title: How to verify if a void pointer (void *) is one of two data types?
body: <p>I am writing a function where i would like to accept 2 <code>type</code>s of parameters.</p>
  
  <ul>
  <li>A <code>string</code> (char *)</li>
  <li>A <code>structure</code> where there will be n number of elements.</li>
  </ul>
  
  <p>And to achieve this i am thinking of using a simple <code>void *</code> as parameter type. But i do not know how to verify if the parameter is one type or the other, safely.</p>