User Profile

Hi, I have a strange problem. In my local network, I have some apple devices (including mac, iphone, ipad) and a windows computer. The windows pc and any of the apple devices can ping each other, while every two of the apple devices can't ping each other. Whether udp or tcp are in the same situation. As is the situation, the firewall/mask/local ip are not the problems. I can't use wireshark to debug, because there is not any packet between these apple devices. Does someone know what the problem it may be? Or could someone tell me how to debug this? Thanks in advance!

My code is as follow: let img = UIImage(named: "in00c.png") guard let data = CFDataGetBytePtr(img!.cgImage!.dataProvider!.data) else {           fatalError("Couldn't access image data")         } print(data[0]) it crashes at last line print(data[0]), due to EXC_BAD_ACCESS (code=1, address=0x1074e8000) Does I have something wrong with the code? I am using the latest Xcode, seems it works ok in previous versions.