systemd-run

SYSTEMD-RUN(1) systemd-run SYSTEMD-RUN(1)

NAME
systemd-run - Run programs in transient scope units, service units, or
path-, socket-, or timer-triggered service units

SYNOPSIS
systemd-run [OPTIONS...] COMMAND [ARGS...]

systemd-run [OPTIONS...] [PATH OPTIONS...] {COMMAND} [ARGS...]

systemd-run [OPTIONS...] [SOCKET OPTIONS...] {COMMAND} [ARGS...]

systemd-run [OPTIONS...] [TIMER OPTIONS...] {COMMAND} [ARGS...]

DESCRIPTION
systemd-run may be used to create and start a transient .service or
.scope unit and run the specified COMMAND in it. It may also be used to
create and start a transient .path, .socket, or .timer unit, that
activates a .service unit when elapsing.

If a command is run as transient service unit, it will be started and
managed by the service manager like any other service, and thus shows
up in the output of systemctl list-units like any other unit. It will
run in a clean and detached execution environment, with the service
manager as its parent process. In this mode, systemd-run will start the
service asynchronously in the background and return after the command
has begun execution (unless --no-block or --wait are specified, see
below).

If a command is run as transient scope unit, it will be executed by
systemd-run itself as parent process and will thus inherit the
execution environment of the caller. However, the processes of the
command are managed by the service manager similar to normal services,
and will show up in the output of systemctl list-units. Execution in
this case is synchronous, and will return only when the command
finishes. This mode is enabled via the --scope switch (see below).

If a command is run with path, socket, or timer options such as
--on-calendar= (see below), a transient path, socket, or timer unit is
created alongside the service unit for the specified command. Only the
transient path, socket, or timer unit is started immediately, the
transient service unit will be triggered by the path, socket, or timer
unit. If the --unit= option is specified, the COMMAND may be omitted.
In this case, systemd-run creates only a .path, .socket, or .timer unit
that triggers the specified unit.

By default, services created with systemd-run default to the simple
type, see the description of Type= in systemd.service(5) for details.
Note that when this type is used the service manager (and thus the
systemd-run command) considers service start-up successful as soon as
the fork() for the main service process succeeded, i.e. before the
execve() is invoked, and thus even if the specified command cannot be
started. Consider using the exec service type (i.e.
--property=Type=exec) to ensure that systemd-run returns successfully
only if the specified command line has been successfully started.

OPTIONS
The following options are understood:

--no-ask-password
Do not query the user for authentication for privileged operations.

--scope
Create a transient .scope unit instead of the default transient
.service unit (see above).

--unit=, -u
Use this unit name instead of an automatically generated one.

--property=, -p
Sets a property on the scope or service unit that is created. This
option takes an assignment in the same format as systemctl(1)'s
set-property command.

--description=
Provide a description for the service, scope, path, socket, or
timer unit. If not specified, the command itself will be used as a
description. See Description= in systemd.unit(5).

--slice=
Make the new .service or .scope unit part of the specified slice,
instead of system.slice.

-r, --remain-after-exit
After the service process has terminated, keep the service around
until it is explicitly stopped. This is useful to collect runtime
information about the service after it finished running. Also see
RemainAfterExit= in systemd.service(5).

--send-sighup
When terminating the scope or service unit, send a SIGHUP
immediately after SIGTERM. This is useful to indicate to shells and
shell-like processes that the connection has been severed. Also see
SendSIGHUP= in systemd.kill(5).

--service-type=
Sets the service type. Also see Type= in systemd.service(5). This
option has no effect in conjunction with --scope. Defaults to
simple.

--uid=, --gid=
Runs the service process under the specified UNIX user and group.
Also see User= and Group= in systemd.exec(5).

--nice=
Runs the service process with the specified nice level. Also see
Nice= in systemd.exec(5).

--working-directory=
Runs the service process with the specified working directory. Also
see WorkingDirectory= in systemd.exec(5).

--same-dir, -d
Similar to --working-directory= but uses the current working
directory of the caller for the service to execute.

-E NAME=VALUE, --setenv=NAME=VALUE
Runs the service process with the specified environment variable
set. Also see Environment= in systemd.exec(5).

--pty, -t
When invoking the command, the transient service connects its
standard input, output and error to the terminal systemd-run is
invoked on, via a pseudo TTY device. This allows running programs
that expect interactive user input/output as services, such as
interactive command shells.

Note that machinectl(1)'s shell command is usually a better
alternative for requesting a new, interactive login session on the
local host or a local container.

See below for details on how this switch combines with --pipe.

--pipe, -P
If specified, standard input, output, and error of the transient
service are inherited from the systemd-run command itself. This
allows systemd-run to be used within shell pipelines. Note that
this mode is not suitable for interactive command shells and
similar, as the service process will not become a TTY controller
when invoked on a terminal. Use --pty instead in that case.

When both --pipe and --pty are used in combination the more
appropriate option is automatically determined and used.
Specifically, when invoked with standard input, output and error
connected to a TTY --pty is used, and otherwise --pipe.

When this option is used the original file descriptors systemd-run
receives are passed to the service processes as-is. If the service
runs with different privileges than systemd-run, this means the
service might not be able to re-open the passed file descriptors,
due to normal file descriptor access restrictions. If the invoked
process is a shell script that uses the echo "hello" > /dev/stderr
construct for writing messages to stderr, this might cause
problems, as this only works if stderr can be re-opened. To
mitigate this use the construct echo "hello" >&2 instead, which is
mostly equivalent and avoids this pitfall.

