Re: s6-rc user services on Gentoo

[Guillermo <gdiazhartusch@gmail.com>]

El mié, 3 abr 2024 a las 8:37, Laurent Bercot escribió:
>
> >2) The presence of a notification-fd file tells s6 that dbus-daemon
> >can be somehow coerced into producing an s6-style readiness
> >notification using file descriptor 3 without changing its code, are
> >you sure that's the case with this script? My service definition for
> >the system-wide message bus polls for readiness using s6-notifyoncheck
> >and a dbus-send command...
>
>   "dbus-daemon --print-address=3" should produce a suitable notification.
> The address of the bus can only be printed once the bus exists. :)

But then, there is a problem if one actually wants the server address
information that --print-address provides. Alexis' 'run' script for
example wants to save that to a file (apparently in a directory
suitable for s6-envdir). If the output is sent to the notification
pipe instead, s6-supervise will 'eat' it while waiting for the final
newline character, and then the information is lost.

And more generally, there's also the question about how 'ready'
dbus-daemon actually is when the point in its code that prints the
server address is reached. I can't really say without looking at the
code; dbus-daemon has many duties once its UNIX domain socket is
bound.

G.