This is another of those “obligatory” posts, that don’t make much sense in the wider discussion of console software.
ssconvert is a tool that is bundled with gnumeric, the graphical spreadsheet tool that is occasionally touted as a lightweight alternative to the OpenOffice (LibreOffice? I forget what it’s called these days … I don’t use it, as you can tell) suite.
And it’s true,
ssconvert will — given the chance and a proper set of flags — convert into and out of gnumeric format without the need to load up X, start the desktop arena, open Gnumeric, open the file, hit “Save as,” pick a format and click on OK.
“At what cost?” is the question you should probably be asking. As far as I know, ssconvert doesn’t get bundled by itself (I’m speaking for Arch and Debian, neither of which seems to have an “ssconvert” package on its own, or even a collection on nongraphical tools from the gnumeric suite).
On top of that, the Arch version by default pulls in some Gnome-esque dependencies — like gtk3, polkit and dconf. Those are usually warning signs for me. My skin crawls at the sight of them. (And I should add, they take up about 184Mb on my machine. That’s rather large.)
So yes, it’s true, there is a command-line tool that will convert spreadsheet formats, primarily intended for gnumeric, and with a good measure of flexibility. 😐
The downside is, it comes with an aaawful lot of baggage. 😕