How do I know if was require_once?
<p>I have two files</p>

<p><strong>1 - index.php
  2 - main.php</strong></p>

<p><strong>index.php</strong> call to <strong>main.php</strong> by <code>&lt;?php require_once("../../includes/main.php"); ?&gt;</code></p>

<p>How do I know from <strong>main.php</strong> when it Execute,</p>

<p>if <strong>index.php</strong> call to him or same user Execute it Standalone?<br>
what I should ask inside main php to continue run the program if was require_once ?
Thx</p>
