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SYSTEMD.EXEC(5) | systemd.exec | SYSTEMD.EXEC(5) |
NAME¶
systemd.exec - Execution environment configurationSYNOPSIS¶
service.service, socket.socket, mount.mount, swap.swapDESCRIPTION¶
Unit configuration files for services, sockets, mount points, and swap devices share a subset of configuration options which define the execution environment of spawned processes. This man page lists the configuration options shared by these four unit types. See systemd.unit(5) for the common options of all unit configuration files, and systemd.service(5), systemd.socket(5), systemd.swap(5), and systemd.mount(5) for more information on the specific unit configuration files. The execution specific configuration options are configured in the [Service], [Socket], [Mount], or [Swap] sections, depending on the unit type.OPTIONS¶
WorkingDirectory=Takes an absolute directory path. Sets the working
directory for executed processes. If not set, defaults to the root directory
when systemd is running as a system instance and the respective user's home
directory if run as user.
RootDirectory=
Takes an absolute directory path. Sets the root directory
for executed processes, with the chroot(2) system call. If this is
used, it must be ensured that the process and all its auxiliary files are
available in the chroot() jail.
User=, Group=
Sets the Unix user or group that the processes are
executed as, respectively. Takes a single user or group name or ID as
argument. If no group is set, the default group of the user is chosen.
SupplementaryGroups=
Sets the supplementary Unix groups the processes are
executed as. This takes a space-separated list of group names or IDs. This
option may be specified more than once in which case all listed groups are set
as supplementary groups. When the empty string is assigned the list of
supplementary groups is reset, and all assignments prior to this one will have
no effect. In any way, this option does not override, but extends the list of
supplementary groups configured in the system group database for the
user.
Nice=
Sets the default nice level (scheduling priority) for
executed processes. Takes an integer between -20 (highest priority) and 19
(lowest priority). See setpriority(2) for details.
OOMScoreAdjust=
Sets the adjustment level for the Out-Of-Memory killer
for executed processes. Takes an integer between -1000 (to disable OOM killing
for this process) and 1000 (to make killing of this process under memory
pressure very likely). See proc.txt[1] for details.
IOSchedulingClass=
Sets the IO scheduling class for executed processes.
Takes an integer between 0 and 3 or one of the strings none,
realtime, best-effort or idle. See ioprio_set(2)
for details.
IOSchedulingPriority=
Sets the IO scheduling priority for executed processes.
Takes an integer between 0 (highest priority) and 7 (lowest priority). The
available priorities depend on the selected IO scheduling class (see above).
See ioprio_set(2) for details.
CPUSchedulingPolicy=
Sets the CPU scheduling policy for executed processes.
Takes one of other, batch, idle, fifo or
rr. See sched_setscheduler(2) for details.
CPUSchedulingPriority=
Sets the CPU scheduling priority for executed processes.
The available priority range depends on the selected CPU scheduling policy
(see above). For real-time scheduling policies an integer between 1 (lowest
priority) and 99 (highest priority) can be used. See
sched_setscheduler(2) for details.
CPUSchedulingResetOnFork=
Takes a boolean argument. If true, elevated CPU
scheduling priorities and policies will be reset when the executed processes
fork, and can hence not leak into child processes. See
sched_setscheduler(2) for details. Defaults to false.
CPUAffinity=
Controls the CPU affinity of the executed processes.
Takes a space-separated list of CPU indices. This option may be specified more
than once in which case the specificed CPU affinity masks are merged. If the
empty string is assigned, the mask is reset, all assignments prior to this
will have no effect. See sched_setaffinity(2) for details.
UMask=
Controls the file mode creation mask. Takes an access
mode in octal notation. See umask(2) for details. Defaults to
0022.
Environment=
Sets environment variables for executed processes. Takes
a space-separated list of variable assignments. This option may be specified
more than once in which case all listed variables will be set. If the same
variable is set twice, the later setting will override the earlier setting. If
the empty string is assigned to this option, the list of environment variables
is reset, all prior assignments have no effect. Variable expansion is not
performed inside the strings, however, specifier expansion is possible. The $
character has no special meaning. If you need to assign a value containing
spaces to a variable, use double quotes (") for the assignment.
Example:
gives three variables "VAR1", "VAR2", "VAR3" with
the values "word1 word2", "word3", "$word 5 6".
See environ(7) for details about environment variables.
