NAME¶
loginctl - Control the elogind login manager
SYNOPSIS¶
loginctl [OPTIONS...] {COMMAND} [NAME...]
/lib/elogind/system-shutdown
/lib/elogind/system-sleep
DESCRIPTION¶
loginctl may be used to introspect and control the state of
the
elogind(8) login manager
COMMANDS¶
The following commands are understood:
Session Commands¶
list-sessions
List current sessions.
session-status [ID...]
Show terse runtime status information about one or more
sessions, followed by the most recent log data from the journal. Takes one or
more session identifiers as parameters. If no session identifiers are passed,
the status of the caller's session is shown. This function is intended to
generate human-readable output. If you are looking for computer-parsable
output, use
show-session instead.
Added in version 233.
show-session [ID...]
Show properties of one or more sessions or the manager
itself. If no argument is specified, properties of the manager will be shown.
If a session ID is specified, properties of the session are shown. Specially,
if the given ID is "self", the session to which the
loginctl
process belongs is used. If "auto", the current session is used as
with "self" if exists, and falls back to the current user's
graphical session. By default, empty properties are suppressed. Use
--all to show those too. To select specific properties to show, use
--property=. This command is intended to be used whenever
computer-parsable output is required. Use
session-status if you are
looking for formatted human-readable output.
Added in version 233.
activate [ID]
Activate a session. This brings a session into the
foreground if another session is currently in the foreground on the respective
seat. Takes a session identifier as argument. If no argument is specified, the
session of the caller is put into foreground.
Added in version 219.
lock-session [ID...], unlock-session
[ID...]
Activates/deactivates the screen lock on one or more
sessions, if the session supports it. Takes one or more session identifiers as
arguments. If no argument is specified, the session of the caller is
locked/unlocked.
Added in version 233.
lock-sessions, unlock-sessions
Activates/deactivates the screen lock on all current
sessions supporting it.
Added in version 188.
terminate-session ID...
Terminates a session. This kills all processes of the
session and deallocates all resources attached to the session. If the argument
is specified as empty string the session invoking the command is terminated.
Added in version 233.
kill-session ID...
Send a signal to one or more processes of the session.
Use
--kill-whom= to select which process to kill. Use
--signal=
to select the signal to send. If the argument is specified as empty string the
signal is sent to the session invoking the command.
Added in version 233.
User Commands¶
list-users
List currently logged in users.
user-status [USER...]
Show terse runtime status information about one or more
logged in users, followed by the most recent log data from the journal. Takes
one or more user names or numeric user IDs as parameters. If no parameters are
passed, the status is shown for the user of the session of the caller. This
function is intended to generate human-readable output. If you are looking for
computer-parsable output, use
show-user instead.
Added in version 233.
show-user [USER...]
Show properties of one or more users or the manager
itself. If no argument is specified, properties of the manager will be shown.
If a user is specified, properties of the user are shown. By default, empty
properties are suppressed. Use
--all to show those too. To select
specific properties to show, use
--property=. This command is intended
to be used whenever computer-parsable output is required. Use
user-status if you are looking for formatted human-readable output.
Added in version 233.
terminate-user USER...
Terminates all sessions of a user. This kills all
processes of all sessions of the user and deallocates all runtime resources
attached to the user. If the argument is specified as empty string the
sessions of the user invoking the command are terminated.
Added in version 233.
kill-user USER...
Send a signal to all processes of a user. Use
--signal= to select the signal to send. If the argument is specified as
empty string the signal is sent to the sessions of the user invoking the
command.
Added in version 233.
Seat Commands¶
list-seats
List currently available seats on the local system.
seat-status [NAME...]
Show terse runtime status information about one or more
seats. Takes one or more seat names as parameters. If no seat names are passed
the status of the caller's session's seat is shown. This function is intended
to generate human-readable output. If you are looking for computer-parsable
output, use
show-seat instead.
Added in version 233.
show-seat [NAME...]
Show properties of one or more seats or the manager
itself. If no argument is specified, properties of the manager will be shown.
If a seat is specified, properties of the seat are shown. By default, empty
properties are suppressed. Use
--all to show those too. To select
specific properties to show, use
--property=. This command is intended
to be used whenever computer-parsable output is required. Use
seat-status if you are looking for formatted human-readable output.
