[Debian-ha-maintainers] Bug#807428: Bug#807428: csync2: socket activation and running as system user

[Ferenc Wágner]

Christoph Berg <myon at debian.org> writes:

> Re: Dhionel Díaz 2016-06-21 <0c44f8f5-4d46-60e7-2bc3-d1695686953a at cenditel.gob.ve>
>
>>> What about depending on inetd | systemd-sysv and invoking update-inetd
>>> only if systemd is not running?
>
> Doesn't that fail if the system is switched to/from systemd after the
> package was already installed?

Sure it does.  But if you do both, one (probably inetd, coming later)
will fail to bind if systemd manages the socket and also starts inetd.
Hmm, maybe you could have the csync2.socket conflict with inet.service
to avoid this failure mode...  That would serve csync2 via inetd instead
of systemd, which is inefficient, but maybe acceptable.

>>> Don't forget to depend on update-inetd as well.
>> 
>> Looks reasonable, in the following days I'll be sending a patch along
>> those lines. In a brief exploration I haven't found if there is a
>> recommended approach to detect systemd, do you think a test on the exit
>> status of 'stat -c %N /proc/1/exe | grep systemd' would be appropriate?
>
> The canonical test is "test -d /run/systemd/system".

Which is also more portable than using /proc.  Not that you could find
systemd where procsfs isn't supported...
-- 
Feri