-extern size_t lttng_ust_list_apps(pid_t **pids);
-extern size_t lttng_list_sessions(struct lttng_session **sessions);
+extern int lttng_ust_list_apps(pid_t **pids);
+extern int lttng_list_sessions(struct lttng_session **sessions);
+extern int lttng_list_traces(uuid_t *uuid, struct lttng_trace **traces);
+extern void lttng_set_current_session_uuid(char *uuid);
+extern int lttng_ust_create_trace(pid_t pid);
+extern int lttng_ust_start_trace(pid_t pid);
+extern int lttng_ust_stop_trace(pid_t pid);