title: In ObjectiveC, are pointers that are class instance variables initialised to 'nil', or otherwise?
body: <p>I.e., does ObjectiveC behave like C, in that if you create a pointer eg:</p>
  
  <pre><code>NSString* c;
  </code></pre>
  
  <p>Does c point to nil, or to the random value in the memory area that was reserved for it? </p>
  
  <p>In other words, do pointers get pre-initialized, or do I need to do that myself?  As I said, I'm aware this is not the case in C/C++, but I'm wondering if there's some ObjC magic here or not.</p>