how to get the path and url of the temp image ?

I capture a image of webview that playing a flash. Because I want to show this image and use the IKSaveOptions to save the image .but I found the path of image is nil, Now I want to get the path of image , How to do ?
my code:
NSString *path = [[NSBundle mainBundle] pathForResource: ?? ofType:??];
NSURL *url = [NSURL fileURLWithPath: path];
then I use the url to show the image in the imageview,but Now I didn't get the path ,Thanks a lot!