title: PHP CURL: The usage of the @filename API for file uploading is deprecated
body: <p>I got this message:</p>
  
  <pre><code>Deprecated: curl_setopt_array(): The usage of the @filename API for file uploading is deprecated. Please use the CURLFile class instead
  </code></pre>
  
  <p><strong>I know</strong> that I may rewrite my code using <code>CURLFile</code> class, but it's awailable only from 5.5.</p>
  
  <p>My site <strong>must</strong> run on PHP 5.3, PHP 5.4 or PHP 5.5, so I can't drop 5.3 and 5.4 compatibility. So I  can't use CURLFile.</p>
  
  <p>How can I rewrite code to make it run on any PHP without any PHP version checks?</p>