t.Error("internal.poll.SendFile called with unexpected FD")
	}
}

func TestSendfile(t *testing.T) {
	ln := newLocalListener(t, "tcp")
	defer ln.Close()

	errc := make(chan error, 1)
	go func(ln Listener) {
		// Wait for a connection.
		conn, err := ln.Accept()
		if err != nil {
			errc <- err
			close(errc)
			return
		}

		go func() {
			defer close(errc)

}

func (ln *TCPListener) ok() bool { return ln != nil && ln.fd != nil && ln.fd.ctl != nil }

func (ln *TCPListener) accept() (*TCPConn, error) {
	fd, err := ln.fd.acceptPlan9()
	if err != nil {
		return nil, err
	}
	return newTCPConn(fd, ln.lc.KeepAlive, ln.lc.KeepAliveConfig, testPreHookSetKeepAlive, testHookSetKeepAlive), nil
}

func (ln *TCPListener) close() error {

	return
}

// FileListener returns a copy of the network listener corresponding
// to the open file f.
// It is the caller's responsibility to close ln when finished.
// Closing ln does not affect f, and closing f does not affect ln.
func FileListener(f *os.File) (ln Listener, err error) {
	ln, err = fileListener(f)
	if err != nil {
		err = &OpError{Op: "file", Net: "file+net", Source: nil, Addr: fileAddr(f.Name()), Err: err}
	}
	return
}

	}
	return err == syscall.EADDRNOTAVAIL
}

func (ln *TCPListener) ok() bool { return ln != nil && ln.fd != nil }

func (ln *TCPListener) accept() (*TCPConn, error) {
	fd, err := ln.fd.accept()
	if err != nil {
		return nil, err
	}
	return newTCPConn(fd, ln.lc.KeepAlive, ln.lc.KeepAliveConfig, testPreHookSetKeepAlive, testHookSetKeepAlive), nil
}

func (ln *TCPListener) close() error {
	return ln.fd.Close()
}

		t.Skipf("not supported on %s", runtime.GOOS)
	}

	ln, err := Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	defer ln.Close()
	var server Conn
	errc := make(chan error, 1)
	go func() {
		var err error
		server, err = ln.Accept()
		errc <- err
	}()
	client, err := Dial("tcp", ln.Addr().String())
	if err != nil {
		t.Fatal(err)
	}
	defer client.Close()

			ipBind = "tcp4"
		}
	}
	ln, err := tls.Listen(ipBind, net.JoinHostPort(ip, strconv.Itoa(port)), cfg)
	if err != nil {
		return nil, 0, err
	}
	port = ln.Addr().(*net.TCPAddr).Port
	return ln, port, nil
}

func listenOnUDS(uds string) (net.Listener, error) {
	_ = os.Remove(uds)
	ln, err := net.Listen("unix", uds)
	if err != nil {
		return nil, err
	}

	return ln, nil
}

	case "plan9":
		t.Skipf("not supported on %s", runtime.GOOS)
	}

	ln := newLocalListener(t, "tcp")
	defer ln.Close()

	if err := ln.(*TCPListener).SetDeadline(noDeadline); err != nil {
		t.Error(err)
	}
	if err := ln.(*TCPListener).SetDeadline(time.Now().Add(10 * time.Millisecond)); err != nil {
		t.Error(err)
	}
	c, err := ln.Accept()
	if err == nil {
		c.Close()
	}

	}

	t.Run("TCP", func(t *testing.T) {
		ln := newLocalListener(t, "tcp")
		defer ln.Close()

		cc1, err := ln.(*TCPListener).SyscallConn()
		if err != nil {
			t.Fatal(err)
		}
		if err := controlRawConn(cc1, ln.Addr()); err != nil {
			t.Fatal(err)
		}

		c, err := Dial(ln.Addr().Network(), ln.Addr().String())
		if err != nil {
			t.Fatal(err)
		}
		defer c.Close()

				t.Skipf("network %s is not testable on the current platform", network)
			}
			t.Parallel()

			ln := newLocalListener(t, network)
			switch network {
			case "unix", "unixpacket":
				defer os.Remove(ln.Addr().String())
			}
			defer ln.Close()

			c, err := Dial(ln.Addr().Network(), ln.Addr().String())
			if err != nil {
				t.Fatal(err)
			}
			switch network {
			case "unix", "unixpacket":

	if err != nil {
		t.Fatal(err)
	}
	ln, err := ListenTCP("tcp4", la)
	if err != nil {
		t.Fatal(err)
	}
	defer ln.Close()
	ln.Addr()
	mustSetDeadline(t, ln.SetDeadline, 30*time.Nanosecond)

	if c, err := ln.Accept(); err != nil {
		if !err.(Error).Timeout() {
			t.Fatal(err)
		}
	} else {
		c.Close()
	}
	if c, err := ln.AcceptTCP(); err != nil {
		if !err.(Error).Timeout() {