40 struct ip {  struct
42 	uchar_t	ip_hl:4,		/* header length */  argument
43 		ip_v:4;			/* version */  argument
48 	uchar_t	ip_tos;			/* type of service */  argument
49 	ushort_t ip_len;		/* total length */  argument
50 	ushort_t ip_id;			/* identification */  argument
51 	ushort_t ip_off;		/* fragment offset field */  argument
54 	uchar_t	ip_ttl;			/* time to live */  argument
55 	uchar_t	ip_p;			/* protocol */  argument
56 	ushort_t ip_sum;		/* checksum */  argument
57 	struct	in_addr ip_src, ip_dst;	/* source and dest address */  argument