iphoneip-addresslocal-network

Get IP address of the current Wi-Fi access point on a iPhone?


I am trying to connect from my iPhone to a socket server running on the same network on my computer. How can I get the local IP address of the computer that is running the socket server?


Solution

  • #include <netinet/in.h>
    #include <arpa/inet.h>
    #include <net/if.h>
    #include <ifaddrs.h>
    
    - (NSString *)getIPAddress
    {
        NSString *address = @"error";
        struct ifaddrs *interfaces = NULL;
        struct ifaddrs *temp_addr = NULL;
        int success = 0;
    
        // Retrieve the current interfaces - returns 0 on success
        success = getifaddrs(&interfaces);
        if (success == 0)
        {
            // Loop through linked list of interfaces
            temp_addr = interfaces;
            while(temp_addr != NULL)
            {
                if(temp_addr->ifa_addr->sa_family == AF_INET)
                {
                    // Check if interface is en0 which is the wifi connection on the iPhone
                    if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"])
                    {
                        // Get NSString from C String
                        address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];
                    }
                }
                temp_addr = temp_addr->ifa_next;
            }
        }
        // Free memory
        freeifaddrs(interfaces);
        return address;
    }