+ (NSString *)getIPAddress:(BOOL)preferIPv4

{
    NSArray *searchArray = preferIPv4 ?
@[ IOS_VPN @"/" IP_ADDR_IPv4, IOS_VPN @"/" IP_ADDR_IPv6, IOS_WIFI @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6, IOS_CELLULAR @"/" IP_ADDR_IPv4, IOS_CELLULAR @"/" IP_ADDR_IPv6 ] :
@[ IOS_VPN @"/" IP_ADDR_IPv6, IOS_VPN @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6, IOS_WIFI @"/" IP_ADDR_IPv4, IOS_CELLULAR @"/" IP_ADDR_IPv6, IOS_CELLULAR @"/" IP_ADDR_IPv4 ] ;

  NSDictionary *addresses = [self getIPAddresses];
  //    NSLog(@"addresses: %@", addresses);

  __block NSString *address;
 [searchArray enumerateObjectsUsingBlock:^(NSString *key, NSUInteger idx, BOOL *stop)
 {
     address = addresses[key];
     if(address) *stop = YES;

   } ];

   return address ? address : @"0.0.0.0";
}


  + (NSDictionary *)getIPAddresses
  {

     NSMutableDictionary *addresses = [NSMutableDictionary dictionaryWithCapacity:8];

     struct ifaddrs *interfaces;
     if(!getifaddrs(&interfaces)) {

     struct ifaddrs *interface;
     for(interface=interfaces; interface; interface=interface->ifa_next) {
        
            if(!(interface->ifa_flags & IFF_UP) /* || (interface->ifa_flags & IFF_LOOPBACK) */ ) {
            continue; // deeply nested code harder to read
      }

      const struct sockaddr_in *addr = (const struct sockaddr_in*)interface->ifa_addr;
        char addrBuf[ MAX(INET_ADDRSTRLEN, INET6_ADDRSTRLEN) ];
       
     if(addr && (addr->sin_family==AF_INET || addr->sin_family==AF_INET6)) {
           
      NSString *name = [NSString stringWithUTF8String:interface->ifa_name];
            NSString *type;
            if(addr->sin_family == AF_INET) {
                if(inet_ntop(AF_INET, &addr->sin_addr, addrBuf, INET_ADDRSTRLEN)) {
                    type = IP_ADDR_IPv4;
                }
            } else {
                const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6*)interface->ifa_addr;
                if(inet_ntop(AF_INET6, &addr6->sin6_addr, addrBuf, INET6_ADDRSTRLEN)) {
                    type = IP_ADDR_IPv6;
                }
            }
            if(type) {
                NSString *key = [NSString stringWithFormat:@"%@/%@", name, type];
                addresses[key] = [NSString stringWithUTF8String:addrBuf];
            }
         }
      }
        freeifaddrs(interfaces);
    }
    return [addresses count] ? addresses : nil;
}