index.php

<?php
/**
 * @package    Joomla.Site
 *
 * @copyright  Copyright (C) 2005 - 2018 Open Source Matters, Inc. All rights reserved.
 * @license    GNU General Public License version 2 or later; see LICENSE.txt
 */

/**
 * NOTE: This file should remain compatible with PHP 5.2 to allow us to run our PHP minimum check and show a friendly error message
 */

/**
 * Define the application's minimum supported PHP version as a constant so it can be referenced within the application.
 */
define('JOOMLA_MINIMUM_PHP', '7.0');

if (version_compare(PHP_VERSION, JOOMLA_MINIMUM_PHP, '<'))
{
	die(
		str_replace(
			'{{PHP_VERSION}}',
			JOOMLA_MINIMUM_PHP,
			file_get_contents(dirname(__FILE__) . '/templates/system/incompatible.html')
		)
	);
}

/**
 * Constant that is checked in included files to prevent direct access.
 * define() is used rather than "const" to not error for PHP 5.2 and lower
 */
define('_JEXEC', 1);

// Run the application - All executable code should be triggered through this file
require_once dirname(__FILE__) . '/includes/app.php';