def each_key(key, &block)
      index = 0
      subkey = nil

      subkey_max_len, _ = reg_query_info_key_max_lengths(key)

      begin
        subkey, filetime = reg_enum_key(key, index, subkey_max_len)
        yield subkey, filetime if !subkey.nil?
        index += 1
      end while !subkey.nil?

      index
    end
def each_key(key, &block)
      index = 0
      subkey = nil

      subkey_max_len, _ = reg_query_info_key_max_lengths(key)

      begin
        subkey, filetime = reg_enum_key(key, index, subkey_max_len)
        yield subkey, filetime if !subkey.nil?
        index += 1
      end while !subkey.nil?

      index
    end
subkey is String which contains name of subkey.
 wtime is last write time as FILETIME (64-bit integer). (see Registry.wtime2time)