382 struct mscp {  struct
383 	u_short mscp_msglen;		/* length in bytes */  argument
384 	u_char	mscp_msgtc;		/* type (high 4 bits) and credits */  argument
385 	u_char	mscp_vcid;		/* virtual circuit ID */  argument
386 	long	mscp_cmdref;		/* command reference number */  argument
387 	u_short mscp_unit;		/* unit number */  argument
388 	u_short mscp_seqnum;		/* sequence number */  argument
389 	u_char	mscp_opcode;		/* opcode */  argument
391 	u_char	mscp_flags;		/* flags */  argument
392 	u_short mscp_modifier;		/* modifier (commands) */  argument
403 	} mscp_un;  argument
404 /*???*/ long	mscp_xxx;		/* pad to 64 bytes */  argument
411 #define MSCP_MSGLEN	(sizeof (struct mscp) - 4)  argument