed successfully.
69 MPI_ERR_ARG
70 - Invalid argument. Some argument is invalid and is not identi‐
71 fied by a specific error class. This is typically a NULL
72 pointer or other such error.
73 MPI_ERR_ARG
74 - Invalid argument; the error code associated with this error
75 indicates an attempt to free an MPI permanent operation (e.g.,
76 MPI_SUM ).
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80 MPI_Op_create
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84 For more information, please see the official MPI Forum web site, which
85 contains the text of both the MPI-1 and MPI-2 standards. These docu‐
86 ments contain detailed information about each MPI function (most of
87 which is not duplicated in these man pages).
88 http://www.mpi-forum.org/
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94 The LAM Team would like the thank the MPICH Team for the handy program
95 to generate man pages ("doctext" from ftp://ftp.mcs.anl.gov/pub/sow‐
96 ing/sowing.tar.gz ), the initial formatting, and some initial text for
97 most of the MPI-1 man pages.
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100 opfree.c
101LAM/MPI 7.1.2 2/23/2006 MPI_Op_free(3)