void lttng_ust_context_set_event_notifier_group_provider(const char *name,
size_t (*get_size)(void *priv, size_t offset),
void (*record)(void *priv,
void lttng_ust_context_set_event_notifier_group_provider(const char *name,
size_t (*get_size)(void *priv, size_t offset),
void (*record)(void *priv,