NAME
fdatasync - synchronize the data of a file (REALTIME)
SYNOPSIS
#include <unistd.h>
int fdatasync(int fildes);
DESCRIPTION
The fdatasync() function shall force all currently queued I/O
operations associated with the file indicated by file descriptor fildes
to the synchronized I/O completion state.
The functionality shall be equivalent to fsync() with the symbol
_POSIX_SYNCHRONIZED_IO defined, with the exception that all I/O
operations shall be completed as defined for synchronized I/O data
integrity completion.
RETURN VALUE
If successful, the fdatasync() function shall return the value 0;
otherwise, the function shall return the value -1 and set errno to
indicate the error. If the fdatasync() function fails, outstanding I/O
operations are not guaranteed to have been completed.
ERRORS
The fdatasync() function shall fail if:
EBADF The fildes argument is not a valid file descriptor open for
writing.
EINVAL This implementation does not support synchronized I/O for this
file.
In the event that any of the queued I/O operations fail, fdatasync()
shall return the error conditions defined for read() and write().
The following sections are informative.
EXAMPLES
None.
APPLICATION USAGE
None.
RATIONALE
None.
FUTURE DIRECTIONS
None.
SEE ALSO
aio_fsync() , fcntl() , fsync() , open() , read() , write() , the Base
Definitions volume of IEEE Std 1003.1-2001, <unistd.h>
COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online
at http://www.opengroup.org/unix/online.html .