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MPI_File_write_ordered_begin(3) man page (version 5.0.0rc2)

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Name

C]MPI_File_write_ordered_beginR] - Writes a file at a location specified by a shared file pointer; beginning part of a split collective routine (nonblocking).

Syntax

C Syntax



C]#include <mpi.h>int MPI_File_write_ordered_begin(MPI_File fh, const void *buf, int count, MPI_Datatype datatype)R]Fortran Syntax



C]USE MPI! or the older form: INCLUDE [aq]mpif.h[aq]MPI_FILE_WRITE_ORDERED_BEGIN(FH, BUF, COUNT, DATATYPE, IERROR) <type> BUF(*) INTEGER FH, COUNT, DATATYPE, IERRORR]Fortran 2008 Syntax



C]USE mpi_f08MPI_File_write_ordered_begin(fh, buf, count, datatype, ierror) TYPE(MPI_File), INTENT(IN) :: fh TYPE(*), DIMENSION(..), INTENT(IN), ASYNCHRONOUS :: buf INTEGER, INTENT(IN) :: count TYPE(MPI_Datatype), INTENT(IN) :: datatype INTEGER, OPTIONAL, INTENT(OUT) :: ierrorR]Input/Output Parameter

[bu]
C]fhR] : File handle (handle).

Input Parameters

[bu]
C]bufR] : Initial address of buffer (choice).
[bu]
C]countR] : Number of elements in buffer (integer).
[bu]
C]datatypeR] : Data type of each buffer element (handle).

Output Parameter

[bu]
C]IERRORR] : Fortran only: Error status (integer).

Description

C]MPI_File_write_ordered_beginR] is the beginning part of a split collective, nonblocking routine that must be called by all processes in the communicator group associated with the file handle C]fhR]. Each process may pass different argument values for the C]datatypeR] and C]countR] arguments. After all processes of the group have issued their respective calls, each process attempts to write, into the file associated with C]fhR], a total number of C]countR] data items having C]datatypeR] type contained in the user[cq]s buffer C]bufR]. 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.

Notes

All the nonblocking collective routines for data access are [lq]split[rq] into two routines, each with _begin or _end as a suffix. These split collective routines are subject to the semantic rules described in Section 9.4.5 of the MPI-2 standard.

Errors

Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument.

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 C]MPI_ERRORS_RETURNR]. The error handler may be changed with C]MPI_File_set_errhandlerR]; the predefined error handler C]MPI_ERRORS_ARE_FATALR] may be used to make I/O errors fatal. Note that MPI does not guarantee that an MPI program can continue past an error.


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