How to setup an hourly CRON with a Must-Use Plugin?

So I know how to schedule a CRON event:

function setup_cron() {
    if (! wp_next_scheduled ( 'my_hourly_event' )) {
	wp_schedule_event(time(), 'hourly', 'my_hourly_event');
    }
}

add_action('my_hourly_event', 'do_this_hourly');

function do_this_hourly() {
	// do something every hour
}

And usually you would run this on plugin activation to avoid scheduling an event every time WordPress is initialized:

register_activation_hook(__FILE__, 'setup_cron');

But how would I setup this same type of CRON in a Must-Use plugin, which of course never fires an activation hook? How can I setup an hourly CRON once without a new event being scheduled every time my site is loaded?

Thank you!

• This topic was modified 8 years, 1 month ago by CoBu1.