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 of e.g. mutt not finding mail unless the user
sets MAIL=/var/spool/mail/$USER.
The default MAIL variable seems come from bash. Reasons for adding
symlink instead of changing MAIL default in bash:
- No need to rebuild world
- FHS recommends /var/mail over /var/spool/mail anyway[1]. Better fix
NixOS mail location than change MAIL in bash to something that doesn't
work on non-NixOS (however unlikely that users run nixpkgs bash on a
non-NixOS distro...).
[1] http://www.pathname.com/fhs/pub/fhs-2.3.html#VARMAILUSERMAILBOXFILES
Better replace the double quotes in 'echo "${commands}"' with single
quotes, to prevent the shell from doing command substitution etc. at
configuration build time.
Currently the module hardcodes the systemd service user to "marathon".
With this change one would not need to create an extra systemd config to
override the user.
So why would one need to override the Marathon user? Some apps require
root access to run. You can't run those with Marathon unless you
override the default user to root. Marathon also provides a
`--mesos_user` command line flag which allows you to run apps using
arbitrary users. You need to run the framework as root to enable this
functionality.
