MAXTTL
opack_ip->ip_ttl = ttl ? ttl : MAXTTL;
ip->ip_ttl = MAXTTL;
if (optval > 0 && optval <= MAXTTL)
error = ip_getoptval(sopt, &imo->imo_multicast_ttl, MAXTTL);
ip->ip_ttl = in4p_ip(inp).ip_ttl ? in4p_ip(inp).ip_ttl : MAXTTL;
iph_out->ip_ttl = MAXTTL;
iph_out->ip_ttl = MAXTTL;
out->ip_ttl = MAXTTL;
ip->ip_ttl = MAXTTL; /* applies to unicasts only */