title: C++ tellg() return type
body: <p>I have a large binary file that I am reading and I would like to compare the current position with an unsigned long long int. However, based on the C++ documentation, it isn't clear to me if:</p>
  
  <ol>
  <li>What is the return type of tellg()</li>
  <li>How can I compare tellg() with the unsigned long long int?</li>
  <li>Is it possible that the return type of tellg() has a maximum value (from numeric_limits) that is smaller than an unsigned long long int?</li>
  </ol>
  
  <p>Any answers or suggestions would be greatly appreciated.</p>