1 /* 2 * Copyright (c) 1984, 1985, 1986, 1987 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)sp.h 7.4 (Berkeley) 06/28/90 8 */ 9 10 /* 11 * Definitions for Xerox NS style sequenced packet protocol 12 */ 13 14 struct sphdr { 15 u_char sp_cc; /* connection control */ 16 u_char sp_dt; /* datastream type */ 17 #define SP_SP 0x80 /* system packet */ 18 #define SP_SA 0x40 /* send acknowledgement */ 19 #define SP_OB 0x20 /* attention (out of band data) */ 20 #define SP_EM 0x10 /* end of message */ 21 u_short sp_sid; /* source connection identifier */ 22 u_short sp_did; /* destination connection identifier */ 23 u_short sp_seq; /* sequence number */ 24 u_short sp_ack; /* acknowledge number */ 25 u_short sp_alo; /* allocation number */ 26 }; 27