int myqtt_async_queue_waiters ( MyQttAsyncQueue queue)

Allows to get current waiting threads on the provided queue.

queueThe queue that is being used to request the number of waiting threads.
The number of waiting threads or -1 if it fails. The only way to make the function to fail is to provide a null queue reference.

References myqtt_mutex_lock(), and myqtt_mutex_unlock().

Referenced by myqtt_listener_unlock(), and myqtt_thread_pool_stats().