Proper URL path escaping in Cocoa

Don't do this:

NSString *escaped = [path stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

Do this:

CFStringRef escaped = CFURLCreateStringByAddingPercentEscapes(NULL,
                                                          (CFStringRef)path,
                                                          NULL,
                                                          CFSTR(";?#"),
                                                          kCFStringEncodingUTF8);