# File test/sockutils.rb, line 22
    def tcp_socketpair
      socket = TCPServer.open('localhost', 0)
      begin
        family, port, host, addr = socket.addr
        cli_sock = TCPSocket.open('localhost', port)
        svr_sock = socket.accept
        setsockopt(cli_sock)
        setsockopt(svr_sock)
        return cli_sock, svr_sock
      ensure
        socket.close if socket
      end
    end