Ok I'm gonna start doing that. I'm still having problems with my data thats passed through arg though. For instance when I try to access the size of my vector with the size function its size is 15418846 when I know its zero. Does anyone know what would cause this? And how do I know if I need to use a mutex. ex_thread doesn't use one but ex_thread2 does. I'm passing a vector returned from a get function into my struct thats being passed into the second thread. I don't have to lock the mutex in the main thread for when I use the data because it's just a copy of the data?

EDIT: crashing at mutex lock...