Locks mutex. If mutex is already locked by another thread, the
current thread will block until mutex is unlocked by the other
thread. If mutex is already locked by the calling thread, this
functions increases the depth of mutex and returns immediately.
Locks mutex. If mutex is already locked by another thread, the current thread will block until mutex is unlocked by the other thread. If mutex is already locked by the calling thread, this functions increases the depth of mutex and returns immediately.