Cocoa writeToFile: with a specific UTI

My app exports to CVS but Numbers won't open it because it dosen't have the public.comma-separated-values-text UTI. 开发者_如何学GoIs there a simple way to apply the UTI to the file as im writing it or do I have to declare it in info.plist? I don't want my app to open CVS files, it just needs to export it's data.

Thanks for any help

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Numbers or Excel opens CSV files, not CVS files. You see, they are C omma S eparated V alues :) The system automatically assigns the UTI. So, use the extension .csv. CVS is a name of a Drug Store chain.