+/* 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 */
+int sd_peer_get_session(int fd, char **session);
+
+/* Similar to sd_pid_get_owner_uid(), but retrieves data about the peer of
+ * a connected AF_UNIX socket */
+int sd_peer_get_owner_uid(int fd, uid_t *uid);
+
+/* Similar to sd_pid_get_unit(), but retrieves data about the peer of
+ * a connected AF_UNIX socket */
+int sd_peer_get_unit(int fd, char **unit);
+
+/* Similar to sd_pid_get_user_unit(), but retrieves data about the peer of
+ * a connected AF_UNIX socket */
+int sd_peer_get_user_unit(int fd, char **unit);
+
+/* Similar to sd_pid_get_slice(), but retrieves data about the peer of
+ * a connected AF_UNIX socket */
+int sd_peer_get_slice(int fd, char **slice);