Try to acquire a lock.
If a lock cannot be acquired immediately, returns
false and leaves the
semaphore in its previous state.
true is returned iff the number of available locks is greater
Leonid Kramer, Sönke Ludwig, Manuel Frischknecht
© 2012-2015 RejectedSoftware e.K.
Subject to the terms of the MIT license, as written in the included LICENSE.txt file.