Importing the full environment is convenient, but it doesn't work too well in
practice, because we get a metric ton of shell-specific crap that should never
end up in the global environment block:
$ systemctl --user show-environment
...
SHELL=/bin/zsh
AUTOJUMP_ERROR_PATH=/home/zbyszek/.local/share/autojump/errors.log
AUTOJUMP_SOURCED=1
CONDA_SHLVL=0
CVS_RSH=ssh
DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus
DESKTOP_SESSION=gnome
DISPLAY=:0
FPATH=/usr/share/Modules/init/zsh-functions:/usr/local/share/zsh/site-functions:/usr/share/zsh/site-functions:/usr/share/zsh/5.8/functions
GDMSESSION=gnome
GDM_LANG=en_US.UTF-8
GNOME_SETUP_DISPLAY=:1
GUESTFISH_INIT=$'\\e[1;34m'
GUESTFISH_OUTPUT=$'\\e[0m'
GUESTFISH_PS1=$'\\[\\e[1;32m\\]><fs>\\[\\e[0;31m\\] '
GUESTFISH_RESTORE=$'\\e[0m'
HISTCONTROL=ignoredups
HISTSIZE=1000
LOADEDMODULES=
OLDPWD=/home/zbyszek
PWD=/home/zbyszek
QTDIR=/usr/lib64/qt-3.3
QTINC=/usr/lib64/qt-3.3/include
QTLIB=/usr/lib64/qt-3.3/lib
QT_IM_MODULE=ibus
SDL_VIDEO_MINIMIZE_ON_FOCUS_LOSS=0
SESSION_MANAGER=local/unix:@/tmp/.ICE-unix/2612,unix/unix:/tmp/.ICE-unix/2612
SHLVL=0
STEAM_FRAME_FORCE_CLOSE=1
TERM=xterm-256color
USERNAME=zbyszek
WISECONFIGDIR=/usr/share/wise2/
...
Plenty of shell-specific and terminal-specific stuff that have no global
significance.
Let's start warning when this is used to push people towards importing only
specific variables.
Putative NEWS entry:
* systemctl import-environment will now emit a warning when called without
any arguments (i.e. to import the full environment block of the called
program). This command will usually be invoked from a shell, which means
that it'll inherit a bunch of variables which are specific to that shell,
and usually to the tty the shell is connected to, and don't have any
meaning in the global context of the system or user service manager.
Instead, only specific variables should be imported into the manager
environment block.
Similarly, programs which update the manager environment block by directly
calling the D-Bus API of the manager, should also push specific variables,
and not the full inherited environment.
32854f7044