UTTypeCreateBuiltinIdentifiersForTag.m

/**
 * Creates an array of all uniform type identifiers indicated
 *  by the specified tag under builtin tag classes
 * @inTag:              the tag string
 * @inConformingToUTI   the identifier of a type to which the result must conform
 * @return              a new CFArrayRef containing all type identifiers
 *                      NULL if no inConformingToUTI match or memory failure
 *                      Ownership follows the The Create Rule
 */
CFArrayRef UTTypeCreateBuiltinIdentifiersForTag(
        __nonnull CFStringRef inTag,
        __nullable CFStringRef inConformingToUTI)
{
    static CFStringRef tags[4];
    CFMutableArrayRef arr;
    CFStringRef iden;
    size_t i;

    tags[0] = kUTTagClassFilenameExtension;
    tags[1] = kUTTagClassOSType;
    tags[2] = kUTTagClassMIMEType;
    tags[3] = kUTTagClassNSPboardType;

    arr = CFArrayCreateMutable(kCFAllocatorDefault, ARRAY_SIZE(tags), &kCFTypeArrayCallBacks);
    if (arr != NULL) {
        for (i = 0; i < ARRAY_SIZE(tags); i++) {
            iden = UTTypeCreatePreferredIdentifierForTag(tags[i], inTag, inConformingToUTI);
            if (iden != NULL) CFArrayAppendValue(arr, iden);
        }
    }

    return arr;
}