Get MP3 info from remote file

I was playing around with the iPhone SDK and I wanted to get mp3 info from a remote file:

NSString *filepath = @"http://www.server.com/legal.mp3";
CFURLRef audioFileURL = CFURLCreateWithString(NULL, (CFStringRef) filepath, NULL);

AudioFileID audioFile;
if (noErr != AudioFileOpenURL(audioFileURL, fsRdPerm, 0, nil)) {
NSLog(@"Error - : could not open audio file. Path given was: %@", aud开发者_如何学CioFileURL);
}

Why doesn't this work? What am I doing wrong?

Thanks in advance.

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It's not possible with remote mp3 file... :(