'\" t .TH "ENVIRONMENT\&.D" "5" "" "systemd 255" "environment.d" .\" ----------------------------------------------------------------- .\" * Define some portability stuff .\" ----------------------------------------------------------------- .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .\" http://bugs.debian.org/507673 .\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html .\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" ----------------------------------------------------------------- .\" * set default formatting .\" ----------------------------------------------------------------- .\" disable hyphenation .nh .\" disable justification (adjust text to left margin only) .ad l .\" ----------------------------------------------------------------- .\" * MAIN CONTENT STARTS HERE * .\" ----------------------------------------------------------------- .SH "NAME" environment.d \- Definition of user service environment .SH "SYNOPSIS" .PP ~/\&.config/environment\&.d/*\&.conf .PP /etc/environment\&.d/*\&.conf .PP /run/environment\&.d/*\&.conf .PP /usr/lib/environment\&.d/*\&.conf .PP /etc/environment .SH "DESCRIPTION" .PP Configuration files in the environment\&.d/ directories contain lists of environment variable assignments passed to services started by the systemd user instance\&. \fBsystemd-environment-d-generator\fR(8) parses them and updates the environment exported by the systemd user instance\&. See below for an discussion of which processes inherit those variables\&. .PP It is recommended to use numerical prefixes for file names to simplify ordering\&. .PP For backwards compatibility, a symlink to /etc/environment is installed, so this file is also parsed\&. .SH "CONFIGURATION DIRECTORIES AND PRECEDENCE" .PP 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/\&. .PP 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)\&. .PP 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\&. It is recommended to use the range 10\-40 for configuration files in /usr/ and the range 60\-90 for configuration files in /etc/ and /run/, to make sure that local and transient configuration files will always take priority over configuration files shipped by the OS vendor\&. .PP 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\&. .SH "CONFIGURATION FORMAT" .PP The configuration files contain a list of "\fIKEY\fR=\fIVALUE\fR" 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 "${\fIFOO\fR:\-\fIDEFAULT_VALUE\fR}" to expand in the same way as "${\fIFOO\fR}" unless the expansion would be empty, in which case it expands to \fIDEFAULT_VALUE\fR, and use "${\fIFOO\fR:+\fIALTERNATE_VALUE\fR}" to expand to \fIALTERNATE_VALUE\fR as long as "${\fIFOO\fR}" would have expanded to a non\-empty value\&. No other elements of shell syntax are supported\&. .PP Each \fIKEY\fR must be a valid variable name\&. Empty lines and lines beginning with the comment character "#" are ignored\&. .SS "Example" .PP \fBExample\ \&1.\ \&Setup environment to allow access to a program installed in /opt/foo\fR .PP /etc/environment\&.d/60\-foo\&.conf: .sp .if n \{\ .RS 4 .\} .nf 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/} .fi .if n \{\ .RE .\} .SH "APPLICABILITY" .PP Environment variables exported by the user service manager (\fBsystemd \-\-user\fR instance started in the user@\fIuid\fR\&.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, \fBsystemd.service\fR(5) units contain programs launched by systemd, and \fBsystemd.scope\fR(5) units contain programs launched by something else\&. .PP 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\*(Aqs environment block the environment must be modified before the user\*(Aqs service manager is invoked, for example from the system service manager or via a PAM module\&. .PP Specifically, for ssh logins, the \fBsshd\fR(8) service builds an environment that is a combination of variables forwarded from the remote system and defined by \fBsshd\fR, see the discussion in \fBssh\fR(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 \fBsystemctl show\-environment\fR or the underlying D\-Bus call\&. .SH "SEE ALSO" .PP \fBsystemd\fR(1), \fBsystemd-environment-d-generator\fR(8), \fBsystemd.environment-generator\fR(7)