[libreplanet-discuss] accessing .xls files

[Catonano]

is there a free software/open source tool to access xls files ?

I'd like to use it in GuixSD (possibly packaging it for GuixSD) so Apache POI is not viable because Java support in GuixSD is absent (for now)

There's xlsx2csv made with python, it works like a charm with xlsx files but not xls :-/

Are there any other options that I don't know of ?

Thanks in advance