- * - client_socket_ht: associate a client's socket (fd) to its "struct client"
- * This hash table owns the "struct client" which must thus be
- * disposed-of on removal from the hash table.
+ * - client_socket_ht: associate a client's socket (fd) to its
+ * "struct notification_client".
+ * This hash table owns the "struct notification_client" which must
+ * thus be disposed-of on removal from the hash table.
+ *
+ * - client_id_ht: associate a client's id to its "struct notification_client"
+ * This hash table holds a _weak_ reference to the
+ * "struct notification_client".