     }
 
     OSSpinLockUnlock(&lock)
-    return true
+    return sent
   }
 
   /**


    if closed && head >= tail
    {
      OSSpinLockUnlock(&lock)
      return nil
    }

    OSSpinLockLock(&lock)
    closed = true

    // Unblock waiting threads.
    if !readerQueue.isEmpty, let rs = readerQueue.dequeue()
    {
      dispatch_semaphore_signal(rs)
    }
    else if !writerQueue.isEmpty, let ws = writerQueue.dequeue()
    {
      dispatch_semaphore_signal(ws)
    }
    OSSpinLockUnlock(&lock)
  }
