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I have a MIME type: audio/x-wav

I want the preferred filename extension: .wav

Is there a way to obtain this information on iOS?

I have tried...

CFStringRef uttype = UTTypeCreatePreferredIdentifierForTag(kUTTagClassMIMEType, @"audio/x-wav", NULL);
CFStringRef utpt = UTTypeCopyPreferredTagWithClass(uttype, kUTTagClassFilenameExtension);

...but the value of 'uttype' returned is prefixed with "dyn" (indicates type-not-found according to the docs) and 'utpt' is therefore NULL.

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1 Answer 1

From what I understand, a UTI prefixed with dyn means that the UTI was hitherto unknown to the system and created a new, "dynamic" UTI because you asked it for information about a MIME type. Since the MIME type is unknown to the system, it obviously doesn't know what file extensions have the MIME type.

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So I guess the UTI stuff is a no-go. Is there another API that I can try? Thanks! –  strawtarget Dec 7 '10 at 1:41

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