[systemd-devel] [EXT] Re: Q: Querying units for "what provides" a target

[Michael Biebl]

Am Fr., 9. Sept. 2022 um 12:08 Uhr schrieb Ulrich Windl
<Ulrich.Windl at rz.uni-regensburg.de>:
>
> >>> Michael Biebl <mbiebl at gmail.com> schrieb am 09.09.2022 um 10:55 in
> Nachricht
> <CAGWsdOibC4k0CqxubSRKRV3ZU=xPpdeMYGnA8b4sC80hMDbqOg at mail.gmail.com>:
> > Example: syslog.service
> >
> > $ systemctl status syslog.service
> > ● rsyslog.service - System Logging Service
> >      Loaded: loaded (/lib/systemd/system/rsyslog.service; enabled;
> > preset: enabled)
> >      Active: active (running) since Thu 2022-09-08 08:55:45 CEST; 1 day 1h
> > ago
> > TriggeredBy: ● syslog.socket
> >        Docs: man:rsyslogd(8)
> >              man:rsyslog.conf(5)
> >              https://www.rsyslog.com/doc/
> >    Main PID: 624 (rsyslogd)
> >       Tasks: 4 (limit: 19002)
> >      Memory: 3.8M
> >         CPU: 1.341s
> >      CGroup: /system.slice/rsyslog.service
> >              └─624 /usr/sbin/rsyslogd -n -iNONE
> >
> > You'll see that syslog.service is provided by  provided by
> > rsyslog.service (and the actual name of the file on the disk)
> > Isn't this what you wanted? If not, I must have misunderstood what you
> > are looking for.
>
> Hi!
>
> I'm afraid that does not help:
> # systemctl status time-set.target
> ● time-set.target - System Time Set
>      Loaded: loaded (/usr/lib/systemd/system/time-set.target; static)
>      Active: active since Mon 2022-09-05 14:30:42 CEST; 3 days ago
>        Docs: man:systemd.special(7)
>
> Now what is actually providing "time-set" (if any)?
> Does that mean "nothing provides time-set"?
>
> Likewise:
> # systemctl status time-sync.target
> ● time-sync.target - System Time Synchronized
>      Loaded: loaded (/usr/lib/systemd/system/time-sync.target; static)
>      Active: active since Mon 2022-09-05 14:32:00 CEST; 3 days ago
>        Docs: man:systemd.special(7)
>
> Sep 05 14:32:00 host16 systemd[1]: Reached target System Time Synchronized.
>
> Clear now?

Not really.
Are you interested in what services hook into time-sync.target (and
are ordered before it)?