title: PHP DirectoryIterator::getSize - how real size and size on disk?
body: <p>I'm using code like this on windows XAMPP server.</p>
  
  <pre><code>    $di = new RecursiveDirectoryIterator($dir);
      $files = new RecursiveIteratorIterator(
          $di,
          RecursiveIteratorIterator::LEAVES_ONLY
      );
      $totalsize = 0;
      foreach($files as $a =&gt; $b) {
          $totalsize += $b-&gt;getSize();
      }
  </code></pre>
  
  <p>Size i get is same (0.1MB difference) as Size On Disk == 62MB
  However, windows shows real size is 42MB</p>
  
  <p>Is there a way to get "real size"? Also, is real size and size on disk different on linux partition types also?</p>