title: Check if a pointer points to a valid structure
body: <p>I have N statically allocated structures.</p>
  
  <pre><code>struct exemple{
       ...
  }
  
  struct exemple array[N];
  struct exemple *test_ptr = 0x3; /* random address */
  </code></pre>
  
  <p>Can I check if test_prt points to a valid address? i.e. it points to one "struct example" allocated.</p>