IN6P_HOPLIMIT
#define IN6P_CONTROLOPTS (IN6P_PKTINFO|IN6P_HOPLIMIT|IN6P_HOPOPTS|\
if (inp->inp_flags & IN6P_HOPLIMIT) {
OPTSET(IN6P_HOPLIMIT);
OPTSET2292(IN6P_HOPLIMIT);
optval = OPTBIT(IN6P_HOPLIMIT);
optval = OPTBIT(IN6P_HOPLIMIT);