bsd man page for fdatasync

FDATASYNC(3P)						     POSIX Programmer's Manual						     FDATASYNC(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

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  indi-
       cate 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 Technol-
       ogy -- 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 .

IEEE
/The Open Group						       2003							     FDATASYNC(3P)