EnvironmentFile=
Environment="VAR1=word1 word2" VAR2=word3 "VAR3=$word 5 6"
Similar to Environment= but reads the environment
variables from a text file. The text file should contain new-line-separated
variable assignments. Empty lines and lines starting with ; or # will be
ignored, which may be used for commenting. A line ending with a backslash will
be concatenated with the following one, allowing multiline variable
definitions. The parser strips leading and trailing whitespace from the values
of assignments, unless you use double quotes (").
The argument passed should be an absolute filename or wildcard expression,
optionally prefixed with "-", which indicates that if the file does
not exist, it will not be read and no error or warning message is logged. This
option may be specified more than once in which case all specified files are
read. If the empty string is assigned to this option, the list of file to read
is reset, all prior assignments have no effect.
The files listed with this directive will be read shortly before the process is
executed (more specifically, after all processes from a previous unit state
terminated. This means you can generate these files in one unit state, and
read it with this option in the next). Settings from these files override
settings made with Environment=. If the same variable is set twice from
these files, the files will be read in the order they are specified and the
later setting will override the earlier setting.
StandardInput=
Controls where file descriptor 0 (STDIN) of the executed
processes is connected to. Takes one of null, tty,
tty-force, tty-fail or socket. If null is
selected, standard input will be connected to /dev/null, i.e. all read
attempts by the process will result in immediate EOF. If tty is
selected, standard input is connected to a TTY (as configured by
TTYPath=, see below) and the executed process becomes the controlling
process of the terminal. If the terminal is already being controlled by
another process, the executed process waits until the current controlling
process releases the terminal. tty-force is similar to tty, but
the executed process is forcefully and immediately made the controlling
process of the terminal, potentially removing previous controlling processes
from the terminal. tty-fail is similar to tty but if the
terminal already has a controlling process start-up of the executed process
fails. The socket option is only valid in socket-activated services,
and only when the socket configuration file (see systemd.socket(5) for
details) specifies a single socket only. If this option is set, standard input
will be connected to the socket the service was activated from, which is
primarily useful for compatibility with daemons designed for use with the
traditional inetd(8) daemon. This setting defaults to
null.
StandardOutput=
Controls where file descriptor 1 (STDOUT) of the executed
processes is connected to. Takes one of inherit, null,
tty, syslog, kmsg, journal, syslog+console,
kmsg+console, journal+console or socket. If set to
inherit, the file descriptor of standard input is duplicated for
standard output. If set to null, standard output will be connected to
/dev/null, i.e. everything written to it will be lost. If set to tty,
standard output will be connected to a tty (as configured via TTYPath=,
see below). If the TTY is used for output only, the executed process will not
become the controlling process of the terminal, and will not fail or wait for
other processes to release the terminal. syslog connects standard
output to the syslog(3) system syslog service. kmsg connects it
with the kernel log buffer which is accessible via dmesg(1).
journal connects it with the journal which is accessible via
journalctl(1) (Note that everything that is written to syslog or kmsg
is implicitly stored in the journal as well, those options are hence supersets
of this one). syslog+console, journal+console and
kmsg+console work similarly but copy the output to the system console
as well. socket connects standard output to a socket from socket
activation, semantics are similar to the respective option of
StandardInput=. This setting defaults to the value set with
DefaultStandardOutput= in systemd-system.conf(5), which defaults
to journal.
StandardError=
Controls where file descriptor 2 (STDERR) of the executed
processes is connected to. The available options are identical to those of
StandardOutput=, with one exception: if set to inherit the file
descriptor used for standard output is duplicated for standard error. This
setting defaults to the value set with DefaultStandardError= in
systemd-system.conf(5), which defaults to inherit.
TTYPath=
Sets the terminal device node to use if standard input,
output, or error are connected to a TTY (see above). Defaults to
/dev/console.
TTYReset=
Reset the terminal device specified with TTYPath=
before and after execution. Defaults to "no".
TTYVHangup=
Disconnect all clients which have opened the terminal
device specified with TTYPath= before and after execution. Defaults to
"no".
TTYVTDisallocate=
If the terminal device specified with TTYPath= is
a virtual console terminal, try to deallocate the TTY before and after
execution. This ensures that the screen and scrollback buffer is cleared.
Defaults to "no".
SyslogIdentifier=
Sets the process name to prefix log lines sent to syslog
or the kernel log buffer with. If not set, defaults to the process name of the
executed process. This option is only useful when StandardOutput= or
StandardError= are set to syslog or kmsg.
