How to detect if a file is being included or directly ran

Question

I have a php file that I include in my php script, but I don\'t want people to be able to directly run the file(without being included). How can I prevent that from happenin

Answer 1

I use a sentinel constant, defined in the "including" script, and the "included" script looks for it.

Example:

/* main.php */
define('SENTINEL', 1);
include "included.inc.php"

/* included.inc.php */
if (!defined('SENTINEL')) die("Wanted to be smart?? Nice try.");