bionic (3) MPI_File_write_at_all_begin.openmpi.3.gz

NAME

       MPI_File_write_at_all_begin  -  Writes  a file at explicitly specified offsets; beginning part of a split
       collective routine (nonblocking).

SYNTAX

C Syntax

       #include <mpi.h> int MPI_File_write_at_all_begin(MPI_File fh, MPI_Offset offset,       const  void  *buf,
       int count, MPI_Datatype datatype)

Fortran Syntax (see FORTRAN 77 NOTES)

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

C++ Syntax

       #include <mpi.h>
       void MPI::File::Write_at_all_begin(MPI::Offset offset,
            const void* buf, int count,
            const MPI::Datatype& datatype)

INPUT/OUTPUT PARAMETER

       fh        File handle (handle).

INPUT PARAMETERS

       offset    File offset (handle).

       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

       MPI_File_write_at_all_begin  is  the beginning part of a split collective, that is, a nonblocking routine
       that attempts to write into the file associated with fh (at the offset position) a total number of  count
       data items having datatype type from the user's buffer buf.  The offset is in etype units relative to the
       current view. That is, holes are not counted when locating an offset. The  data  is  written  into  those
       parts of the file specified by the current view.

FORTRAN 77 NOTES

       The MPI standard prescribes portable Fortran syntax for the OFFSET argument only for Fortran 90.  FORTRAN
       77 users may use the non-portable syntax

            INTEGER*MPI_OFFSET_KIND OFFSET

       where MPI_OFFSET_KIND is a constant defined in mpif.h and gives the length of  the  declared  integer  in
       bytes.

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. 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.