SyslogFacility=
Sets the syslog facility to use when logging to syslog.
One of kern, user, mail, daemon, auth,
syslog, lpr, news, uucp, cron,
authpriv, ftp, local0, local1, local2,
local3, local4, local5, local6 or local7.
See syslog(3) for details. This option is only useful when
StandardOutput= or StandardError= are set to syslog.
Defaults to daemon.
SyslogLevel=
Default syslog level to use when logging to syslog or the
kernel log buffer. One of emerg, alert, crit, err,
warning, notice, info, debug. See syslog(3)
for details. This option is only useful when StandardOutput= or
StandardError= are set to syslog or kmsg. Note that
individual lines output by the daemon might be prefixed with a different log
level which can be used to override the default log level specified here. The
interpretation of these prefixes may be disabled with
SyslogLevelPrefix=, see below. For details see sd-daemon(3).
Defaults to info.
SyslogLevelPrefix=
Takes a boolean argument. If true and
StandardOutput= or StandardError= are set to syslog,
kmsg or journal, log lines written by the executed process that
are prefixed with a log level will be passed on to syslog with this log level
set but the prefix removed. If set to false, the interpretation of these
prefixes is disabled and the logged lines are passed on as-is. For details
about this prefixing see sd-daemon(3). Defaults to true.
TimerSlackNSec=
Sets the timer slack in nanoseconds for the executed
processes. The timer slack controls the accuracy of wake-ups triggered by
timers. See prctl(2) for more information. Note that in contrast to
most other time span definitions this parameter takes an integer value in
nano-seconds if no unit is specified. The usual time units are understood
too.
LimitCPU=, LimitFSIZE=, LimitDATA=, LimitSTACK=,
LimitCORE=, LimitRSS=, LimitNOFILE=, LimitAS=,
LimitNPROC=, LimitMEMLOCK=, LimitLOCKS=,
LimitSIGPENDING=, LimitMSGQUEUE=, LimitNICE=,
LimitRTPRIO=, LimitRTTIME=
These settings control various resource limits for
executed processes. See setrlimit(2) for details. Use the string
infinity to configure no limit on a specific resource.
PAMName=
Sets the PAM service name to set up a session as. If set,
the executed process will be registered as a PAM session under the specified
service name. This is only useful in conjunction with the User=
setting. If not set, no PAM session will be opened for the executed processes.
See pam(8) for details.
CapabilityBoundingSet=
Controls which capabilities to include in the capability
bounding set for the executed process. See capabilities(7) for details.
Takes a whitespace-separated list of capability names as read by
cap_from_name(3), e.g. CAP_SYS_ADMIN, CAP_DAC_OVERRIDE,
CAP_SYS_PTRACE. Capabilities listed will be included in the bounding
set, all others are removed. If the list of capabilities is prefixed with
"~", all but the listed capabilities will be included, the effect of
the assignment inverted. Note that this option also affects the respective
capabilities in the effective, permitted and inheritable capability sets, on
top of what Capabilities= does. If this option is not used, the
capability bounding set is not modified on process execution, hence no limits
on the capabilities of the process are enforced. This option may appear more
than once in which case the bounding sets are merged. If the empty string is
assigned to this option, the bounding set is reset to the empty capability
set, and all prior settings have no effect. If set to "~" (without
any further argument), the bounding set is reset to the full set of available
capabilities, also undoing any previous settings.
SecureBits=
Controls the secure bits set for the executed process.
See capabilities(7) for details. Takes a list of strings:
keep-caps, keep-caps-locked, no-setuid-fixup,
no-setuid-fixup-locked, noroot and/or noroot-locked. This
option may appear more than once in which case the secure bits are ORed. If
the empty string is assigned to this option, the bits are reset to 0.
Capabilities=
Controls the capabilities(7) set for the executed
process. Take a capability string describing the effective, permitted and
inherited capability sets as documented in cap_from_text(3). Note that
these capability sets are usually influenced (and filtered) by the
capabilities attached to the executed file. Due to that
CapabilityBoundingSet= is probably the much more useful setting.
