* @param f1name name of first file
     * @param f2 second file to compare
     * @return comparison result for sorting
     * @throws IOException if an I/O error occurs
     */
    protected int compareNames(final SmbFile f1, final String f1name, final SmbFile f2) throws IOException {
        if (f1.isDirectory() != f2.isDirectory()) {
            return f1.isDirectory() ? -1 : 1;
        }