- * If the call is successful, then the filter string's address is put
- * in *filter_string. If the event has no filter string, *filter_string
- * is set to NULL. The caller does NOT own *filter_string.
+ * This creation function, introduced in LTTng 2.11, works around
+ * the fact that the layout of the 'lttng_event' is publicly exposed.
+ *
+ * It allocates a larger object which exposes the same public fields
+ * as a 'struct lttng_event', but also allows the use of the following extended
+ * attribute setters:
+ * - lttng_event_set_userspace_probe_location();
+ *
+ * Events created through this function must be destroyed using
+ * lttng_event_destroy().
+ *
+ * Returns a zeroed lttng_event on success, NULL on error.
+ */
+extern struct lttng_event *lttng_event_create(void);
+
+/*
+ * Destroy an lttng_event.
+ *
+ * This destruction function, introduced in LTTng 2.11, should only
+ * be used with events created by lttng_event_create().
+ */
+extern void lttng_event_destroy(struct lttng_event *event);
+
+/*
+ * Get the filter expression of a specific LTTng event.
+ *
+ * If the call is successful, then the filter expression's address is put
+ * in *filter_expression. If the event has no filter expression,
+ * *filter_expression is set to NULL. The caller does NOT own
+ * *filter_expression.