DOKK / manpages / debian 10 / elogind / loginctl.1.en
LOGINCTL(1) loginctl LOGINCTL(1)

loginctl - Control the elogind login manager

loginctl [OPTIONS...] {COMMAND} [NAME...]

/lib/elogind/system-shutdown

/lib/elogind/system-sleep

loginctl may be used to introspect and control the state of the

elogind(8) login manager

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 "=".

-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.

-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.

The following commands are understood:

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.

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.

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.

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.

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.

poweroff

Print a wall message to all users, shut down and power-off the system.

reboot [arg]

Print a wall message to all users, shut down and reboot the system.

If the optional argument arg is given, it will be passed as the optional argument to the reboot(2) system call. The value is architecture and firmware specific. As an example, "recovery" might be used to trigger system recovery, and "fota" might be used to trigger a “firmware over the air” update.

suspend

Suspend the system.

hibernate

Hibernate the system.

hybrid-sleep

Hibernate and suspend the system.

suspend-then-hibernate

Suspend the system, wake after a period of time and put it into hibernate

Immediately before entering system suspend and/or hibernation elogind will run all executables in [/usr]/lib/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.

Note that scripts or binaries dropped in [/usr]/lib/elogind/system-sleep/ are intended for local use only and should be considered hacks. If applications want to react to system suspend/hibernation and resume, they should rather use the Inhibitor interface[1].

Immediately before executing the actual system poweroff/reboot elogind will run all executables in [/usr]/lib/elogind/system-shutdown/ and pass one arguments to them, either "poweroff" or "reboot", depending on the chosen action. All executables in this directory are executed sequentially, and execution of the action is not continued before all executables finished.

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.

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

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_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).

elogind(8),

logind.conf(5)

1.
Inhibitor interface
https://www.freedesktop.org/wiki/Software/systemd/inhibit
elogind 239.3