103 строки
3.1 KiB
Plaintext
103 строки
3.1 KiB
Plaintext
.\" Copyright 2010 Cisco Systems, Inc. All rights reserved.
|
|
.\" Copyright 2006-2008 Sun Microsystems, Inc.
|
|
.\" Copyright (c) 1996 Thinking Machines Corporation
|
|
.TH MPI_File_seek_shared 3 "#OMPI_DATE#" "#PACKAGE_VERSION#" "#PACKAGE_NAME#"
|
|
.SH NAME
|
|
\fBMPI_File_seek_shared\fP \- Updates the global shared file pointer (collective).
|
|
|
|
.SH SYNTAX
|
|
.ft R
|
|
.nf
|
|
C Syntax
|
|
#include <mpi.h>
|
|
int MPI_File_seek_shared(MPI_File \fIfh\fP, MPI_Offset \fIoffset\fP,
|
|
int \fIwhence\fP)
|
|
|
|
Fortran Syntax (see FORTRAN 77 NOTES)
|
|
INCLUDE 'mpif.h'
|
|
MPI_FILE_SEEK_SHARED(\fIFH\fP,\fI OFFSET\fP,\fI WHENCE\fP,\fI IERROR\fP)
|
|
INTEGER \fIFH, WHENCE, IERROR\fP
|
|
INTEGER(KIND=MPI_OFFSET_KIND) \fIOFFSET\fP
|
|
|
|
.fi
|
|
.SH C++ Syntax
|
|
.nf
|
|
#include <mpi.h>
|
|
void MPI::File::Seek_shared(MPI::Offset \fIoffset\fP, int \fIwhence\fP)
|
|
|
|
.fi
|
|
.SH INPUT PARAMETERS
|
|
.ft R
|
|
.TP 1i
|
|
fh
|
|
File handle (handle).
|
|
.TP 1i
|
|
offset
|
|
File offset (integer).
|
|
.TP 1i
|
|
whence
|
|
Update mode (integer).
|
|
|
|
.SH OUTPUT PARAMETER
|
|
.ft R
|
|
.TP 1i
|
|
IERROR
|
|
Fortran only: Error status (integer).
|
|
|
|
.SH DESCRIPTION
|
|
.ft R
|
|
MPI_File_seek_shared updates the shared file pointer according to
|
|
.I whence,
|
|
which could have the following possible values:
|
|
.TP
|
|
o
|
|
MPI_SEEK_SET - The pointer is set to
|
|
.I offset.
|
|
.TP
|
|
o
|
|
MPI_SEEK_CUR - The pointer is set to the current pointer position plus
|
|
.I offset.
|
|
.TP
|
|
o
|
|
MPI_SEEK_END - The pointer is set to the end of the file plus
|
|
.I offset.
|
|
.sp
|
|
.RE
|
|
MPI_File_seek_shared is collective; all the processes in the communicator
|
|
group associated with the file handle
|
|
.I fh
|
|
must call MPI_File_seek_shared with the same
|
|
.I offset
|
|
and
|
|
.I whence.
|
|
All processes in the communicator group are synchronized before the shared file pointer is updated.
|
|
|
|
.sp
|
|
The
|
|
.I 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.
|
|
|
|
.SH FORTRAN 77 NOTES
|
|
.ft R
|
|
The MPI standard prescribes portable Fortran syntax for
|
|
the \fIOFFSET\fP argument only for Fortran 90. FORTRAN 77
|
|
users may use the non-portable syntax
|
|
.sp
|
|
.nf
|
|
INTEGER*MPI_OFFSET_KIND \fIOFFSET\fP
|
|
.fi
|
|
.sp
|
|
where MPI_OFFSET_KIND is a constant defined in mpif.h
|
|
and gives the length of the declared integer in bytes.
|
|
|
|
.SH 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.
|
|
.sp
|
|
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.
|
|
|