zhongge · August 29, 2015 14:11
diff --git a/gistfile1.txt b/gistfile1.txt
 1. What is difference between atomic and nonatomic properties?
  One of the primary challenges of multi-threaded programming.
  Atomic properties are necessary in a reference counted multi threaded environment in order to stop objects from disappearing before a thread has a chance to retain them.
  In nonatomic, no such guarantees are made. Thus, nonatomic is considerably faster than "atomic".
 2. Which is default for synthesized properties?
  It is nonatomic.
  With "atomic", the synthesized setter/getter will ensure that a whole value is always returned from the getter or set by the setter, regardless of setter activity on any other thread.
 3. When would you use one vs. the others?
  I have used the "atomic" for multi-threading. In general, i have used the nonatomic property.
	1. What is difference between atomic and nonatomic properties?
	One of the primary challenges of multi-threaded programming.
	Atomic properties are necessary in a reference counted multi threaded environment in order to stop objects from disappearing before a thread has a chance to retain them.
	In nonatomic, no such guarantees are made. Thus, nonatomic is considerably faster than "atomic".
	2. Which is default for synthesized properties?
	It is nonatomic.
	With "atomic", the synthesized setter/getter will ensure that a whole value is always returned from the getter or set by the setter, regardless of setter activity on any other thread.
	3. When would you use one vs. the others?
	I have used the "atomic" for multi-threading. In general, i have used the nonatomic property.