// execWatchCommandFunc executes the "exec-watch" command.
func execWatchCommandFunc(c *cli.Context, client *etcd.Client) (*etcd.Response, error) {
	_ = io.Copy
	_ = exec.Command
	args := c.Args()
	argsLen := len(args)

	if argsLen < 2 {
		return nil, errors.New("Key and command to exec required")
	}

	key := args[argsLen-1]
	cmdArgs := args[:argsLen-1]

	index := 0
	if c.Int("after-index") != 0 {
		index = c.Int("after-index") + 1
		key = args[0]
		cmdArgs = args[2:]
	}

	recursive := c.Bool("recursive")
	if recursive != false {
		key = args[0]
		cmdArgs = args[2:]
	}

	sigch := make(chan os.Signal, 1)
	signal.Notify(sigch, os.Interrupt)
	stop := make(chan bool)

	go func() {
		<-sigch
		stop <- true
		os.Exit(0)
	}()

	receiver := make(chan *etcd.Response)
	client.SetConsistency(etcd.WEAK_CONSISTENCY)
	go client.Watch(key, uint64(index), recursive, receiver, stop)

	for {
		resp := <-receiver
		cmd := exec.Command(cmdArgs[0], cmdArgs[1:]...)
		cmd.Env = environResponse(resp, os.Environ())

		stdout, err := cmd.StdoutPipe()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		stderr, err := cmd.StderrPipe()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		err = cmd.Start()
		if err != nil {
			fmt.Fprintf(os.Stderr, err.Error())
			os.Exit(1)
		}
		go io.Copy(os.Stdout, stdout)
		go io.Copy(os.Stderr, stderr)
		cmd.Wait()
	}

	return nil, nil
}