iOS prevent files from being backed up

Back up iCloud and iTunes

Useful info if following How do I prevent files from being backed up to iCloud and iTunes?.

Document, Library

How to get these directory.

@implementation FilePathUtil

+ (NSString *)libPath {
    return [self path:NSLibraryDirectory];
}

+ (NSString *)docPath {
    return [self path:NSDocumentDirectory];
}

+ (NSString *)applicationSupport {
    return [self path:NSApplicationSupportDirectory];
}

+ (NSString *)path:(NSSearchPathDirectory)directory {
    NSArray *paths = NSSearchPathForDirectoriesInDomains(directory, NSUserDomainMask, YES);
    NSString *basePath = ([paths count] > 0) ? [paths objectAtIndex:0] : nil;
    return basePath;
}

@end

How to check file attr

This is NSURL category

@implementation NSURL(File)
// https://developer.apple.com/library/iOS/qa/qa1719/_index.html
- (BOOL)isExcludedFromBackup {
    NSError *error = nil;
    NSNumber *number = nil;
    [self getResourceValue:&number forKey:NSURLIsExcludedFromBackupKey error:&error];
    return !error && [number boolValue];
}
@end