--- File.delete(filename ... )
--- File.unlink(filename ... )

    եޤեο֤ޤ˼Ԥ
    㳰 Errno::EXXX ȯޤ

    Υ᥽åɤ̾եκѤǡǥ쥯ȥκˤ
    Dir.rmdir Ȥޤ

