Office filetypes? about filetype HOT 3 CLOSED

I do not know about the older types, but you cannot do xlsx, docx and the like without breaking your 261 byte guarantee. These are zip files, and accurately distinguishing them from one another will require you to dive much further into the file:

https://fossies.org/linux/misc/file-5.35.tar.gz:t/file-5.35/magic/Magdir/msooxml

To do this, you could enable a "deep scanning" mode that will make guarantees only that it does not need to scan past some value X, where X is the deepest possible match of all possible patterns. Otherwise, you're probably stuck with identifying these as .zip.

EDIT 2-3-19: update link

from filetype.

If we have the file signature schemas, we can support them easily. If you share someinfo about them or send a PR, I would not mind supporting them.

from filetype.

agree with @flowchartsman. file command correctly detects the filetype for a Microsoft Word 2007+ file, which is a ZIP file if you don't dive deep enough.

https://github.com/file/file/blob/master/magic/Magdir/msooxml#L30

from filetype.