Or else users may see this unfriendly message:
error: cannot coerce null to a string, at .../nixos/modules/services/x11/display-managers/gdm.nix:107:49
Changes the option and explicitely sets it for each desktopManager.
Reasoning: Currently,
services.xserver.displayManager.desktopManagerHandlesLidAndPower is set
to true by default. This creates a problem for users without desktop
environments activated, since lid management simply doesn't work
(and they have to be lucky to find this option).
See issue #9671
This is needed by most window managers. Desktop environments
usually launch dbus-launch if a session hasn't been started yet
so this shouldn't hurt. The worst it can happen is that one
dbus session will be unused in case it's started twice.
The GDM change is backported from recent gdm.
With this patch, systemd-inhibit outputs a descriptive message when
desktopManagerHandlesLidAndPower=true (the default).
Before the patch:
$ systemd-inhibit
Who: /nix/store/[...]-xsession [...] (UID 1000/cassou, PID 18561/systemd-inhibit)
What: handle-power-key:handle-lid-switch
Why: Unknown reason
Mode: block
After the patch:
$ systemd-inhibit
Who: /nix/store/[...]-xsession [...] (UID 1000/cassou, PID 18561/systemd-inhibit)
What: handle-power-key:handle-lid-switch
Why: See NixOS configuration option 'services.xserver.displayManager.desktopManagerHandlesLidAndPower' for more information.
Mode: block
This was lost back in
ffedee6ed5. Getting this to work is
slightly tricky because ssh-agent runs as a user unit, and so doesn't
know the user's $DISPLAY.
Any reasonably new version of fontconfig does search that path by default,
and setting this globally causes problems, as 2.10 and 2.11 need
incompatible configs.
Tested: slim+xfce desktop, chrootenv-ed steam.
I have no idea why we were setting the global variable;
e.g., neither Fedora nor Ubuntu does that.
Option defaults should not refer to store paths, because they cause
the manual to be rebuilt gratuitously. It's especially bad to refer to
a highly variable path like a computed configuration file.
Should bring most of the examples into a better consistency regarding
syntactic representation in the manual.
Thanks to @devhell for reporting.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>
