17.2.146. MPI_File_write

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

17.2.146.1. SYNTAX

17.2.146.1.1. C Syntax

#include <mpi.h>

int MPI_File_write(MPI_File fh, const void *buf,
     int count, MPI_Datatype datatype,
     MPI_Status *status)

17.2.146.1.2. Fortran Syntax

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

17.2.146.1.3. Fortran 2008 Syntax

USE mpi_f08
MPI_File_write(fh, buf, count, datatype, status, ierror)
     TYPE(MPI_File), INTENT(IN) :: fh
     TYPE(*), DIMENSION(..), INTENT(IN) :: buf
     INTEGER, INTENT(IN) :: count
     TYPE(MPI_Datatype), INTENT(IN) :: datatype
     TYPE(MPI_Status) :: status
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

17.2.146.2. INPUT/OUTPUT PARAMETER

  • fh: File handle (handle).

17.2.146.3. INPUT PARAMETERS

  • buf: Initial address of buffer (choice).

  • count: Number of elements in buffer (integer).

  • datatype: Data type of each buffer element (handle).

17.2.146.4. OUTPUT PARAMETERS

  • status: Status object (status).

  • IERROR: Fortran only: Error status (integer).

17.2.146.5. DESCRIPTION

MPI_File_write 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_write 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 opened.

17.2.146.6. 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 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.