MPI_Win_test(3)                     1.4.1""                    MPI_Win_test(3)



NAME
       MPI_Win_test - Attempts to complete an RMA exposure epoch; a
       nonblocking version of MPI_Win_wait


SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Win_test(MPI_Win win, int *flag)


Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_WIN_TEST( WIN, FLAG, IERROR)
            INTEGER  WIN, IERROR


C++ Syntax
       #include <mpi.h>
       bool MPI::Win::Test() const


INPUT PARAMETERS
       win       Window object (handle)



OUTPUT PARAMETERS
       IERROR    Fortran only: Error status (integer).

       flag      The returning state of the test for epoch closure.



DESCRIPTION
       MPI_Win_test is a one-sided MPI communication synchronization call, a
       nonblocking version of MPI_Win_wait. It returns ag = true if
       MPI_Win_wait would return, ag = false otherwise. The effect of return
       of MPI_Win_test with flag = true is the same as the effect of a return
       of MPI_Win_wait. If ag = false is returned, then the call has no
       visible effect.

       Invoke MPI_Win_test only where MPI_Win_wait can be invoked. Once the
       call has returned ag = true, it must not be invoked anew, until the
       window is posted anew.



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++
       functions 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_wait




                                 Jan 14, 2010                  MPI_Win_test(3)
