main: Add systemd run0 equivalent to sudo

[ColinKinloch]

I suspect these changes are incorrect or incomplete.
Is the second value a list of single letter flags arguments? Should it be Cgprtu:AEHPSbilns:eKkVv?
run0 is a systemd 256 alternative to sudo.

[danielshahaf]

Is the second value a list of single letter flags arguments?

The middle value is list of single-letter flags that don't take arguments. E.g., 'sudo -u foo' uses 'foo' as an argument to '-u', so sudo's "u" is before the first colon; but 'sudo -l foo' interprets 'foo' as a positional argument, hence sudo's '-l' is in the middle group. Lines 35 through 337 were supposed to make this clear, but there's room for improvement.

[ColinKinloch]

That makes sense, thanks.
In that case the only options are ugD each taking an argument.
And -h which seems to be intentionally omitted.

[danielshahaf]

And `-h` which seems to be intentionally omitted.

I do see a -h in <https://man.archlinux.org/man/run0.1.en>. Could you add a comment stating the run0 version referenced? That's helpful down the road when looking for what flags were added/changed (we can just go through the upstream changelog, or diff upstream's man page source between tags). Other than that, LGTM, but I'll defer to others to do the actual merge.

[ColinKinloch]

I do see a -h in https://man.archlinux.org/man/run0.1.en.

Ah, never mind. I was confused by the absence of h in sudo. having an option switch meanings seems like a bad idea 🤔 .

I've added h and noted that it's systemd 256.6