mpi_win_start(3openmpi) [osx man page]
MPI_Win_start(3OpenMPI) MPI_Win_start(3OpenMPI) NAME
MPI_Win_start - Starts an RMA access epoch for win SYNTAX
C Syntax #include <mpi.h> int MPI_Win_start(MPI_Group group, int assert, MPI_Win win) Fortran Syntax INCLUDE 'mpif.h' MPI_WIN_START(GROUP, ASSERT, WIN, IERROR) INTEGER GROUP, ASSERT, WIN, IERROR C++ Syntax #include <mpi.h> void MPI::Win::Start(const MPI::Group& group, int assert) const INPUT PARAMETERS
group The group of target processes (handle). assert Program assertion (integer). win Window object (handle). OUTPUT PARAMETERS
IERROR Fortran only: Error status (integer). DESCRIPTION
MPI_Win_start is a one-sided MPI communication synchronization call that starts an RMA access epoch for win. RMA calls issued on win during this epoch must access only windows at processes in group. Each process in group must issue a matching call to MPI_Win_post. MPI_Win_start is allowed to block until the corresponding MPI_Win_post calls have been executed, but is not required to. The assert argument is used to provide assertions on the context of the call that may be used for various optimizations. (See Section 6.4.4 of the MPI-2 Standard.) A value of assert = 0 is always valid. The following assertion value is supported: MPI_MODE_NOCHECK When this value is passed in to this call, the library assumes that the post call on the target has been called and it is not necessary for the library to check to see if such a call has been made. 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++ func- tions 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_Win_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_Win_post MPI_Win_complete Open MPI 1.2 March 2007 MPI_Win_start(3OpenMPI)
Check Out this Related Man Page
MPI_Win_post(3) MPI MPI_Win_post(3) NAME
MPI_Win_post - Start an RMA exposure epoch SYNOPSIS
int MPI_Win_post(MPI_Group group, int assert, MPI_Win win) INPUT PARAMETERS
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 opera- tion. 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 5/20/2010 MPI_Win_post(3)