code: public String[] getHardLinkedFiles(String src) throws IOException {
      checkOpen();
      try {
        return namenode.getHardLinkedFiles(src);
      } catch (RemoteException re) {
        throw re.unwrapRemoteException(AccessControlException.class,
            NSQuotaExceededException.class, DSQuotaExceededException.class);
      }
    }
docs: See {@link ClientProtocol#getHardLinkedFiles(String)}.