override fun write(
      source: Buffer,
      byteCount: Long,
    ) {
      check(!closed) { "closed" }
      if (byteCount == 0L) return

      with(socket.sink) {
        writeHexadecimalUnsignedLong(byteCount)
        writeUtf8("\r\n")
        write(source, byteCount)
        writeUtf8("\r\n")
      }
    }

    @Synchronized
    override fun flush() {