title: Write a 64-bit program in C
body: <p>This might be a very stupid question:</p>
  
  <ul>
  <li>How do I write a program especially for 64-bit architecture.</li>
  </ul>
  
  <p>We are working on a Solaris system.</p>
  
  <p>Is there any difference in the code itself for 32-bit and 64-bit?
  Or is it more a question of header-files?</p>
  
  <p>Can anybody give me a simple hello-username example for 64-bit?</p>