def parse228(resp) # :nodoc:
      if resp[0, 3] != "228"
        raise FTPReplyError, resp
      end
      if m = /\(4,4,(?<host>\d+(,\d+){3}),2,(?<port>\d+,\d+)\)/.match(resp)
        return parse_pasv_ipv4_host(m["host"]), parse_pasv_port(m["port"])
      elsif m = /\(6,16,(?<host>\d+(,(\d+)){15}),2,(?<port>\d+,\d+)\)/.match(resp)
        return parse_pasv_ipv6_host(m["host"]), parse_pasv_port(m["port"])
      else
        raise FTPProtoError, resp
      end
      return host, port
    end
handler for response code 228
(Entering Long Passive Mode)

Returns host and port.