My school has an apache/mysql server that we make and host websites from as projects. I am doing an ebay type site where people bid on a product until time runs out. Problem is I don't know how to trigger that the product should be delisted and the buyer and seller notified that the auction is over. mysql trigger updates only work when a mysql action like select, insert delete, etc are triggered, I'm not sure about php (If my website would get more traffic then simply me editing and maintaining it, I would simply run a php script every time the index page is accessed. But I might do that anyway.) and honestly, I think this might be impossible without higher access privileges. I would like to note I have access to the GCC compiler, and can confirm I can compile program (just not installing programs for obvious reasons).
I'm currently skimming through: http://www.netzmafia.de/skripten/unix/linux-daemon-howto.html to see if this is possible in my position.