struct icmp_rdp_head {
  u_char type;
  u_char code;
  u_short cksum;
  union {
    u_char unused[4];
    struct addy { 
      u_char number_of_addrs;
      u_char addr_entry_size;
      u_short lifetime;
    } a;
  } u;
};

struct icmp_rdp_advert {
  u_long ira_addr;
  u_long ira_preference;
};

struct values {
  u_long sourceaddr;
  u_long destaddr;
  u_long routeraddr;
  u_long routeraddr2;
  int lifetime;
  int delay;
  int num_pkts;
  int id;
  int pref;
  int verbose;
};

#define ETHER 0
#define NO_ETHER 1

#define ICMP_ROUTERADVERT 9