title: pathinfo() expects parameter 1 to be string array given codeigniter
body: <p>Here is my code</p>
  
  <pre><code>$filename = $_FILES[$file_element_name]['name'];
  
  $ext = pathinfo($filename, PATHINFO_EXTENSION);
  </code></pre>
  
  <p>Why this line throws an error </p>
  
  <blockquote>
    <p><code>pathinfo()</code> expects parameter 1 to be string array given</p>
  </blockquote>