获取的是开机后WIFI,3G/GPRS网络下使用流量

iOS获取设备流量使用情况，iPhone Data Usage Tracking/Monitoring，获取的是开机后WIFI,3G/GPRS网络下使用流量(仅仅只能获取开机后的)。

#include <arpa/inet.h> 
#include <net/if.h> 
#include <ifaddrs.h> 
#include <net/if_dl.h> 
  
+ (NSArray *)getDataCounters 
{ 
    BOOL   success; 
    struct ifaddrs *addrs; 
    const struct ifaddrs *cursor; 
    const struct if_data *networkStatisc;  
   
    int WiFiSent = 0; 
    int WiFiReceived = 0; 
    int WWANSent = 0; 
    int WWANReceived = 0; 
   
    NSString *name=[[[NSString alloc]init]autorelease]; 
   
    success = getifaddrs(&addrs;) == 0; 
    if (success)  
    { 
        cursor = addrs; 
        while (cursor != NULL)  
        { 
            name=[NSString stringWithFormat:@"%s",cursor->ifa_name]; 
            NSLog(@"ifa_name %s == %@\n", cursor->ifa_name,name); 
            // names of interfaces: en0 is WiFi ,pdp_ip0 is WWAN  
            if (cursor->ifa_addr->sa_family == AF_LINK)  
            { 
                if ([name hasPrefix:@"en"])  
                { 
                    networkStatisc = (const struct if_data *) cursor->ifa_data; 
                    WiFiSent+=networkStatisc->ifi_obytes; 
                    WiFiReceived+=networkStatisc->ifi_ibytes; 
                    NSLog(@"WiFiSent %d ==%d",WiFiSent,networkStatisc->ifi_obytes); 
                    NSLog(@"WiFiReceived %d ==%d",WiFiReceived,networkStatisc->ifi_ibytes); 
                } 
                if ([name hasPrefix:@"pdp_ip"])  
                { 
                    networkStatisc = (const struct if_data *) cursor->ifa_data; 
                    WWANSent+=networkStatisc->ifi_obytes; 
                    WWANReceived+=networkStatisc->ifi_ibytes; 
                    NSLog(@"WWANSent %d ==%d",WWANSent,networkStatisc->ifi_obytes); 
                    NSLog(@"WWANReceived %d ==%d",WWANReceived,networkStatisc->ifi_ibytes); 
                }  
            } 
            cursor = cursor->ifa_next; 
        } 
        freeifaddrs(addrs); 
    }        
    return [NSArray arrayWithObjects:[NSNumber numberWithInt:WiFiSent], 
         [NSNumber numberWithInt:WiFiReceived], 
         [NSNumber numberWithInt:WWANSent], 
         [NSNumber numberWithInt:WWANReceived], nil]; 
}