loginctl(1)
NAME
loginctl - Control the systemd login manager
SYNOPSIS
loginctl [OPTIONS...] {COMMAND} [NAME...]
DESCRIPTION
loginctl may be used to introspect and control the state of the systemd(1) login manager systemd-logind.service(8).
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 printing properties with show, only print the value, and skip
the property name and "=".
-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.
--kill-who=
When used with kill-session, choose which processes to kill. Must
be 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.
-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.
-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.
-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".
-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 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.
-M, --machine=
Execute operation on a local container. Specify a container name to
connect to.
--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.
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.
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.
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.
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.
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.
lock-sessions, unlock-sessions
Activates/deactivates the screen lock on all current sessions
supporting it.
terminate-session ID...
Terminates a session. This kills all processes of the session and
deallocates all resources attached to the session.
kill-session ID...
Send a signal to one or more processes of the session. Use
--kill-who= to select which process to kill. Use --signal= to
select the signal to send.
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 of the caller's user is shown.
This function is intended to generate human-readable output. If you
are looking for computer-parsable output, use show-user instead.
Users may be specified by their usernames or numeric user IDs.
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.
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).
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.
kill-user USER...
Send a signal to all processes of a user. Use --signal= to select
the signal to send.
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.
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.
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.
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.
EXIT STATUS
On success, 0 is returned, a non-zero failure code otherwise.
EXAMPLES
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.
ENVIRONMENT
$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.
$SYSTEMD_LESS
Override the options passed to less (by default "FRSXMK").
$SYSTEMD_LESSCHARSET
Override the charset passed to less (by default "utf-8", if the
invoking terminal is determined to be UTF-8 compatible).
SEE ALSO
systemd(1), systemctl(1), systemd-logind.service(8), logind.conf(5)
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