1 /* if_en.h 4.3 81/12/03 */ 2 3 /* 4 * Structure of a Ethernet header. 5 */ 6 struct en_header { 7 u_char en_shost; 8 u_char en_dhost; 9 u_short en_type; 10 }; 11 12 #define ENPUP_PUPTYPE 0x0400 /* PUP protocol */ 13 #define ENPUP_IPTYPE 0x0800 /* IP protocol */ 14 15 /* 16 * The ENPUP_NTRAILER packet types starting at ENPUP_TRAIL have 17 * (type-ENPUP_TRAIL)*512 bytes of data followed 18 * by a PUP type (as given above) and then the (variable-length) header. 19 */ 20 #define ENPUP_TRAIL 0x1000 /* Trailer PUP */ 21 #define ENPUP_NTRAILER 16 22