err = opt.Complete(new(pflag.FlagSet))
		if err != nil {
			t.Fatal(err)
		}
		opt.proxyServer = tc.proxyServer

		errCh := make(chan error, 1)
		go func() {
			errCh <- opt.runLoop(ctx)
		}()

		if tc.append {
			file.WriteString("append fake content")
		}

		select {
		case err := <-errCh:
			if err != nil {
				if !strings.Contains(err.Error(), tc.expectedErr) {

	if err != nil {
		return err
	}
	if o.InitAndExit {
		return nil
	}

	o.proxyServer = proxyServer
	return o.runLoop(ctx)
}

// runLoop will watch on the update change of the proxy server's configuration file.
// Return an error when updated
func (o *Options) runLoop(ctx context.Context) error {
	if o.watcher != nil {
		o.watcher.Run()
	}

	// run the proxy in goroutine
	go func() {

func (c *conn) setState(nc net.Conn, state ConnState, runHook bool) {
	srv := c.server
	switch state {
	case StateNew:
		srv.trackConn(c, true)
	case StateHijacked, StateClosed:
		srv.trackConn(c, false)
	}
	if state > 0xff || state < 0 {
		panic("internal error")
	}
	packedState := uint64(time.Now().Unix()<<8) | uint64(state)
	c.curState.Store(packedState)
	if !runHook {
		return
	}