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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:
--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.
-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-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 2024-06-14. (At that
time, the date of the most recent commit that was found in the
repository was 2024-06-13.) 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 257~devel LOGINCTL(1)
Pages that refer to this page: systemctl(1), logind.conf(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 2024-06-26 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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