Hi there,

The lib detects docx, xlsx, pptx (:tada:) but not the older format: doc, xls, ppt (:cry:).

I think it's not possible to distinguish them from another because they're all based on the Compound File Binary Format (Wikipedia says that) and there is a very well documented thread on Microsoft. 😠

However I'm not sure that there isn't a way by reading the 4100 first bytes (I will have a deeper look).

To me it would a very cool feature because users would be able to detect if the .doc uploaded is somehow legit. 🙏

Even the information that this is a Compound File Binary Format would be enough in my case (but I will do that only on my fork because I think that it out of the scope of this library).

Any thoughts on that feature?