Paul Eggert wrote:
> If I configure current (f2e323430193956709aacca33f6b4fcab4fb9d8b)
> Coreutils with --enable-systemd on my Ubuntu 24.10 desktop, the output
> gets worse:
>
> $ ./who-no-systemd # Configured normally.
> eggert seat0 2025-02-15 10:11 (login screen)
> eggert tty2 2025-02-15 10:11 (tty2)
> $ ./who-with-systemd # Configured with --enable-systemd.
> eggert seat0 2025-02-15 10:11
> eggert tty2 2025-02-15 10:11
>
> Apparently for coreutils, /var/run/utmp (the traditional interface) has
> more info than libsystemd's API.
Both outputs are equivalent; the second one is less redundant.
- The comment "(tty2)" is redundant because it's already the tty.
- The comment "(login screen)" is redundant because that's the
concept of a "seat".
> Similarly, on a Fedora 41 desktop where I'm not currently logged in, I
> get inferior results when Coreutils is configured with --enable-systemd:
>
> $ ./who-no-systemd
> eggert pts/3 2025-02-16 22:56 (47.147.225.25)
> $ ./who-with-systemd
> gdm seat0 2025-02-13 18:04
> gdm tty1 2025-02-13 18:04
> eggert sshd pts/3 2025-02-16 22:56 (47.147.225.25)
>
> Here, though I'm logged in only via ssh, the libsystemd-using 'who'
> incorrectly reports that a user named "gdm" is logged in in person.
'who' merely reports the info it got from systemd-logind, and systemd-logind
most probably got a notification from gdm.
I agree with you that this _looks_like_ as if a user named 'gdm' was logged
in, and thus is misleading. But I don't think this should be fixed in
coreutils. Rather, this is something to work out between systemd-logind
and gdm.
Bruno
