Monitoring CPU and disk utilization of a single program

How can I calculate CPU and disk utilization of another concurrent program? I.e. one program is running and开发者_开发技巧 other calculates the first's resource use.

I'm using C and C++ and running under Windows XP.

---

It is possible, as Process Explorer can do it, but I think you will have to use some kind of undocumented Windows API. PSAPI comes somewhat close, but it gives you only the memory usage information, not CPU or disk utilization.