environment.d(5) — Linux manual page


ENVIRONMENT.D(5)              environment.d             ENVIRONMENT.D(5)

NAME         top

       environment.d - Definition of user service environment

SYNOPSIS         top


DESCRIPTION         top

       Configuration files in the environment.d/ directories contain
       lists of environment variable assignments passed to 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 files are read from directories in /etc/, /run/,
       /usr/local/lib/, and /usr/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 /usr/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

       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.


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




       Environment variables exported by the user service manager
       (systemd --user instance started in the user@uid.service system
       service) are passed to any services started by that service
       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 service
       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.

       Note that these files do not affect the environment block of the
       service manager itself, but exclusively the environment blocks
       passed to the services it manages. Environment variables set that
       way thus cannot be used to influence behaviour of the service
       manager. In order to make changes to the service manager's
       environment block the environment must be modified before the
       user's service manager is invoked, for example from the system
       service manager or via a PAM module.

       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         top

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

COLOPHON         top

       This page is part of the systemd (systemd system and service
       manager) project.  Information about the project can be found at
       ⟨http://www.freedesktop.org/wiki/Software/systemd⟩.  If you have
       a bug report for this manual page, see
       This page was obtained from the project's upstream Git repository
       ⟨https://github.com/systemd/systemd.git⟩ on 2023-12-22.  (At that
       time, the date of the most recent commit that was found in the
       repository was 2023-12-22.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to

systemd 255                                             ENVIRONMENT.D(5)

Pages that refer to this page: systemd.directives(7)systemd.index(7)systemd-environment-d-generator(8)