.. _mpi_file_write_all_begin:


MPI_File_write_all_begin
========================

.. include_body

:ref:`MPI_File_write_all_begin` - Writes a file starting at the locations
specified by individual file pointers; beginning part of a split
collective routine (nonblocking).


SYNTAX
------



C Syntax
^^^^^^^^

.. code-block:: c

   #include <mpi.h>

   int MPI_File_write_all_begin(MPI_File fh, const void *buf,
   	int count, MPI_Datatype datatype)


Fortran Syntax
^^^^^^^^^^^^^^

.. code-block:: fortran

   USE MPI
   ! or the older form: INCLUDE 'mpif.h'
   MPI_FILE_WRITE_ALL_BEGIN(FH, BUF, COUNT, DATATYPE, IERROR)
   	<type>	BUF(*)
   	INTEGER	FH, COUNT, DATATYPE, IERROR


Fortran 2008 Syntax
^^^^^^^^^^^^^^^^^^^

.. code-block:: fortran

   USE mpi_f08
   MPI_File_write_all_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) :: ierror


INPUT/OUTPUT PARAMETER
----------------------
* ``fh``: File handle (handle).

INPUT PARAMETERS
----------------
* ``buf``: Initial address of buffer (choice).
* ``count``: Number of elements in buffer (integer).
* ``datatype``: Data type of each buffer element (handle).

OUTPUT PARAMETER
----------------
* ``IERROR``: Fortran only: Error status (integer).

DESCRIPTION
-----------

:ref:`MPI_File_write_all_begin` is the beginning part of a split collective,
nonblocking routine that attempts to write into the file associated with
*fh* (at the current individual file pointer position maintained by the
system) a total number of *count* data items having *datatype* type from
the user's buffer *buf.* The data is written into those parts of the
file specified by the current view.


NOTES
-----

All the nonblocking collective routines for data access are "split" 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
MPI_ERRORS_RETURN. The error handler may be changed with
:ref:`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.
