source: trunk/www.guidonia.net/wp/wp-cron.php@ 44

<?php
/**
 * WordPress Cron Implementation for hosts, which do not offer CRON or for which
 * the user has not setup a CRON job pointing to this file.
 *
 * The HTTP request to this file will not slow down the visitor who happens to
 * visit when the cron job is needed to run.
 *
 * @package WordPress
 */

ignore_user_abort(true);

if ( !empty($_POST) || defined('DOING_AJAX') || defined('DOING_CRON') )
        die();

/**
 * Tell WordPress we are doing the CRON task.
 *
 * @var bool
 */
define('DOING_CRON', true);

if ( !defined('ABSPATH') ) {
        /** Setup WordPress environment */
        require_once('./wp-load.php');
}

if ( false === $crons = _get_cron_array() )
        die();

$keys = array_keys( $crons );
$local_time = time();

if ( isset($keys[0]) && $keys[0] > $local_time )
        die();

foreach ($crons as $timestamp  => $cronhooks) {
        if ( $timestamp > $local_time )
                break;

        foreach ($cronhooks as $hook => $keys) {

                foreach ($keys as $k => $v) {

                        $schedule = $v['schedule'];

                        if ($schedule != false) {
                                $new_args = array($timestamp, $schedule, $hook, $v['args']);
                                call_user_func_array('wp_reschedule_event', $new_args);
                        }

                        wp_unschedule_event($timestamp, $hook, $v['args']);

                        do_action_ref_array($hook, $v['args']);
                }
        }
}

die();