[Boost-users] [threads] How to test for running thread

Hi, Suppose I have a thread running, I issue an interrupt(), and the thread starts to perform its cleanup code. As this may take some time, I'd like to know when the thread actually is stopped. Is there some standard approach on how to do this? I was thinking about testing if the thread object equals Not-a-Thread, but I've yet to find out how... Thanks! Koen