NAME¶
MPI_Win_post - Start an RMA exposure epoch
SYNOPSIS¶
int MPI_Win_post(MPI_Group group, int assert, MPI_Win win)
- group
- - group of origin processes (handle)
- assert
- - Used to optimize this call; zero may be used as a
default. See notes. (integer)
- win
- - window object (handle)
NOTES¶
The
assert argument is used to indicate special conditions for the fence
that an implementation may use to optimize the
MPI_Win_post operation.
The value zero is always correct. Other assertion values may be or'ed
together. Assertions that are valid for
MPI_Win_post are:
- MPI_MODE_NOCHECK
- - the matching calls to MPI_WIN_START have not yet
occurred on any origin processes when the call to MPI_WIN_POST is
made. The nocheck option can be specified by a post call if and only if it
is specified by each matching start call.
- MPI_MODE_NOSTORE
- - the local window was not updated by local stores (or
local get or receive calls) since last synchronization. This may avoid the
need for cache synchronization at the post call.
- MPI_MODE_NOPUT
- - the local window will not be updated by put or accumulate
calls after the post call, until the ensuing (wait) synchronization. This
may avoid the need for cache synchronization at the wait call.
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.
LOCATION¶
win_post.c