1MPI_Win_fence(3) LAM/MPI MPI_Win_fence(3)
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6 MPI_Win_fence - Synchronizes one-sided communications on a window
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9 #include <mpi.h>
10 int
11 MPI_Win_fence(int assertion, MPI_Win win)
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14 assertion
15 - program assertion (integer)
16 win - window object (handle)
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20 The MPI call MPI_WIN_FENCE(assert, win) synchronizes RMA calls on win.
21 The call is collective on the group of win. All RMA operations on win
22 originating at a given process and started before the fence call will
23 complete at that process before the fence call returns. They will be
24 completed at their target before the fence call returns at the target.
25 RMA operations on win started by a process after the fence call returns
26 will access their target window only after MPI_WIN_FENCE has been
27 called by the target process.
28 Calls to MPI_WIN_FENCE should both precede and follow calls to put, get
30 or accumulate that are synchronized with fence calls.
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34 All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK ) have
35 an additional argument ierr at the end of the argument list. ierr is
36 an integer and has the same meaning as the return value of the routine
37 in C. In Fortran, MPI routines are subroutines, and are invoked with
38 the call statement.
39 All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in
41 Fortran.
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44 The IMPI standard only supports MPI-1 functions. Hence, this function
45 is currently not designed to operate within an IMPI job.
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49 If an error occurs in an MPI function, the current MPI error handler is
50 called to handle it. By default, this error handler aborts the MPI
51 job. The error handler may be changed with MPI_Errhandler_set ; the
52 predefined error handler MPI_ERRORS_RETURN may be used to cause error
53 values to be returned (in C and Fortran; this error handler is less
54 useful in with the C++ MPI bindings. The predefined error handler
55 MPI::ERRORS_THROW_EXCEPTIONS should be used in C++ if the error value
56 needs to be recovered). Note that MPI does not guarantee that an MPI
57 program can continue past an error.
58 All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error
60 value; C routines as the value of the function and Fortran routines in
61 the last argument. The C++ bindings for MPI do not return error val‐
62 ues; instead, error values are communicated by throwing exceptions of
63 type MPI::Exception (but not by default). Exceptions are only thrown
64 if the error value is not MPI::SUCCESS .
65 Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI
68 functions will return upon an error, there will be no way to recover
69 what the actual error value was.
70 MPI_SUCCESS
71 - No error; MPI routine completed successfully.
72 MPI_ERR_WIN
73 - Invalid window. A common error is to use a null window in a
74 call.
75 MPI_ERR_EPOCH
76 - This error indicates than an operation has been attempted on a
77 "closed" window. Certain one-sided operations can only be per‐
78 formed on windows whose epoch has been started with
79 MPI_Win_start.
80 MPI_ERR_OTHER
81 - Other error; use MPI_Error_string to get more information
82 about this error code.
83 seealso MPI_Put(3), MPI_Get(3), MPI_Win_create(3),
85 MPI_Win_start(3), MPI_Win_complete(3), MPI_Accumulate(3),
86 MPI_Win_free(3), MPI_Win_get_group(3), MPI_Win_get_group(3),
87 MPI_Win_wait(3)
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91 For more information, please see the official MPI Forum web site, which
92 contains the text of both the MPI-1 and MPI-2 standards. These docu‐
93 ments contain detailed information about each MPI function (most of
94 which is not duplicated in these man pages).
95 http://www.mpi-forum.org/
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99 wfence.c
100LAM/MPI 7.1.2 2/23/2006 MPI_Win_fence(3)