INTDEF (clntudp_create)
INTDEF (clntudp_bufcreate)
INTDEF (clntudp_create)static intis_network_up (int sock){  struct ifaddrs *ifa;  if (getifaddrs (&ifa) != 0)    return 0;  struct ifaddrs *run = ifa;  while (run != NULL)    {      if ((run->ifa_flags & IFF_UP) != 0	  && run->ifa_addr != NULL	  && run->ifa_addr->sa_family == AF_INET)	break;      run = run->ifa_next;    }  freeifaddrs (ifa);  return run != NULL;}