Added in version 233.
attach NAME DEVICE...
Persistently attach one or more devices to a seat. The
devices should be specified via device paths in the /sys/ file system. To
create a new seat, attach at least one graphics card to a previously unused
seat name. Seat names may consist only of a–z, A–Z, 0–9,
"-" and "_" and must be prefixed with "seat". To
drop assignment of a device to a specific seat, just reassign it to a
different seat, or use
flush-devices.
Added in version 233.
flush-devices
Removes all device assignments previously created with
attach. After this call, only automatically generated seats will
remain, and all seat hardware is assigned to them.
terminate-seat NAME...
Terminates all sessions on a seat. This kills all
processes of all sessions on the seat and deallocates all runtime resources
attached to them.
Added in version 233.
System Commands¶
reload
Reload the elogind configuration. While the daemon is
being reloaded, all sockets elogind listens on behalf of user configuration
will stay accessible.
poweroff
Shut down and power-off the system. This is mostly
equivalent to shutdown -h. This command is asynchronous; it will return
after the power-off operation is enqueued, without waiting for it to
complete.
reboot [--firmware-setup]
Shut down and reboot the system. This is mostly
equivalent to
shutdown -r. This command is asynchronous; it will return
after the reboot operation is enqueued, without waiting for it to complete.
If the optional argument --firmware-setup is given,
indicate to the system's firmware to reboot into the firmware setup
interface. Note that this functionality is not available on all systems.
suspend
Suspend the system. This will tell all processes
registered via dbus to prepare for suspension. This command is asynchronous,
and will return after the suspend operation is successfully enqueued. It will
not wait for the suspend/resume cycle to complete.
hibernate
Hibernate the system. This will tell all processes
registered via dbus to prepare for hibernation. This command is asynchronous,
and will return after the hibernation operation is successfully enqueued. It
will not wait for the hibernate/thaw cycle to complete.
hybrid-sleep
Hibernate and suspend the system. This will tell all
processes registered via dbus to prepare for hybrid-sleep. This command is
asynchronous, and will return after the hybrid sleep operation is successfully
enqueued. It will not wait for the sleep/wake-up cycle to complete.
suspend-then-hibernate
Suspend the system and hibernate it after the delay
specified in logind.conf. This will tell all processes registered via dbus to
prepare for suspend-then-hibernate. This command is asynchronous, and will
return after the hybrid sleep operation is successfully enqueued. It will not
wait for the sleep/wake-up or hibernate/thaw cycle to complete.
Hook directories¶
[/usr]/lib[64]/elogind/system-sleep/,
/etc/elogind/system-sleep/
Immediately before entering system suspend and/or
hibernation elogind will run all executables in
[/usr]/lib[64]/elogind/system-sleep/ and
/etc/elogind/system-sleep/ and pass two arguments to them. The first
argument will be "pre", the second either "suspend",
"hibernate", "hybrid-sleep", or
"suspend-then-hibernate", depending on the chosen action.
Immediately after leaving system suspend and/or hibernation the same
executables are run, but the first argument is now "post". All
executables in this directory are executed sequentially, and execution of the
action is not continued until all executables have finished.
[/usr]/lib[64]/elogind/system-shutdown/,
/etc/elogind/system-shutdown/
Immediately before rebooting or powering the system off,
elogind will run all executables in
[/usr]/lib[64]/elogind/system-shutdown/ and
/etc/elogind/system-shutdown/ and pass one argument to them. The
argument will either be "poweroff" or "reboot", depending
on the chosen action.
AllowPowerOffInterrupts, AllowSuspendInterrupts
Whether the executables in these directories run
successfully or not is of no concern to elogind. If you want the scripts to
cause the action to be cancelled if one fails, you can set
"AllowPowerOffInterrupts" and/or "AllowSuspendInterrupts"
to "yes" in /etc/elogind/logind.conf. For this to work the
executables in question must print an error message to "STDOUT" that
begins with either of these keywords: "CANCELLED",
"CRITICAL", "ERROR" or "FAILED". If you want any
of these words in a message without causing the action to be cancelled, just
re-arrange the sentence in question so that the keyword is not the first
word.
