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NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | EXIT STATUS | EXAMPLES | ENVIRONMENT | SEE ALSO | COLOPHON |
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LOGINCTL(1) loginctl LOGINCTL(1)
loginctl - Control the systemd login manager
loginctl [OPTIONS...] {COMMAND} [NAME...]
loginctl may be used to introspect and control the state of the
systemd(1) login manager systemd-logind.service(8).
The following commands are understood:
Session Commands
list-sessions
List current sessions. The JSON format output can be toggled
using --json= or -j option.
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. The JSON format output can be
toggled using --json= or -j option.
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.
enable-linger [USER...], disable-linger [USER...]
Enable/disable user lingering for one or more users. If
enabled for a specific user, a user manager is spawned for the
user at boot and kept around after logouts. This allows users
who are not logged in to run long-running services. Takes one
or more user names or numeric UIDs as argument. If no argument
is specified, enables/disables lingering for the user of the
session of the caller.
See also KillUserProcesses= setting in logind.conf(5).
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. The JSON
format output can be toggled using --json= or -j option.
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.
The following options are understood:
-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.
-n, --lines=
When used with user-status and session-status, controls the
number of journal lines to show, counting from the most recent
ones. Takes a positive integer argument. Defaults to 10.
Added in version 219.
-o, --output=
When used with user-status and session-status, controls the
formatting of the journal entries that are shown. For the
available choices, see journalctl(1). Defaults to "short".
Added in version 219.
-H, --host=
Execute the operation remotely. Specify a hostname, or a
username and hostname separated by "@", to connect to. The
hostname may optionally be suffixed by a port ssh is listening
on, separated by ":", and then a container name, separated by
"/", which connects directly to a specific container on the
specified host. This will use SSH to talk to the remote
machine manager instance. Container names may be enumerated
with machinectl -H HOST. Put IPv6 addresses in brackets.
-M, --machine=
Execute operation on a local container. Specify a container
name to connect to, optionally prefixed by a user name to
connect as and a separating "@" character. If the special
string ".host" is used in place of the container name, a
connection to the local system is made (which is useful to
connect to a specific user's user bus: "--user
--machine=lennart@.host"). If the "@" syntax is not used, the
connection is made as root user. If the "@" syntax is used
either the left hand side or the right hand side may be
omitted (but not both) in which case the local user name and
".host" are implied.
--no-ask-password
Do not query the user for authentication for privileged
operations.
--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.
--json=MODE
Shows output formatted as JSON. Expects one of "short" (for
the shortest possible output without any redundant whitespace
or line breaks), "pretty" (for a pretty version of the same,
with indentation and line breaks) or "off" (to turn off JSON
output, the default).
-j
Equivalent to --json=pretty if running on a terminal, and
--json=short otherwise.
-h, --help
Print a short help text and exit.
--version
Print a short version string and exit.
On success, 0 is returned, a non-zero failure code otherwise.
Example 1. Querying user status
$ loginctl user-status
fatima (1005)
Since: Sat 2016-04-09 14:23:31 EDT; 54min ago
State: active
Sessions: 5 *3
Unit: user-1005.slice
├─user@1005.service
...
├─session-3.scope
...
└─session-5.scope
├─3473 login -- fatima
└─3515 -zsh
Apr 09 14:40:30 laptop login[2325]: pam_unix(login:session):
session opened for user fatima by LOGIN(uid=0)
Apr 09 14:40:30 laptop login[2325]: LOGIN ON tty3 BY fatima
There are two sessions, 3 and 5. Session 3 is a graphical session,
marked with a star. The tree of processing including the two
corresponding scope units and the user manager unit are shown.
$SYSTEMD_LOG_LEVEL
The maximum log level of emitted messages (messages with a
higher log level, i.e. less important ones, will be
suppressed). Takes a comma-separated list of values. A value
may be 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. Each value may optionally be prefixed with one of
console, syslog, kmsg or journal followed by a colon to set
the maximum log level for that specific log target (e.g.
SYSTEMD_LOG_LEVEL=debug,console:info specifies to log at debug
level except when logging to the console which should be at
info level). Note that the global maximum log level takes
priority over any per target maximum log levels.
$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, systemd 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.
Note that setting the regular $LESS environment variable has
no effect for less invocations by systemd tools.
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).
Note that setting the regular $LESSCHARSET environment
variable has no effect for less invocations by systemd tools.
$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.
systemd(1), systemctl(1), systemd-logind.service(8),
logind.conf(5)
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
⟨http://www.freedesktop.org/wiki/Software/systemd/#bugreports⟩.
This page was obtained from the project's upstream Git repository
⟨https://github.com/systemd/systemd.git⟩ on 2025-02-02. (At that
time, the date of the most recent commit that was found in the
repository was 2025-02-02.) 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
man-pages@man7.org
systemd 258~devel LOGINCTL(1)
Pages that refer to this page: systemctl(1), w(1), logind.conf(5), org.freedesktop.login1(5), systemd.directives(7), systemd.index(7), pam_systemd(8), systemd-logind.service(8), systemd-machined.service(8)
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HTML rendering created 2025-02-02 by Michael Kerrisk, author of The Linux Programming Interface. For details of in-depth Linux/UNIX system programming training courses that I teach, look here. Hosting by jambit GmbH. |
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