How to know number of user threads from /proc

Hi, I'm running a multithreaded program in OpenMP on linux to study CPU overloading. As the subject says, I need to know the number of threads this program creates (assuming in this case, number of threads in this program is same as the number of user threads) from the information kernel provides. I'm looking something similar to run-queue length from "sar -q 0" that gives me exact picture of number of user threads. From the implementation of sar, I found that this information is fetched from /proc filesystem. So is there anyway that /proc fs gives me the number of threads running in the system, apart from /proc/cpuinfo that gives me a static information of existing CPUs. -- Thanks, Kris