support restarting only on file changes.

go/qst.go

}
var delay = flag.Duration("delay", 1*time.Second, "time to wait until restart")
var autoRestart = flag.Bool("autorestart", true, "restart after command exists")
func main() {
	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
		log.Fatalf("error: no mapping found for `%s'", file)
	}
	runner := MakeRunner(fn(file))
	runner := &Runner{nil, fn(file), false, *autoRestart}
	go runCmd(file, runner)
	c := make(chan os.Signal, 1)
	restart  bool
}
func MakeRunner(shellCmd string) *Runner {
	return &Runner{nil, shellCmd, false, true}
}
func (r *Runner) Start() error {
	if r.started {
		return errors.New("already started, use Restart()")
			time.Sleep(*delay)
			if !r.restart {
				r.started = false
				break
			}
		}
}
func (r *Runner) Restart() error {
	return r.Kill()
	if r.started {
		return r.Kill()
	} else {
		return r.Start()
	}
}
func (r *Runner) Stop() {