(void*)(opt + opt->len) <= (void*)(end); opt += opt->len)
-int ra_init(const char *ifname, const struct in6_addr *ifid, unsigned int options);
+int ra_init(const char *ifname, const struct in6_addr *ifid,
+ unsigned int options, unsigned int holdoff_interval);
bool ra_link_up(void);
bool ra_process(void);