NAME

       MPI_File_iwrite  - Writes a file starting at the location specified by the individual file
       pointer (nonblocking, noncollective).

SYNTAX

C Syntax

       #include  <mpi.h>  int  MPI_File_iwrite(MPI_File  fh,  const   void   *buf,   int   count,
            MPI_Datatype datatype, MPI_Request *request)

Fortran Syntax

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

C++ Syntax

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

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

       request   Request object (handle).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_File_iwrite  is  a nonblocking version of the MPI_File_write interface. It 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.  MPI_File_iwrite stores the number of datatype elements actually written in
       status.  All other fields of status are undefined.

       It is erroneous to call this function if MPI_MODE_SEQUENTIAL mode was specified  when  the
       file was open.

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.