"testing"
)

func TestCreateListenerSharePort(t *testing.T) {
	c := net.ListenConfig{Control: permitPortReuse}

	l, port, err := CreateListener("tcp", "127.0.0.1:0", c)
	if err != nil {
		t.Fatalf("failed to create listener: %v", err)
	}
	defer l.Close()

	l2, _, err := CreateListener("tcp", fmt.Sprintf("127.0.0.1:%d", port), c)
	if err != nil {
		t.Fatalf("failed to create 2nd listener: %v", err)
	}
	defer l2.Close()
}

		Handler: http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
			w.WriteHeader(http.StatusOK)
		}),
		MaxHeaderBytes: 1 << 20,
		TLSConfig:      tlsConfig,
	}
	listener, _, err := createListener("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatal(err)
	}
	apiPort := listener.Addr().String()
	go func() {
		t.Logf("listening on %s", listener.Addr().String())