'Retrieves the number of hard links to the file.
This count keeps track of how many directories have entries for this
file. If the count is ever decremented to zero then the file itself is
discarded as soon as no process still holds it open.  Symbolic links
are not counted in the total.
@raise NotImplementedError: if the platform is Windows, since Windows
doesn\'t maintain a link count for directories, and L{os.stat} does
not set C{st_nlink} on Windows anyway.
@return: the number of hard links to the file
@rtype: L{int}
@since: 11.0'

def getNumberOfHardLinks(self):

    if platform.isWindows():
        raise NotImplementedError
    st = self._statinfo
    if (not st):
        self.restat()
        st = self._statinfo
    return st.st_nlink
