Antonio,

Many thanks for this and welcome to Devuan!

I think there are 2 distinct issues here.

On Sat, Oct 22, 2022 at 06:44:09PM +0200, Antonio Rendina wrote:
> When I leave the system on its own at some point it should go on
> suspend-mode. But this was not happening, so I started to dig in. In my
> understanding, the suspend mode is set by xfce4-power-manager but is handled
> by elogind. I noticed that xscreensaver is compiled with libsystemd and it
> generates a binary called xscreensaver-systemd that was actually running on
> my laptop.
> My theory is that xscreensaver is calling the api, but systemd is not there
> and so it generates the error that is blocking my laptop from going into
> suspend mode.

I doubt this. Reading man xscreensaver-systemd(1), it is specifically for both
systemd and elogind integration. That sounds like Devuan elogind systems might
find it useful, at least sometimes.

In terms of its function the manpage also says:

  * When another process on the system asks for the screen saver to be inhibited
    (e.g. because a video is playing) this program periodically runs
    xscreensaver-command -deactivate to keep the display un-blanked.  It does
    this until the other program asks for it to stop, or exits.  It does this
    through the org.freedesktop.ScreenSaver(5) D-Bus interface.

I suspect this may be the cause of your laptop not suspending. I suggest
monitoring the bus and seeing if anything might be sending thoses messages.

> IMHO, we should work on cleaning software from libsystemd, and I could take
> care of this one, and maybe other packages considering that I'm learning how
> to do that.

This has been discussed on several occassions. For Devuan Jessie, libsystemd0
integration was removed. Since ascii, it has generally been left intact as
either non-functional and not worth the considerable time and effort to remove
and maintain or potentially useful to desktop systems now optional runtime
logind functionality is available via elogind.

The libelogind0 api is binary equivalent with libsystemd0 and so we don't have
to recompile anything.

> I don't know if you agree with that, I mean it's Devuan purpose to not use
> systemd as init system, but I don't actually know how is your discussion
> about using it as a library. Should we clean up at least the base system?

The exception to this is been apt and we fork that not to depend on libsystemd0
to minimise dependencies and potential for breakage.

It, perhaps, depends on what you mean by base system here. Console only server?
Certainly that was the driver for forking apt. Or do you mean desktop base
system?

> BTW, this is a bug to me, so if you agree, I would also like to open a bug
> and provide the solution, but I will need a bit of help about how to do it.

See man reportbug(1) to help you format and send an email to
https://bugs.devuan.org.

Best wishes

Mark