PROLOG This manual page is part of the POSIX Programmer s Manual. The Linux implementation of this interface may differ (consult the corresponding 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 opera- tions 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 opera- tions shall be completed as defined for synchronized I/O data integrity completion.

RETURN VALUE If successful, the fdatasync() function shall return the value 0; oth- erwise, 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.





SEE ALSO aio_fsync(), fcntl(), fsync(), open(), read(), write(), the Base Defi- nitions 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 .

IEEE/The Open Group 2003 FDATASYNC(3P)