BroadcastPowerOffInterrupts,
BroadcastSuspendInterrupts
By default an interrupt of a power off or a suspend is
broadcasted. If you do not whish these broadcasts to happen, change
"BroadcastPowerOffInterrupts" and/or
"BroadcastSuspendInterrupts" to "no" in
/etc/elogind/logind.conf.
Note that scripts or binaries dropped in any of the hook
directories are intended for local use only and should be considered hacks.
If applications want to react to these system commands, they should rather
use the Inhibitor interface[1].
OPTIONS¶
The following options are understood:
--no-ask-password
Do not query the user for authentication for privileged
operations.
-p, --property=
When showing session/user/seat properties, limit display
to certain properties as specified as argument. If not specified, all set
properties are shown. The argument should be a property name, such as
"Sessions". If specified more than once, all properties with the
specified names are shown.
--value
When showing session/user/seat properties, only print the
value, and skip the property name and "=".
Added in version 230.
-a, --all
When showing session/user/seat properties, show all
properties regardless of whether they are set or not.
-l, --full
Do not ellipsize process tree entries.
Added in version 198.
--kill-whom=
When used with
kill-session, choose which
processes to kill. Takes one of "leader" or "all", to
select whether to kill only the leader process of the session or all processes
of the session. If omitted, defaults to
all.
Added in version 252.
-s, --signal=
When used with
kill-session or
kill-user,
choose which signal to send to selected processes. Must be one of the well
known signal specifiers, such as
SIGTERM,
SIGINT or
SIGSTOP. If omitted, defaults to
SIGTERM.
The special value "help" will list the known values and
the program will exit immediately, and the special value "list"
will list known values along with the numerical signal numbers and the
program will exit immediately.
-o, --output=
When used with
user-status and
session-status, controls the formatting of the journal entries that are
shown. Defaults to "short".
Added in version 219.
-c
Cancel a pending shutdown or reboot.
-i, --ignore-inhibitors
When system shutdown or a sleep state is requested,
ignore inhibitor locks. Applications can establish inhibitor locks to avoid
that certain important operations (such as CD burning or suchlike) are
interrupted by system shutdown or a sleep state. Any user may take these locks
and privileged users may override these locks. If any locks are taken,
shutdown and sleep state requests will normally fail (unless privileged) and a
list of active locks is printed. However, if --ignore-inhibitors is
specified, the established locks are ignored and not shown, and the operation
attempted anyway, possibly requiring additional privileges.
--dry-run
Just print what would be done. Currently supported by
verbs halt, poweroff, reboot, suspend,
hibernate, hybrid-sleep, and
suspend-then-hibernate.
--no-wall
Do not send wall messages before halt, power-off and
reboot.
--no-pager
Do not pipe output into a pager.
--no-legend
Do not print the legend, i.e. column headers and the
footer with hints.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
EXIT STATUS¶
On success, 0 is returned, a non-zero failure code otherwise.
EXAMPLES¶
Example 1. Querying user status
$ loginctl user-status
sed (1004)
Since: Wed 2020-01-29 20:32:00 CET; 3 days ago
State: active
Sessions: 3 *2
Linger: no
Unit: user-1004.slice
There are two sessions, 2 and 3. The session 2 is a graphical
session, marked with a star. Uptime, state, lingering state und the user
unit are shown. The user unit is an artificial construct, elogind does not
really support systemd units and slices.
ENVIRONMENT¶
$SYSTEMD_LOG_LEVEL
The maximum log level of emitted messages (messages with
a higher log level, i.e. less important ones, will be suppressed). Either one
of (in order of decreasing importance)
emerg,
alert,
crit,
err,
warning,
notice,
info,
debug, or an integer in the range 0...7. See
syslog(3) for more
information.
$SYSTEMD_LOG_COLOR
A boolean. If true, messages written to the tty will be
colored according to priority.
This setting is only useful when messages are written directly to
the terminal, because journalctl(1) and other tools that display logs
will color messages based on the log level on their own.
$SYSTEMD_LOG_TIME
A boolean. If true, console log messages will be prefixed
with a timestamp.
This setting is only useful when messages are written directly to
the terminal or a file, because journalctl(1) and other tools that
display logs will attach timestamps based on the entry metadata on their
own.
$SYSTEMD_LOG_LOCATION
A boolean. If true, messages will be prefixed with a
filename and line number in the source code where the message originates.
