read a filename from the user
Honestly for something repetitive like this I’d suggest trying to avoid user interaction completely. It’s probably better to get that info from the DVD drive itself (blkid -o value -s LABEL /dev/dvd
), or if that fails assign a number.
If by GNUIX you mean GNU Guix, they yeah it’s good enough. I’ve tried it on real hardware and didn’t find any issues. I would consider switching to it, but my day job is Nix-related so I’m running NixOS to make things easier. The learning curve is really steep for both Guix and Nix but I think their approach is great in the long term and worth investing some time into.