+
+ //! is the queue empty?
+ bool empty_p() const { return msg_queue.empty(); }
+
+ //| Acquires and release the mutex
+ void insert_tail(pmt::pmt_t msg);
+
+ /*!
+ * \returns returns pmt at head of queue or pmt_t() if empty.
+ */
+ pmt::pmt_t delete_head_nowait();
+
+ /*!
+ * \returns returns pmt at head of queue or pmt_t() if empty.
+ * Caller must already be holding the mutex
+ */
+ pmt::pmt_t delete_head_nowait_already_holding_mutex();