110     pub(crate) close_tx: Arc<Mutex<Option<mpsc::Sender<()>>>>,  field
126             close_tx: Arc::new(Mutex::new(None)),  in new()
139             let mut close = self.close_tx.lock().await;  in start()
144             let (close_tx, close_rx) = mpsc::channel(1);  in start()
145             *close = Some(close_tx);  in start()
151         let close_tx = Arc::clone(&self.close_tx);  in start()  localVariable
181                             let mut close = close_tx.lock().await;  in start()
196         let mut close_tx = self.close_tx.lock().await;  in stop()  localVariable
197         close_tx.take();  in stop()
203         let close_tx = self.close_tx.lock().await;  in is_running()  localVariable
204         close_tx.is_some()  in is_running()