ReadWriteDirectories=, ReadOnlyDirectories=,
InaccessibleDirectories=
Sets up a new file system namespace for executed
processes. These options may be used to limit access a process might have to
the main file system hierarchy. Each setting takes a space-separated list of
absolute directory paths. Directories listed in ReadWriteDirectories=
are accessible from within the namespace with the same access rights as from
outside. Directories listed in ReadOnlyDirectories= are accessible for
reading only, writing will be refused even if the usual file access controls
would permit this. Directories listed in InaccessibleDirectories= will
be made inaccessible for processes inside the namespace. Note that restricting
access with these options does not extend to submounts of a directory that are
created later on. These options may be specified more than once in which case
all directories listed will have limited access from within the namespace. If
the empty string is assigned to this option, the specific list is reset, and
all prior assignments have no effect.
Paths in ReadOnlyDirectories= and InaccessibleDirectories= may be
prefixed with "-", in which case they will be ignored when they do
not exist. Note that using this setting will disconnect propagation of mounts
from the service to the host (propagation in the opposite direction continues
to work). This means that this setting may not be used for services which
shall be able to install mount points in the main mount namespace.
PrivateTmp=
Takes a boolean argument. If true, sets up a new file
system namespace for the executed processes and mounts private /tmp and
/var/tmp directories inside it that is not shared by processes outside of the
namespace. This is useful to secure access to temporary files of the process,
but makes sharing between processes via /tmp or /var/tmp impossible. If this
is enabled, all temporary files created by a service in these directories will
be removed after the service is stopped. Defaults to false. It is possible to
run two or more units within the same private /tmp and /var/tmp namespace by
using the JoinsNamespaceOf= directive, see systemd.unit(5) for
details. Note that using this setting will disconnect propagation of mounts
from the service to the host (propagation in the opposite direction continues
to work). This means that this setting may not be used for services which
shall be able to install mount points in the main mount namespace.
PrivateDevices=
Takes a boolean argument. If true, sets up a new /dev
namespace for the executed processes and only adds API pseudo devices such as
/dev/null, /dev/zero or /dev/random (as well as the pseudo TTY subsystem) to
it, but no physical devices such as /dev/sda. This is useful to securely turn
off physical device access by the executed process. Defaults to false.
Enabling this option will also remove CAP_MKNOD from the capability
bounding set for the unit (see above), and set DevicePolicy=closed (see
systemd.resource-control(5) for details). Note that using this setting
will disconnect propagation of mounts from the service to the host
(propagation in the opposite direction continues to work). This means that
this setting may not be used for services which shall be able to install mount
points in the main mount namespace.
PrivateNetwork=
Takes a boolean argument. If true, sets up a new network
namespace for the executed processes and configures only the loopback network
device "lo" inside it. No other network devices will be available to
the executed process. This is useful to securely turn off network access by
the executed process. Defaults to false. It is possible to run two or more
units within the same private network namespace by using the
JoinsNamespaceOf= directive, see systemd.unit(5) for details.
Note that this option will disconnect all socket families from the host, this
includes AF_NETLINK and AF_UNIX. The latter has the effect that AF_UNIX
sockets in the abstract socket namespace will become unavailable to the
processes (however, those located in the file system will continue to be
accessible).
ProtectSystem=
Takes a boolean argument or "full". If true,
mounts the /usr directory read-only for processes invoked by this unit. If set
to "full", the /etc directory is mounted read-only, too. This
setting ensures that any modification of the vendor supplied operating system
(and optionally its configuration) is prohibited for the service. It is
recommended to enable this setting for all long-running services, unless they
are involved with system updates or need to modify the operating system in
other ways. Note however that processes retaining the CAP_SYS_ADMIN capability
can undo the effect of this setting. This setting is hence particularly useful
for daemons which have this capability removed, for example with
CapabilityBoundingSet=. Defaults to off.
ProtectHome=
Takes a boolean argument or "read-only". If
true, the directories /home and /run/user are made inaccessible and empty for
processes invoked by this unit. If set to "read-only", the two
directores are made read-only instead. It is recommended to enable this
setting for all long-running services (in particular network-facing ones), to
ensure they cannot get access to private user data, unless the services
actually require access to the user's private data. Note however that
processes retaining the CAP_SYS_ADMIN capability can undo the effect of this
setting. This setting is hence particularly useful for daemons which have this
capability removed, for example with CapabilityBoundingSet=. Defaults
to off.
