[bug#30216] [WIP v5] services: agetty: Make tty optional.

[Danny Milosavljevic]

Hi Ludo,

> I think this would work:
> 
>   (let* ((consoles     (find-long-option "console" (linux-command-line)))
>          (console-ttys (remove (lambda (console)
>                                  (string-prefix? "tty" console))
>                                (string-tokenize consoles not-comma))))

"ttyS0" starts with "tty" but should not be removed...

> Maybe default to /dev/ttyS0?

Sounds unsafe.  Also, on x86_64 that's not really useful either.  It would be
good to have a way to the not start the service after all in that case.