usr/src/sys/netns/idp.h

/*      idp.h     6.1     85/05/30     */

/*
 * Definitions for NS(tm) Internet Datagram Protocol
 */
struct idp {
        u_short idp_sum;        /* Checksum */
        u_short idp_len;        /* Length, in bytes, including header */
        u_char  idp_tc;         /* Transport Crontrol (i.e. hop count) */
        u_char  idp_pt;         /* Packet Type (i.e. level 2 protocol) */
        struct ns_addr  idp_dna;        /* Destination Network Address */
        struct ns_addr  idp_sna;        /* Source Network Address */
};