bionic (3) MPI_Win_start.3.gz

NAME

       MPI_Win_start -  Start an RMA access epoch for MPI

SYNOPSIS

       int MPI_Win_start(MPI_Group group, int assert, MPI_Win win)

INPUT PARAMETERS

       group  - group of target 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_start operation.  The value zero is always correct.  Other assertion  values  may
       be or'ed together.  Assertions tha are valid for MPI_Win_start are:

       MPI_MODE_NOCHECK
              -  the matching calls to MPI_WIN_POST have already completed on all target processes when the call
              to MPI_WIN_START is made.  The nocheck option can be specified in a start call if and only  if  it
              is  specified  in  each matching post call. This is similar to the optimization of ready-send that
              may save a handshake when the handshake is implicit in the code. (However, ready-send  is  matched
              by a regular receive, whereas both start and post must specify the nocheck option.)

THREAD AND INTERRUPT SAFETY

       This routine is thread-safe.  This means that this routine may be safely used by multiple threads without
       the need for any user-provided thread locks.  However, the routine is  not  interrupt  safe.   Typically,
       this  is  due to the use of memory allocation routines such as malloc or other non-MPICH runtime routines
       that are themselves not interrupt-safe.

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.
       MPI_ERR_WIN
              - Invalid MPI window object
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information about this error code.

                                                   11/12/2016                                   MPI_Win_start(3)