wordpress-simple-cronjobs.php

<?
add_action('wp', 'myplugin_schedule_cron');
add_action('myplugin_cronjob', 'myplugin_cron_function');
#add_action('wp_head', 'myplugin_cron_function'); //test

/*-------------------------------------------------------------
Name: myplugin_schedule_cron

Purpose: schedule cron on page load if not scheduled
Receive: - none -
Return: - none -
-------------------------------------------------------------*/
function myplugin_schedule_cron() {
  if ( !wp_next_scheduled( 'myplugin_cronjob' ) )
    wp_schedule_event(time(), 'daily', 'myplugin_cronjob');
}

/*-------------------------------------------------------------
Name: myplugin_cron_function

Purpose: function to run with cron
Receive: - none -
Return: - none -
-------------------------------------------------------------*/
function myplugin_cron_function() {
  //do something
}