Multiple mice on OS X

Question

I am developing an OS X application that is supposed to take input from two mice. I want to read the motion of each mouse independently. What would be the best way to do this?

Answer 1

Unless you can force one of the mice to not be dealt with as a mouse, both will continue to control the pointer. However, you can use IOKit to write a custom USB HID driver to allow your app to read from one or both of the mice (although this would probably interfere with using them as normal mice). Building Customized User Client Drivers for USB Devices would be a good place to start for how to interact directly with USB mice.