// Copy back all but what we're truncating.
    fullBuffer.read(bytesOut, lastFrame.start + length)
    outFrames.add(OutFrame(lastFrame.sequence, lastFrame.start, true))
    return writer
  }

  fun takeFrame(): InFrame = inFrames.take()

  fun play() {
    check(serverSocket == null)
    serverSocket = ServerSocket()
    serverSocket!!.reuseAddress = false
    serverSocket!!.bind(InetSocketAddress("localhost", 0), 1)