Yeah, I get it. I’ve had many libraries fail me in as many ways, which is why I consider it lucky to not have to implement my own. I work in .net these days, but there have been times where I had to just dig into the xml inside the xlsx and use xml tools. Those were mostly one-offs, thankfully.

Back when I did Java I had a frustrating experience with IBM’s libxml causing our app to crash after several days due to a memory leak. I didn’t have access to the production environment so it took me probably 3 weeks to find the cause and only after digging through a crash dump provided by the sysadmin. Not related, but you triggered my traumatic memory :)

I don’t know what you’re trying to do with Excel, but based on your posts, I can only wish you good luck. I’m happy to say that I have been able to outsource low level parsing to third party libraries for my needs so far. Well, except the interpreting semantic formatting part. That was on me.

You need another dragon for Excel and its two date systems.