title: Keep a reference to a file after it has moved in objective-c?
body: <p>I have a Cocoa application that stores a reference to multimedia files (images, videos, etc) on the user's computer.  I'm wondering if there is a way to get a reference to that file other that using a file path so that if the user moves that file to a different folder on their computer, I would still know where it is.  I'm currently storing the array of file paths that are passed back from the standard Cocoa open dialogue:</p>
  
  <pre><code>-(void)addMultimediaDidEnd:(NSOpenPanel*)sheet
             returnCode:(int)returnCode
            contextInfo:(NSString *)contextInfo 
  {   
      if(returnCode == NSOKButton) {
          [sheet orderOut:nil];
          [self saveFiles:[sheet filenames]];
      }
  }
  </code></pre>