title: Using strtoul in C
body: <p>In C, why does</p>
  
  <p><code>strtoul(argv[1])</code></p>
  
  <p>just doesn't work? It looks like more parameters are needed but I can't prevent how long the number will be.</p>
  
  <p>Thanks!</p>
  
  <p>p.s. (argv[1] is properly setted).</p>