-/* Similar to sd_pid_get_session(), but retrieves data about peer of
- * connected AF_UNIX socket */
+/* Get the control group from a PID, relative to the root of the
+ * hierarchy. */
+int sd_pid_get_cgroup(pid_t pid, char **cgroup);
+
+/* Similar to sd_pid_get_session(), but retrieves data about the peer
+ * of a connected AF_UNIX socket */