MountFlags=
Takes a mount propagation flag: shared,
slave or private, which control whether mounts in the file
system namespace set up for this unit's processes will receive or propagate
mounts or unmounts. See mount(2) for details. Defaults to
shared. Use shared to ensure that mounts and unmounts are
propagated from the host to the container and vice versa. Use slave to
run processes so that none of their mounts and unmounts will propagate to the
host. Use private to also ensure that no mounts and unmounts from the
host will propagate into the unit processes' namespace. Note that slave
means that file systems mounted on the host might stay mounted continously in
the unit's namespace, and thus keep the device busy. Note that the file system
namespace related options ( PrivateTmp=, PrivateDevices=,
ReadOnlySystem=, ProtectedHome=, ReadOnlyDirectories=,
InaccessibleDirectories= and ReadWriteDirectories=) require that
mount and unmount propagation from the unit's file system namespace is
disabled, and hence downgrade shared to slave.
UtmpIdentifier=
Takes a four character identifier string for an utmp/wtmp
entry for this service. This should only be set for services such as
getty implementations where utmp/wtmp entries must be created and
cleared before and after execution. If the configured string is longer than
four characters, it is truncated and the terminal four characters are used.
This setting interprets %I style string replacements. This setting is unset by
default, i.e. no utmp/wtmp entries are created or cleaned up for this
service.
SELinuxContext=
Set the SELinux security context of the executed process.
If set, this will override the automated domain transition. However, the
policy still needs to autorize the transition. This directive is ignored if
SELinux is disabled. If prefixed by "-", all errors will be ignored.
See setexeccon(3) for details.
AppArmorProfile=
Takes a profile name as argument. The process executed by
the unit will switch to this profile when started. Profiles must already be
loaded in the kernel, or the unit will fail. This result in a non operation if
AppArmor is not enabled. If prefixed by "-", all errors will be
ignored.
IgnoreSIGPIPE=
Takes a boolean argument. If true, causes SIGPIPE
to be ignored in the executed process. Defaults to true because SIGPIPE
generally is useful only in shell pipelines.
NoNewPrivileges=
Takes a boolean argument. If true, ensures that the
service process and all its children can never gain new privileges. This
option is more powerful than the respective secure bits flags (see above), as
it also prohibits UID changes of any kind. This is the simplest, most
effective way to ensure that a process and its children can never elevate
privileges again.
SystemCallFilter=
Takes a space-separated list of system call names. If
this setting is used, all system calls executed by the unit processes except
for the listed ones will result in immediate process termination with the
SIGSYS signal (whitelisting). If the first character of the list is
"~", the effect is inverted: only the listed system calls will
result in immediate process termination (blacklisting). If running in user
mode and this option is used, NoNewPrivileges=yes is implied. This
feature makes use of the Secure Computing Mode 2 interfaces of the kernel
('seccomp filtering') and is useful for enforcing a minimal sandboxing
environment. Note that the execve, rt_sigreturn,
sigreturn, exit_group, exit system calls are implicitly
whitelisted and do not need to be listed explicitly. This option may be
specified more than once in which case the filter masks are merged. If the
empty string is assigned, the filter is reset, all prior assignments will have
no effect.
If you specify both types of this option (i.e. whitelisting and blacklisting),
the first encountered will take precedence and will dictate the default action
(termination or approval of a system call). Then the next occurrences of this
option will add or delete the listed system calls from the set of the filtered
system calls, depending of its type and the default action. (For example, if
you have started with a whitelisting of read and write, and
right after it add a blacklisting of write, then write will be
removed from the set.)
SystemCallErrorNumber=
Takes an "errno" error number name to return
when the system call filter configured with SystemCallFilter= is
triggered, instead of terminating the process immediately. Takes an error name
such as EPERM, EACCES or EUCLEAN. When this setting is
not used, or when the empty string is assigned, the process will be terminated
immediately when the filter is triggered.
SystemCallArchitectures=
Takes a space separated list of architecture identifiers
to include in the system call filter. The known architecture identifiers are
x86, x86-64, x32, arm as well as the special
identifier native. Only system calls of the specified architectures
will be permitted to processes of this unit. This is an effective way to
disable compatibility with non-native architectures for processes, for example
to prohibit execution of 32-bit x86 binaries on 64-bit x86-64 systems. The
special native identifier implicitly maps to the native architecture of
the system (or more strictly: to the architecture the system manager is
compiled for). If running in user mode and this option is used,
NoNewPrivileges=yes is implied. Note that setting this option to a
non-empty list implies that native is included too. By default, this
option is set to the empty list, i.e. no architecture system call filtering is
applied.
