title: Can I assume the size of long int is always 4 bytes?
body: <p>Is it always true that <code>long int</code> (which as far as I understand is a synonym  for <code>long</code>) is <code>4</code> bytes?  </p>
  
  <p>Can I rely on that?  If not, could it be true for a POSIX based OS?</p>