title: How to pause a scheduled selector?
body: <p>Is There is any way to pause a particular selector, like :</p>
  
  <pre><code>[self schedule:@selector(funcA:) interval:0.05];
  </code></pre>
  
  <p>is it possible to pause this scheduler and then resume.</p>
  
  <p>Another question: is there  any way to check whether a scheduler is running???</p>