if n != 0 || err != io.EOF {
					t.Errorf("got (%d, %v); want (0, io.EOF)", n, err)
					return
				}
				switch c := c.(type) {
				case *TCPConn:
					err = c.CloseWrite()
				case *UnixConn:
					err = c.CloseWrite()
				}
				if err != nil {
					if perr := parseCloseError(err, true); perr != nil {
						t.Error(perr)
					}
					t.Error(err)
					return
				}

	}
	return nil
}

// CloseWrite shuts down the writing side of the Unix domain connection.
// Most callers should just use Close.
func (c *UnixConn) CloseWrite() error {
	if !c.ok() {
		return syscall.EINVAL
	}
	if err := c.fd.closeWrite(); err != nil {
		return &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}

			return fmt.Errorf("Read data = %q; want nothing", data)
		}

		if err := srv.CloseWrite(); err != nil {
			return fmt.Errorf("server CloseWrite: %v", err)
		}

		// Wait for clientCloseWrite to finish, so we know we
		// tested the CloseWrite before we defer the
		// sconn.Close above, which would also cause the
		// client to unblock like CloseWrite.
		<-clientDoneChan
		return nil
	}

	}

	return err
}

func (ffd *fakeNetFD) closeRead() error {
	return ffd.queue.closeRead()
}

func (ffd *fakeNetFD) closeWrite() error {
	if ffd.peer == nil {
		return os.NewSyscallError("closeWrite", syscall.ENOTCONN)
	}
	return ffd.peer.queue.closeWrite()
}

func (ffd *fakeNetFD) accept(laddr Addr) (*netFD, error) {
	if ffd.incoming == nil {

	}
	return nil
}

// CloseWrite shuts down the writing side of the TCP connection.
// Most callers should just use Close.
func (c *TCPConn) CloseWrite() error {
	if !c.ok() {
		return syscall.EINVAL
	}
	if err := c.fd.closeWrite(); err != nil {
		return &OpError{Op: "close", Net: c.fd.net, Source: c.fd.laddr, Addr: c.fd.raddr, Err: err}
	}

	// if needed.
	rstAvoidanceDelay = 1 * time.Nanosecond
}

// SetRSTAvoidanceDelay sets how long we are willing to wait between calling
// CloseWrite on a connection and fully closing the connection.
func SetRSTAvoidanceDelay(t *testing.T, d time.Duration) {
	prevDelay := rstAvoidanceDelay
	t.Cleanup(func() {
		rstAvoidanceDelay = prevDelay
	})

	return alertErr
}

var errEarlyCloseWrite = errors.New("tls: CloseWrite called before handshake complete")

// CloseWrite shuts down the writing side of the connection. It should only be
// called once the handshake has completed and does not call CloseWrite on the
// underlying connection. Most callers should just use [Conn.Close].
func (c *Conn) CloseWrite() error {
	if !c.isHandshakeComplete.Load() {

	conn, err := net.Dial("tcp", ts.Listener.Addr().String())
	if err != nil {
		t.Fatalf("Dial: %v", err)
	}
	err = conn.(*net.TCPConn).CloseWrite()
	if err != nil {
		t.Fatalf("CloseWrite: %v", err)
	}

	bs, err := io.ReadAll(conn)
	if err != nil {
		t.Errorf("ReadAll: %v", err)
	}
	got := string(bs)
	if got != "" {

//
// TODO(bcmills): This should arguably be a server configuration parameter,
// not a hard-coded value.
var rstAvoidanceDelay = 500 * time.Millisecond

type closeWriter interface {
	CloseWrite() error
}

var _ closeWriter = (*net.TCPConn)(nil)

// closeWriteAndWait flushes any outstanding data and sends a FIN packet (if
// client is connected via TCP), signaling that we're done. We then

`TryRead` and `TryWrite` are still available for non-blocking reads and writes.

To signify the end of the stream, close the ring buffer from the writer side with `rb.CloseWriter()`

Either side can use `rb.CloseWithError(err error)` to signal an error and close the ring buffer. 
Any reads or writes will return the error on next call.