ncprange_setip4
ncprange_setip4(&dest, host, GetIpAddr(arg->argv[arg->argn + 1]));
ncprange_setip4(&ipcp->cfg.my_range, host, ipcp->cfg.netmask);
ncprange_setip4(&ipcp->cfg.peer_range, ipcp->cfg.netmask, ipcp->cfg.netmask);
extern void ncprange_setip4(struct ncprange *, struct in_addr, struct in_addr);