* If event_name is NULL, all events are enabled with that filter.
* If channel_name is NULL, the default channel is used (channel0) and created
* if not found.
+ * If filter_expression is NULL, an event without associated filter is
+ * created.
*/
extern int lttng_enable_event_with_filter(struct lttng_handle *handle,
struct lttng_event *event, const char *channel_name,