}
		t.Fatal(err)
	}
	defer ti.teardown()

	time.Sleep(3 * time.Millisecond)

	// If Listen fails (on Linux with “bind: invalid argument”), zoneCache was
	// not updated when encountering a nonexistent interface:
	ln, err := Listen("tcp", "[fe80::1%"+ti.name+"]:0")
	if err != nil {
		t.Fatal(err)
	}
	ln.Close()
	if err := ti.teardown(); err != nil {
		t.Fatal(err)

	if err := os.Remove(s.path); err != nil && !os.IsNotExist(err) {
		return fmt.Errorf("failed to remove (%v): %v", s.path, err)
	}

	l, err := net.Listen("unix", s.path)
	if err != nil {
		return fmt.Errorf("listen error (%v): %v", s.path, err)
	}
	defer l.Close()

	srv := http.Server{Handler: s.mux}
	go func() {
		<-stopCh
		srv.Close()
	}()
	return srv.Serve(l)

}

func createListenerOnFreePort() (net.Listener, int, error) {
	ln, err := net.Listen("tcp", ":0")
	if err != nil {
		return nil, 0, err
	}

	// get port
	tcpAddr, ok := ln.Addr().(*net.TCPAddr)
	if !ok {
		ln.Close()
		return nil, 0, fmt.Errorf("invalid listen address: %q", ln.Addr().String())
	}

	return ln, tcpAddr.Port, nil

		l, err := net.Listen("tcp", host)
		if err == nil {
			l.Close()
			break
		}
		port++
	}

	subProcess := exec.Command("go", "run", "./testdata/tcpecho.go")

	subProcess.Env = append(os.Environ(), "GOOS=wasip1", "GOARCH=wasm")

	switch os.Getenv("GOWASIRUNTIME") {
	case "wazero":
		subProcess.Env = append(subProcess.Env, "GOWASIRUNTIMEARGS=--listen="+host)
	case "wasmtime", "":

// limitations under the License.

package hbone

import (
	"net"
	"testing"
	"time"
)

func newTCPServer(t testing.TB, data string) string {
	n, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	t.Logf("opened listener on %v", n.Addr().String())
	go func() {
		for {
			c, err := n.Accept()
			if err != nil {
				log.Info(err)
				return

				return nil, nil
			},
			MinVersion: tls.VersionTLS12,
		}
		// Listen on the given port and update the port if it changed from what was passed in.
		listener, port, err = listenOnAddressTLS(c.ListenerIP, c.Port.Port, config)
		// Store the actual listening port back to the argument.
		c.Port.Port = port
	} else {
		// Listen on the given port and update the port if it changed from what was passed in.

			laddr = nil
		}
		if raddr != nil && raddr.isWildcard() {
			raddr = nil
		}
		if raddr == nil && (sotype != syscall.SOCK_DGRAM || laddr == nil) {
			return nil, errMissingAddress
		}
	case "listen":
	default:
		return nil, errors.New("unknown mode: " + mode)
	}

	fd, err := socket(ctx, net, syscall.AF_UNIX, sotype, 0, false, laddr, raddr, ctxCtrlFn)
	if err != nil {
		return nil, err
	}
	return fd, nil

	done := make(chan error)
	go blockingSyscall(50*time.Millisecond, done)
	if err := <-done; err != nil {
		log.Fatal(err)
	}

	// checkNetworkUnblock relies on this.
	ln, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		log.Fatalf("listen failed: %v", err)
	}
	defer ln.Close()
	go func() {
		c, err := ln.Accept()
		if err != nil {
			return
		}
		time.Sleep(time.Millisecond)
		var buf [1]byte

		timerDone := make(chan bool)
		go func() {
			time.Sleep(time.Millisecond)
			timerDone <- true
		}()
		<-timerDone

		// A bit of network.
		ln, err := net.Listen("tcp", "127.0.0.1:0")
		if err != nil {
			log.Fatalf("listen failed: %v", err)
			return
		}
		defer ln.Close()
		go func() {
			c, err := ln.Accept()
			if err != nil {
				return
			}
			time.Sleep(time.Millisecond)

	listenCfg := net.ListenConfig{
		Control: setTCPParametersFn(opts),
	}

	for i, serverAddr := range serverAddrs {
		l, e := listenCfg.Listen(ctx, "tcp", serverAddr)
		if e != nil {
			if opts.Trace != nil {
				opts.Trace(fmt.Sprint("listenCfg.Listen: ", e))
			}

			listenErrs[i] = e
			continue
		}

		if opts.Trace != nil {
			opts.Trace(fmt.Sprint("adding listener to ", l.Addr()))