How to know if a function is finished?

I'm using

[NSTimer scheduledTimerWithTimeInterval:0 target:self selector:@selector(myfunc:) userInfo:text repeats:false];

in my code. How can I know if myfunc has finished running开发者_运维问答 so that I can fetch the global variables it has changed?

Thank you!

---

You can notify the caller via Cocoa's notification system.