+BT_HIDDEN
+bt_bool bt_ctf_trace_has_clock_class(struct bt_ctf_trace *trace,
+ struct bt_ctf_clock_class *clock_class);
+
+/**
+@brief User function type to use with bt_ctf_trace_add_listener().
+
+@param[in] obj New CTF IR object which is part of the trace
+ class hierarchy.
+@param[in] data User data.
+
+@prenotnull{obj}
+*/
+typedef void (*bt_ctf_listener_cb)(struct bt_ctf_object *obj, void *data);
+
+/**
+@brief Adds the trace class modification listener \p listener to
+ the CTF IR trace class \p trace_class.
+
+Once you add \p listener to \p trace_class, whenever \p trace_class
+is modified, \p listener is called with the new element and with
+\p data (user data).
+
+@param[in] trace_class Trace class to which to add \p listener.
+@param[in] listener Modification listener function.
+@param[in] data User data.
+@returns 0 on success, or a negative value on error.
+
+@prenotnull{trace_class}
+@prenotnull{listener}
+@postrefcountsame{trace_class}
+*/
+BT_HIDDEN
+int bt_ctf_trace_add_listener(struct bt_ctf_trace *trace_class,
+ bt_ctf_listener_cb listener, void *data);
+
+/*
+ * bt_ctf_trace_get_metadata_string: get metadata string.
+ *
+ * Get the trace's TSDL metadata. The caller assumes the ownership of the
+ * returned string.
+ *
+ * @param trace Trace instance.
+ *
+ * Returns the metadata string on success, NULL on error.
+ */
+BT_HIDDEN
+char *bt_ctf_trace_get_metadata_string(struct bt_ctf_trace *trace);
+