I know the topic is a bit fuzzy. Let me explain.
I've made a plugin I would like to do some clean-up every hour, and I would like to do that, not using wp-cron, but a real cron. With a simple curl calling a page.
But if I simply make a an action, like the others in my plug-in, then curl needs to be logged in to reach that action. It could be done, but I know there is another way. The XML-sitemap by Arne Brachold can do this, but I can't figure out how. There is so much about WordPress I don't know ;)
Can anybody enlighten me? Its a tough question to search for.