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 solves the problem that modprobe does not know about $MODULE_DIR
when run via sudo, and instead wrongly tries to read /lib/modules/:
$ sudo strace -efile modprobe foo |& grep modules
open("/lib/modules/3.14.37/modules.softdep", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/modules/3.14.37/modules.dep.bin", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/modules/3.14.37/modules.dep.bin", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
open("/lib/modules/3.14.37/modules.alias.bin", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
Without this patch, one would have to use sudo -E (preserves environment
vars). But that option is reserved for sudo users with extra rights
(SETENV), so it's not a solution.
environment.sessionVariables are set by PAM, so they are included in the
environment used by sudo.
We already have separate tests for checking whether the ISO boots
correctly, so it's not necessary to do that here. So now
tests/installer.nix just tests nixos-install, from a regular NixOS VM
that uses the host's Nix store. This makes running the tests more
convenient because we don't have to build a new ISO after every
change.
