这真的不行，因为它不处理iOS加载和启动你的应用程序。

That really won't work because it doesn't deal with iOS loading and launching your app.

你应该做的***的事情是在 main 中记录一个时间戳>但同样，这将不包括iOS加载和启动应用程序到调用 main 的时间。

The best you should do is log a timestamp in main but again, this won't include the time it takes iOS to load and launch the app to the point that main is called.

你所做的任何时间都将从那一点开始，根据你的目标，这可能仍然有用。

Any timing you do will be from that point forward which may still be useful depending on your goal.