I've just released version 0.7 of Toro. Toro provides semaphores, locks, events, conditions, and queues for Tornado coroutines. It enables advanced coordination among coroutines, similar to what you do in a multithreaded application. Get the latest version with "pip install --upgrade toro". Toro's documentation, with plenty of examples, is on ReadTheDocs.
There is one bugfix in this release. Semaphore.wait() is supposed to wait until the semaphore can be acquired again:
@gen.coroutine def coro(): sem = toro.Semaphore(1) assert not sem.locked() # A semaphore with initial value of 1 can be acquired once, # then it's locked. sem.acquire() assert sem.locked() # Wait for another coroutine to release the semaphore. yield sem.wait()
... however, there was a bug and the semaphore didn't mark itself "locked" when it was acquired, so "wait" always returned immediately. I'm grateful to "abing" on GitHub for noticing the bug and contributing a fix.