title: Determine size of dynamically allocated memory in C
body: <p>Is there a way in C to find out the size of dynamically allocated memory?     </p>
  
  <p>For example, after</p>
  
  <pre><code>char* p = malloc (100);
  </code></pre>
  
  <p>Is there a way to find out the size of memory associated with <code>p</code>?</p>