+/*
+ * NOTE: initialize num_known_controls to 1 so that cid = 0 always
+ * addresses an undefined control; this allows to safely test for
+ * well known controls even if they are not registered, e.g. if
+ * they get moved to modules. An example is sc_LDAPsync, which
+ * is implemented in the syncprov overlay and thus, if configured
+ * as dynamic module, may not be registered. One side effect is that
+ * slap_known_controls[0] == NULL, so it should always be used
+ * starting from 1.
+ * FIXME: should we define the "undefined control" oid?
+ */