NAME

       environment.d - Definition of user service environment

SYNOPSIS

       ~/.config/environment.d/*.conf

       /etc/environment.d/*.conf

       /run/environment.d/*.conf

       /usr/lib/environment.d/*.conf

       /etc/environment

DESCRIPTION

       Configuration files in the environment.d/ directories contain lists of environment variable assignments
       for services started by the systemd user instance.  systemd-environment-d-generator(8) parses them and
       updates the environment exported by the systemd user instance. See below for an discussion of which
       processes inherit those variables.

       It is recommended to use numerical prefixes for file names to simplify ordering.

       For backwards compatibility, a symlink to /etc/environment is installed, so this file is also parsed.

CONFIGURATION DIRECTORIES AND PRECEDENCE

       Configuration files are read from directories in /etc/, /run/, /usr/local/lib/, and /lib/, in order of
       precedence, as listed in the SYNOPSIS section above. Files must have the ".conf" extension. Files in
       /etc/ override files with the same name in /run/, /usr/local/lib/, and /lib/. Files in /run/ override
       files with the same name under /usr/.

       All configuration files are sorted by their filename in lexicographic order, regardless of which of the
       directories they reside in. If multiple files specify the same option, the entry in the file with the
       lexicographically latest name will take precedence. Thus, the configuration in a certain file may either
       be replaced completely (by placing a file with the same name in a directory with higher priority), or
       individual settings might be changed (by specifying additional settings in a file with a different name
       that is ordered later).

       Packages should install their configuration files in /usr/lib/ (distribution packages) or /usr/local/lib/
       (local installs). Files in /etc/ are reserved for the local administrator, who may use this logic to
       override the configuration files installed by vendor packages. It is recommended to prefix all filenames
       with a two-digit number and a dash, to simplify the ordering of the files.

       If the administrator wants to disable a configuration file supplied by the vendor, the recommended way is
       to place a symlink to /dev/null in the configuration directory in /etc/, with the same filename as the
       vendor configuration file. If the vendor configuration file is included in the initrd image, the image
       has to be regenerated.

CONFIGURATION FORMAT

       The configuration files contain a list of "KEY=VALUE" environment variable assignments, separated by
       newlines. The right hand side of these assignments may reference previously defined environment
       variables, using the "${OTHER_KEY}" and "$OTHER_KEY" format. It is also possible to use
       "${FOO:-DEFAULT_VALUE}" to expand in the same way as "${FOO}" unless the expansion would be empty, in
       which case it expands to DEFAULT_VALUE, and use "${FOO:+ALTERNATE_VALUE}" to expand to ALTERNATE_VALUE as
       long as "${FOO}" would have expanded to a non-empty value. No other elements of shell syntax are
       supported.

       Each KEY must be a valid variable name. Empty lines and lines beginning with the comment character "#"
       are ignored.

   Example
       Example 1. Setup environment to allow access to a program installed in /opt/foo

       /etc/environment.d/60-foo.conf:

                   FOO_DEBUG=force-software-gl,log-verbose
                   PATH=/opt/foo/bin:$PATH
                   LD_LIBRARY_PATH=/opt/foo/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}
                   XDG_DATA_DIRS=/opt/foo/share:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share/}

APPLICABILITY

       Environment variables exported by the user manager (systemd --user instance started in the
       user@uid.service system service) apply to any services started by that manager. In particular, this may
       include services which run user shells. For example in the GNOME environment, the graphical terminal
       emulator runs as the gnome-terminal-server.service user unit, which in turn runs the user shell, so that
       shell will inherit environment variables exported by the user manager. For other instances of the shell,
       not launched by the user manager, the environment they inherit is defined by the program that starts
       them. Hint: in general, systemd.service(5) units contain programs launched by systemd, and
       systemd.scope(5) units contain programs launched by something else.

       Specifically, for ssh logins, the sshd(8) service builds an environment that is a combination of
       variables forwarded from the remote system and defined by sshd, see the discussion in ssh(1). A graphical
       display session will have an analogous mechanism to define the environment. Note that some managers query
       the systemd user instance for the exported environment and inject this configuration into programs they
       start, using systemctl show-environment or the underlying D-Bus call.

SEE ALSO

       systemd(1), systemd-environment-d-generator(8), systemd.environment-generator(7)