mpi_file_seek_shared(3)
NAME
MPI_File_seek_shared - Updates the global shared file pointer (collective).
SYNTAX
- C Syntax
- #include <mpi.h>
int MPI_File_seek_shared(MPI_File fh, MPI_Offset offset,int whence) - Fortran Syntax (see FORTRAN 77 NOTES)
- INCLUDE 'mpif.h'
MPI_FILE_SEEK_SHARED(FH, OFFSET, WHENCE, IERROR)INTEGER FH, WHENCE, IERROR
INTEGER(KIND=MPI_OFFSET_KIND) OFFSET
C++ Syntax
#include <mpi.h>
void MPI::File::Seek_shared(MPI::Offset offset, int whence)
INPUT PARAMETERS
fh File handle (handle).
offset File offset (integer).
whence Update mode (integer).
OUTPUT PARAMETER
IERROR Fortran only: Error status (integer).
DESCRIPTION
- MPI_File_seek_shared updates the shared file pointer according to
whence, which could have the following possible values:
- o MPI_SEEK_SET - The pointer is set to offset.
- o MPI_SEEK_CUR - The pointer is set to the current pointer posi
tion plus offset.
- o MPI_SEEK_END - The pointer is set to the end of the file plus
offset.
- MPI_File_seek_shared is collective; all the processes in the communicator
- group associated with the file handle fh must call MPI_File_seek_shared with
- the same offset and whence. All processes in the communicator group are syn
- chronized before the shared file pointer is updated.
- The offset can be negative, which allows seeking backwards. It is erroneous to
- seek to a negative position in the view. The end of the view is defined to be
- the position of the next elementary data item, relative to the current view,
- following the last whole elementary data item accessible.
FORTRAN 77 NOTES
- The MPI standard prescribes portable Fortran syntax for the OFFSET
argument only for Fortran 90. FORTRAN 77 users may use the nonportable 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.
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.