在Mac OSX中获取网卡MAC地址

今天在CocoaChina上看到有人发帖在询问如何在Mac OSX下获得网卡的物理地址，恰好最近在学习IOKit的一些知识，所以通过IOKit的接口肯定是可以很方便的拿到MAC地址信息的，但不知道还有没有其它更方便的API了，所以我姑且贴出一段通过IOKit去获得网卡MAC地址的代码：

- (void)applicationDidFinishLaunching:(NSNotification *)aNotification
{
    kern_return_t kr;
    CFMutableDictionaryRef matchDict;
    io_iterator_t iterator;
    io_registry_entry_t entry;
    
    matchDict = IOServiceMatching("IOEthernetInterface");
    kr = IOServiceGetMatchingServices(kIOMasterPortDefault, matchDict, &iterator);
    
    NSDictionary *resultInfo = nil;
    
    while ((entry = IOIteratorNext(iterator)) != 0)
    {
        CFMutableDictionaryRef properties=NULL;
        kr = IORegistryEntryCreateCFProperties(entry,
                                               &properties,
                                               kCFAllocatorDefault,
                                               kNilOptions);
        if (properties)
        {
            resultInfo = (__bridge_transfer NSDictionary *)properties;
            NSString *bsdName = [resultInfo objectForKey:@"BSD Name"];
            NSData *macData = [resultInfo objectForKey:@"IOMACAddress"];
            if (!macData)
            {
                continue;
            }
            
            NSMutableString *macAddress = [[NSMutableString alloc] init];
            const UInt8 *bytes = [macData bytes];
            for (int i=0; i<macData.length; i++)
            {
                [macAddress appendFormat:@"%02x",*(bytes+i)];
            }
            
            //打印Mac地址
            if (bsdName && macAddress)
            {
                NSLog(@"网卡:%@\nMac地址:%@\n",bsdName,macAddress);
            }
        }
    }
    
    IOObjectRelease(iterator);
}