1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <math.h> 4 #include <string.h> 5 #include <unistd.h> 6 #include <sys/ioctl.h> 7 #include <sys/types.h> 8 #include <sys/sysctl.h> 9 #include <sys/socket.h>10 #include <netinet/in.h>11 #include <netdb.h>12 #include <arpa/inet.h>13 #include <sys/sockio.h>14 #include <net/if.h>15 #include <net/ethernet.h>16 #include <errno.h>17 #include <net/if_dl.h>18 #include <ifaddrs.h>19 #include <mach/machine.h>

 1 + (NSString *)getIPAddress 2 { 3     NSString *address = @"error"; 4     struct ifaddrs *interfaces = NULL; 5     struct ifaddrs *temp_addr = NULL; 6     int success = 0; 7     // retrieve the current interfaces - returns 0 on success 8     success = getifaddrs(&interfaces); 9     if (success == 0)10     {11         // Loop through linked list of interfaces12         temp_addr = interfaces;13         while(temp_addr != NULL)14         {15             if(temp_addr->ifa_addr->sa_family == AF_INET)16             {17                 // Check if interface is en0 which is the wifi connection on the iPhone18                 if([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"])19                 {20                     // Get NSString from C String21                     address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];22                 }23             }24             temp_addr = temp_addr->ifa_next;25         }26     }27     // Free memory28     freeifaddrs(interfaces);29     return address;30 }