Is NSUserDefault thread safe?
arrays, objective-c, thread-safety
Solution
The Apple iOS 5.1 and OS X 10.7 documentation say that it is thread-safe; therefore it is thread-safe.
Problem
https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSUserDefaults_Class/Reference/Reference.html says it is ...should prevent users from editing that preference by disabling any appropriate controls. The NSUserDefaults class is thread-safe. Persistence of NSURL and file reference URLs... This long discussion says it isn't http://www.cocoabuilder.com/archive/cocoa/155227-nsuserdefaults-thread-safety.html So which one is right? Also why the difference of opinion.