llchdr_xid
struct llchdr_xid *xid;
msgether->ether_type = htons(sizeof (struct llchdr_xid) +
xid = (struct llchdr_xid *)(msgllc + 1);
nmp->b_wptr += sizeof (struct llchdr_xid);
sizeof (struct llchdr_xid), BPRI_MED);