MPI_File_write_ordered(3)          Open MPI          MPI_File_write_ordered(3)



NAME
       MPI_File_write_ordered - Writes a file at a location specified by a
       shared file pointer (blocking, collective).


SYNTAX
       C Syntax
           #include <mpi.h>
           int MPI_File_write_ordered(MPI_File fh, void *buf,
                         int count, MPI_Datatype datatype,
                         MPI_Status *status)

       Fortran Syntax
           INCLUDE 'mpif.h'
           MPI_FILE_WRITE_ORDERED(FH, BUF, COUNT, DATATYPE,
                         STATUS, IERROR)
                  <type>     BUF(*)
                  INTEGER    FH, COUNT, DATATYPE, STATUS(MPI_STATUS_SIZE), IERROR


C++ Syntax
       #include <mpi.h>
       void MPI::File::Write_ordered(const void* buf, int count,
            const MPI::Datatype& datatype, MPI::Status& status)

       void MPI::File::Write_ordered(const void* buf, int count,
            const MPI::Datatype& datatype)


INPUT PARAMETERS
       fh        File handle (handle).

       buf       Initial address of buffer (choice).

       count     Number of elements in buffer (integer).

       datatype  Data type of each buffer element (handle).


OUTPUT PARAMETERS
       status    Status object (Status).

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       MPI_File_write_ordered is a collective routine. This routine must be
       called by all processes in the communicator group associated with the
       file handle fh.  Each process may pass different argument values for
       the datatype and count arguments. Each process attempts to write, into
       the file associated with fh, a total number of count data items having
       datatype type contained in the user's buffer buf.  For each process,
       the location in the file at which data is written is the position at
       which the shared file pointer would be after all processes whose ranks
       within the group are less than that of this process had written their
       data. MPI_File_write_ordered returns the number of datatype elements
       written in status.  The shared file pointer is updated by the amounts
       of data requested by all processes of the group.


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. For MPI I/O function errors, the default error handler is set
       to MPI_ERRORS_RETURN. The error handler may be changed with
       MPI_File_set_errhandler; the predefined error handler
       MPI_ERRORS_ARE_FATAL may be used to make I/O errors fatal. Note that
       MPI does not guarantee that an MPI program can continue past an error.




1.4.1                            Jan 14, 2010        MPI_File_write_ordered(3)