RestrictAddressFamilies=
Restricts the set of socket address families accessible
to the processes of this unit. Takes a space-separated list of address family
names to whitelist, such as AF_UNIX, AF_INET or AF_INET6.
When prefixed with ~ the listed address families will be applied as
blacklist, otherwise as whitelist. Note that this restricts access to the
socket(2) system call only. Sockets passed into the process by other
means (for example, by using socket activation with socket units, see
systemd.socket(5)) are unaffected. Also, sockets created with
socketpair() (which creates connected AF_UNIX sockets only) are
unaffected. Note that this option has no effect on 32-bit x86 and is ignored
(but works correctly on x86-64). If running in user mode and this option is
used, NoNewPrivileges=yes is implied. By default, no restriction
applies, all address families are accessible to processes. If assigned the
empty string, any previous list changes are undone.
Use this option to limit exposure of processes to remote systems, in particular
via exotic network protocols. Note that in most cases, the local
AF_UNIX address family should be included in the configured whitelist
as it is frequently used for local communication, including for
syslog(2) logging.
Personality=
Controls which kernel architecture uname(2) shall
report, when invoked by unit processes. Takes one of x86 and
x86-64. This is useful when running 32-bit services on a 64-bit host
system. If not specified, the personality is left unmodified and thus reflects
the personality of the host system's kernel.
RuntimeDirectory=, RuntimeDirectoryMode=
Takes a list of directory names. If set, one or more
directories by the specified names will be created below /run (for system
services) or below $XDG_RUNTIME_DIR (for user services) when the unit
is started, and removed when the unit is stopped. The directories will have
the access mode specified in RuntimeDirectoryMode=, and will be owned
by the user and group specified in User= and Group=. Use this to
manage one or more runtime directories of the unit and bind their lifetime to
the daemon runtime. The specified directory names must be relative, and may
not include a "/", i.e. must refer to simple directories to create
or remove. This is particularly useful for unprivileged daemons that cannot
create runtime directories in /run due to lack of privileges, and to make sure
the runtime directory is cleaned up automatically after use. For runtime
directories that require more complex or different configuration or lifetime
guarantees, please consider using tmpfiles.d(5).
ENVIRONMENT VARIABLES IN SPAWNED PROCESSES¶
Processes started by the system are executed in a clean environment in which select variables listed below are set. System processes started by systemd do not inherit variables from PID 1, but processes started by user systemd instances inherit all environment variables from the user systemd instance. $PATHColon-separated list of directiories to use when
launching executables. Systemd uses a fixed value of
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin.
$LANG
Locale. Can be set in locale.conf(5) or on the
kernel command line (see systemd(1) and
kernel-command-line(7)).
$USER, $LOGNAME, $HOME, $SHELL
User name (twice), home directory, and the login shell.
The variables are set for the units that have User= set, which includes
user systemd instances. See passwd(5).
$XDG_RUNTIME_DIR
The directory for volatile state. Set for the user
systemd instance, and also in user sessions. See
pam_systemd(8).
$XDG_SESSION_ID, $XDG_SEAT, $XDG_VTNR
The identifier of the session, the seat name, and virtual
terminal of the session. Set by pam_systemd(8) for login sessions.
$XDG_SEAT and $XDG_VTNR will only be set when attached to a seat
and a tty.
$MAINPID
The PID of the units main process if it is known. This is
only set for control processes as invoked by ExecReload= and
similar.
$MANAGERPID
The PID of the user systemd instance, set for
processes spawned by it.
$LISTEN_FDS, $LISTEN_PID
Information about file descriptors passed to a service
for socket activation. See sd_listen_fds(3).
$TERM
Terminal type, set only for units connected to a terminal
( StandardInput=tty, StandardOutput=tty, or
StandardError=tty). See termcap(5).
Additional variables may be configured by the following means: for processes
spawned in specific units, use the Environment= and
EnvironmentFile= options above; to specify variables globally, use
DefaultEnvironment= (see systemd-system.conf(5)) or the kernel
option systemd.setenv= (see systemd(1)). Additional variables
may also be set through PAM, cf. pam_env(8).
SEE ALSO¶
systemd(1), systemctl(1), journalctl(8), systemd.unit(5), systemd.service(5), systemd.socket(5), systemd.swap(5), systemd.mount(5), systemd.kill(5), systemd.resource-control(5), systemd.directives(7), tmpfiles.d(5), exec(3)NOTES¶
- 1.
- proc.txt
systemd 215 |