How to append NSData to NSData in Objective-C?

Question

I m going to append NSData to NSData in Objective-C.

How can I do it?

Answer 1

 NSMutableData *first_data = [NSMutableData dataWithContentsOfURL:self.firstURL];
 NSMutableData *second_data = [NSMutableData dataWithContentsOfURL:self.secondURL];
 [first_data appendData:second_data];
 [first_data writeToURL:url atomically:YES];