How to get vlc log in MobileVLCKit?

[hsc]

Hello :
Anyone knows how to get vlc log in MobileVLCKit?
I add "-vvv" or "-vvvv" in VLCLibrary of MobileVLCKit.
Just like :
////////////////////////////////////////////////
- (NSArray *)_defaultOptions
{
NSArray *vlcParams = [[NSUserDefaults standardUserDefaults] objectForKey:@"VLCParams"];
#if TARGET_OS_IPHONE
if (!vlcParams) {
vlcParams = @[@"--no-color",
@"--no-osd",
@"--no-video-title-show",
@"--no-stats",
@"-vvv",
#ifndef NOSCARYCODECS
@"--avcodec-fast",
#endif
@"--verbose=0",
@"--text-renderer=quartztext",
@"--avi-index=3",
@"--extraintf=ios_dialog_provider"];
}
#else
if (!vlcParams) {
NSMutableArray *defaultParams = [NSMutableArray array];
[defaultParams addObject:@"--play-and-pause"]; // We want every movie to pause instead of stopping at eof
[defaultParams addObject:@"--no-color"]; // Don't use color in output (Xcode doesn't show it)
[defaultParams addObject:@"--no-video-title-show"]; // Don't show the title on overlay when starting to play
[defaultParams addObject:@"--verbose=4"]; // Let's not wreck the logs
[defaultParams addObject:@"--no-sout-keep"];
[defaultParams addObject:@"--vout=macosx"]; // Select Mac OS X video output
[defaultParams addObject:@"--text-renderer=quartztext"]; // our CoreText-based renderer
[defaultParams addObject:@"--extraintf=macosx_dialog_provider"]; // Some extra dialog (login, progress) may come up from here

[[NSUserDefaults standardUserDefaults] setObject:defaultParams forKey:@"VLCParams"];
[[NSUserDefaults standardUserDefaults] synchronize];

vlcParams = defaultParams;
}
#endif

return vlcParams;
}
////////////////////////////////////////////////
But the log still not show.
Anyone could help me?
Thanks.