+/*
+ * Apply a filter expression to an event.
+ *
+ * If event_name is NULL, the filter is applied to all events of the channel.
+ * If channel_name is NULL, a lookup of the event's channel is done.
+ * If both are NULL, the filter is applied to all events of all channels.
+ */
+extern int lttng_set_event_filter(struct lttng_handle *handle,
+ const char *event_name,
+ const char *channel_name,
+ const char *filter_expression);