FDATASYNC(2)              NetBSD System Calls Manual              FDATASYNC(2)

NAME
     fdatasync -- synchronize the data of a file

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     int
     fdatasync(int fd);

DESCRIPTION
     The fdatasync() function forces all modified data associated with the
     file descriptor fd to be flushed to stable storage.

     The functionality is as described for fsync(2), with the exception that
     file status information need not be synchronized, which may result in a
     performance gain, compared to fsync(2).  This behaviour is commonly known
     as synchronized I/O data integrity completion.

RETURN VALUES
     A value of 0 is returned on success.  Otherwise, a value -1 is returned
     and errno is set to indicate the error.

ERRORS
     The fdatasync() function will fail if:

     [EBADF]            The fd argument is not a valid file descriptor open
                        for writing.

     [EINVAL]           This implementation does not support synchronized I/O
                        for this file.

     [ENOSYS]           The fdatasync() function is not supported by this
                        implementation.

     In the event that any of the I/O operations to be performed fail,
     fdatasync() returns the error conditions defined for read(2) and
     write(2), and outstanding I/O operations are not guaranteed to have been
     completed.

SEE ALSO
     fsync(2), open(2), read(2), write(2)

STANDARDS
     The fdatasync() function conforms to IEEE Std 1003.1b-1993 (``POSIX.1'').

NetBSD 5.0_STABLE              October 25, 2003              NetBSD 5.0_STABLE
