Ubuntu Manpage: systemd-inhibit - Execute a program with an inhibition lock taken

Provided by: systemd_256.5-2ubuntu3.1_amd64

NAME

       systemd-inhibit - Execute a program with an inhibition lock taken

SYNOPSIS

       systemd-inhibit [OPTIONS...] [COMMAND] [ARGUMENTS...]

       systemd-inhibit [OPTIONS...] [--list]

DESCRIPTION

       systemd-inhibit may be used to execute a program with a shutdown, sleep, or idle inhibitor
       lock taken. The lock will be acquired before the specified command line is executed and
       released afterwards.

       Inhibitor locks may be used to block or delay system sleep and shutdown requests from the
       user, as well as automatic idle handling of the OS. This is useful to avoid system
       suspends while an optical disc is being recorded, or similar operations that should not be
       interrupted.

       For more information see Inhibitor Locks[1].

OPTIONS

The following options are understood:

--what=
Takes a colon-separated list of one or more operations to inhibit: "shutdown",
"sleep", "idle", "handle-power-key", "handle-suspend-key", "handle-hibernate-key",
"handle-lid-switch", for inhibiting reboot/power-off/halt/kexec/soft-reboot,
suspending/hibernating, the automatic idle detection, or the low-level handling of the
power/sleep key and the lid switch, respectively. If omitted, defaults to
"idle:sleep:shutdown".

--who=
Takes a short, human-readable descriptive string for the program taking the lock. If
not passed, defaults to the command line string.

--why=
Takes a short, human-readable descriptive string for the reason for taking the lock.
Defaults to "Unknown reason".

--mode=
Takes either "block" or "delay" and describes how the lock is applied. If "block" is
used (the default), the lock prohibits any of the requested operations without time
limit, and only privileged users may override it. If "delay" is used, the lock can
only delay the requested operations for a limited time. If the time elapses, the lock
is ignored and the operation executed. The time limit may be specified in
logind.conf(5). Note that "delay" is only available for "sleep" and "shutdown".

--list
Lists all active inhibition locks instead of acquiring one.

--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

       Returns the exit status of the executed program.

EXAMPLE

           # systemd-inhibit wodim foobar.iso

       This burns the ISO image foobar.iso on a CD using wodim(1), and inhibits system sleeping,
       shutdown and idle while doing so.

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). 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.

NOTES

        1. Inhibitor Locks
           https://systemd.io/INHIBITOR_LOCKS