Note that the log location is often attached as metadata to
journal entries anyway. Including it directly in the message text can
nevertheless be convenient when debugging programs.
$SYSTEMD_LOG_TID
A boolean. If true, messages will be prefixed with the
current numerical thread ID (TID).
Note that the this information is attached as metadata to journal
entries anyway. Including it directly in the message text can nevertheless
be convenient when debugging programs.
$SYSTEMD_LOG_TARGET
The destination for log messages. One of
console
(log to the attached tty),
console-prefixed (log to the attached tty
but with prefixes encoding the log level and "facility", see
syslog(3),
kmsg (log to the kernel circular log buffer),
journal (log to the journal),
journal-or-kmsg (log to the
journal if available, and to kmsg otherwise),
auto (determine the
appropriate log target automatically, the default),
null (disable log
output).
$SYSTEMD_LOG_RATELIMIT_KMSG
Whether to ratelimit kmsg or not. Takes a boolean.
Defaults to "true". If disabled, elogind will not ratelimit messages
written to kmsg.
$SYSTEMD_PAGER
Pager to use when
--no-pager is not given;
overrides
$PAGER. If neither
$SYSTEMD_PAGER nor
$PAGER
are set, a set of well-known pager implementations are tried in turn,
including
less(1) and
more(1), until one is found. If no pager
implementation is discovered no pager is invoked. Setting this environment
variable to an empty string or the value "cat" is equivalent to
passing
--no-pager.
Note: if $SYSTEMD_PAGERSECURE is not set,
$SYSTEMD_PAGER (as well as $PAGER) will be silently
ignored.
$SYSTEMD_LESS
Override the options passed to
less (by default
"FRSXMK").
Users might want to change two options in particular:
K
This option instructs the pager to exit immediately when
Ctrl+C is pressed. To allow
less to handle Ctrl+C itself to switch back
to the pager command prompt, unset this option.
If the value of $SYSTEMD_LESS does not include
"K", and the pager that is invoked is less, Ctrl+C will be
ignored by the executable, and needs to be handled by the pager.
X
This option instructs the pager to not send termcap
initialization and deinitialization strings to the terminal. It is set by
default to allow command output to remain visible in the terminal even after
the pager exits. Nevertheless, this prevents some pager functionality from
working, in particular paged output cannot be scrolled with the mouse.
See less(1) for more discussion.
$SYSTEMD_LESSCHARSET
Override the charset passed to less (by default
"utf-8", if the invoking terminal is determined to be UTF-8
compatible).
$SYSTEMD_PAGERSECURE
Takes a boolean argument. When true, the
"secure" mode of the pager is enabled; if false, disabled. If
$SYSTEMD_PAGERSECURE is not set at all, secure mode is enabled if the
effective UID is not the same as the owner of the login session, see
geteuid(2) and
sd_pid_get_owner_uid(3). In secure mode,
LESSSECURE=1 will be set when invoking the pager, and the pager shall
disable commands that open or create new files or start new subprocesses. When
$SYSTEMD_PAGERSECURE is not set at all, pagers which are not known to
implement secure mode will not be used. (Currently only
less(1)
implements secure mode.)
Note: when commands are invoked with elevated privileges, for
example under sudo(8) or pkexec(1), care must be taken to
ensure that unintended interactive features are not enabled.
"Secure" mode for the pager may be enabled automatically as
describe above. Setting SYSTEMD_PAGERSECURE=0 or not removing it from
the inherited environment allows the user to invoke arbitrary commands. Note
that if the $SYSTEMD_PAGER or $PAGER variables are to be
honoured, $SYSTEMD_PAGERSECURE must be set too. It might be
reasonable to completely disable the pager using --no-pager
instead.
$SYSTEMD_COLORS
Takes a boolean argument. When true, systemd and
related utilities will use colors in their output, otherwise the output will
be monochrome. Additionally, the variable can take one of the following
special values: "16", "256" to restrict the use of colors
to the base 16 or 256 ANSI colors, respectively. This can be specified to
override the automatic decision based on $TERM and what the console is
connected to.
$SYSTEMD_URLIFY
The value must be a boolean. Controls whether clickable
links should be generated in the output for terminal emulators supporting
this. This can be specified to override the decision that systemd makes
based on $TERM and other conditions.
NOTES¶
- 1.
- Inhibitor interface
