+
+const char *address_family_boolean_to_string(AddressFamilyBoolean b) _const_;
+AddressFamilyBoolean address_family_boolean_from_string(const char *s) _const_;
+
+int config_parse_address_family_boolean(const char *unit, const char *filename, unsigned line, const char *section, unsigned section_line, const char *lvalue, int ltype, const char *rvalue, void *data, void *userdata);
+
+/* Opeartional State */
+
+const char* link_operstate_to_string(LinkOperationalState s) _const_;
+LinkOperationalState link_operstate_from_string(const char *s) _pure_;