How to lock a method when using multithreading?

Question

how can I stop 2nd thread to access same method that is being used by first thread?

score 2 · Accepted Answer · answered Aug 25 '12 at 12:25

2

One option is to use @synchronized in the method.

- (NSString *)someMethod {
  @synchronized(self) {
      // do some work
  }
}

It allows the method to be called but will synchronize on itself and protect it's work (and more importantly the data it's working on).

answered Aug 25 '12 at 12:25

bryanmac

It worked. Thank you. I still have a doubt. Once the process is completed by first thread, does the 2nd thread have access to this method automatically? Do all other threads wait until first thread completes it work? – Dee Aug 25 '12 at 12:32
Yes, both threads enter the method, one executes the synchronized block of code and when it does the other will continue execution. – bryanmac Aug 25 '12 at 13:20
Here's a deeper explanation on what it does: http://stackoverflow.com/questions/1215330/how-does-synchronized-lock-unlock-in-objective-c – bryanmac Aug 25 '12 at 13:21

score 0 · Answer 2 · edited May 23 '17 at 12:15

0

Have a look at NSLock.

Just found it when looking for a C# lock statement, it appears to do the same thing..

There is also another SO thread relating to synchronisation:

edited May 23 '17 at 12:15

Community

answered Aug 25 '12 at 12:27

WraithNath

2 Answers2