// copying data directly between the two; there is no internal
// buffering.
func Pipe() (Conn, Conn) {
	cb1 := make(chan []byte)
	cb2 := make(chan []byte)
	cn1 := make(chan int)
	cn2 := make(chan int)
	done1 := make(chan struct{})
	done2 := make(chan struct{})

	p1 := &pipe{
		rdRx: cb1, rdTx: cn1,
		wrTx: cb2, wrRx: cn2,
		localDone: done1, remoteDone: done2,
		readDeadline:  makePipeDeadline(),