How to get CPU temperature and fan speed on OS X?

Question

How do I get CPU temperature and fan speeds in OS X?

I understand that information is obtained from IOHWSensor in IOKit, but I'm unable to find any reliable information on how to exactly do that.

I've found an article with a sample program - http://www.booktou.com/node/148/0321278542/ch10lev1sec7.html, but all I get with it is the GPU temperature. I'm sure there are CPU temperature sensors on the unibody Macs, so that means I'm doing something wrong.

Answer 1

The source code for this Prefpane that's called FanControl is avilable; it shows temperatures and fan speeds: http://www.lobotomo.com/products/FanControl/index.html