usr/src/sys/vax/if/if_en.h

/*
 * Copyright (c) 1982 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 *
 *      @(#)if_en.h     6.3 (Berkeley) %G%
 */

/*
 * Structure of a Ethernet header.
 */
struct  en_header {
        u_char  en_shost;
        u_char  en_dhost;
        u_short en_type;
};

#define ENTYPE_PUP      0x0200          /* PUP protocol */
#define ENTYPE_IP       0x0201          /* IP protocol */

/*
 * The ENTYPE_NTRAILER packet types starting at
 * ENTYPE_TRAIL have (type-ENTYPE_TRAIL)*512 bytes
 * of data followed by an Ethernet type (as given above)
 * and then the (variable-length) header.
 */
#define ENTYPE_TRAIL    0x1000          /* Trailer type */
#define ENTYPE_NTRAILER 16

#define EN_BROADCAST    0               /* Hardware broadcast address */