--shell, -S
A shortcut for "--pty --same-dir --wait --collect
--service-type=exec $SHELL", i.e. requests an interactive shell in
the current working directory, running in service context,
accessible with a single switch.

--quiet, -q
Suppresses additional informational output while running. This is
particularly useful in combination with --pty when it will suppress
the initial message explaining how to terminate the TTY connection.

--on-active=, --on-boot=, --on-startup=, --on-unit-active=,
--on-unit-inactive=
Defines a monotonic timer relative to different starting points for
starting the specified command. See OnActiveSec=, OnBootSec=,
OnStartupSec=, OnUnitActiveSec= and OnUnitInactiveSec= in
systemd.timer(5) for details. These options are shortcuts for
--timer-property= with the relevant properties. These options may
not be combined with --scope or --pty.

--on-calendar=
Defines a calendar timer for starting the specified command. See
OnCalendar= in systemd.timer(5). This option is a shortcut for
--timer-property=OnCalendar=. This option may not be combined with
--scope or --pty.

--on-clock-change, --on-timezone-change
Defines a trigger based on system clock jumps or timezone changes
for starting the specified command. See OnClockChange= and
OnTimezoneChange= in systemd.timer(5). These options are shortcuts
for --timer-property=OnClockChange=yes and
--timer-property=OnTimezoneChange=yes. These options may not be
combined with --scope or --pty.

--path-property=, --socket-property=, --timer-property=
Sets a property on the path, socket, or timer unit that is created.
This option is similar to --property= but applies to the transient
path, socket, or timer unit rather than the transient service unit
created. This option takes an assignment in the same format as
systemctl(1)'s set-property command. These options may not be
combined with --scope or --pty.

--no-block
Do not synchronously wait for the unit start operation to finish.
If this option is not specified, the start request for the
transient unit will be verified, enqueued and systemd-run will wait
until the unit's start-up is completed. By passing this argument,
it is only verified and enqueued. This option may not be combined
with --wait.

--wait
Synchronously wait for the transient service to terminate. If this
option is specified, the start request for the transient unit is
verified, enqueued, and waited for. Subsequently the invoked unit
is monitored, and it is waited until it is deactivated again (most
likely because the specified command completed). On exit, terse
information about the unit's runtime is shown, including total
runtime (as well as CPU usage, if --property=CPUAccounting=1 was
set) and the exit code and status of the main process. This output
may be suppressed with --quiet. This option may not be combined
with --no-block, --scope or the various path, socket, or timer
options.

-G, --collect
Unload the transient unit after it completed, even if it failed.
Normally, without this option, all units that ran and failed are
kept in memory until the user explicitly resets their failure state
with systemctl reset-failed or an equivalent command. On the other
hand, units that ran successfully are unloaded immediately. If this
option is turned on the "garbage collection" of units is more
aggressive, and unloads units regardless if they exited
successfully or failed. This option is a shortcut for
--property=CollectMode=inactive-or-failed, see the explanation for
CollectMode= in systemd.unit(5) for further information.

--user
Talk to the service manager of the calling user, rather than the
service manager of the system.

--system
Talk to the service manager of the system. This is the implied
default.

-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.

-h, --help
Print a short help text and exit.

--version
Print a short version string and exit.

All command line arguments after the first non-option argument become
part of the command line of the launched process. If a command is run
as service unit, the first argument needs to be an absolute program
path.

EXIT STATUS
On success, 0 is returned. If systemd-run failed to start the service,
a non-zero return value will be returned. If systemd-run waits for the
service to terminate, the return value will be propagated from the
service. 0 will be returned on success, including all the cases where
systemd considers a service to have exited cleanly, see the discussion
of SuccessExitStatus= in systemd.service(5).

EXAMPLES
Example 1. Logging environment variables provided by systemd to
services

# systemd-run env
Running as unit: run-19945.service
# journalctl -u run-19945.service
Sep 08 07:37:21 bupkis systemd[1]: Starting /usr/bin/env...
Sep 08 07:37:21 bupkis systemd[1]: Started /usr/bin/env.
Sep 08 07:37:21 bupkis env[19948]: PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin
Sep 08 07:37:21 bupkis env[19948]: LANG=en_US.UTF-8
Sep 08 07:37:21 bupkis env[19948]: BOOT_IMAGE=/vmlinuz-3.11.0-0.rc5.git6.2.fc20.x86_64

Example 2. Limiting resources available to a command

# systemd-run -p BlockIOWeight=10 updatedb

This command invokes the updatedb(8) tool, but lowers the block I/O
weight for it to 10. See systemd.resource-control(5) for more
information on the BlockIOWeight= property.

Example 3. Running commands at a specified time

The following command will touch a file after 30 seconds.

# date; systemd-run --on-active=30 --timer-property=AccuracySec=100ms /bin/touch /tmp/foo
Mon Dec 8 20:44:24 KST 2014
Running as unit: run-71.timer
Will run service as unit: run-71.service
# journalctl -b -u run-71.timer
-- Logs begin at Fri 2014-12-05 19:09:21 KST, end at Mon 2014-12-08 20:44:54 KST. --
Dec 08 20:44:38 container systemd[1]: Starting /bin/touch /tmp/foo.
Dec 08 20:44:38 container systemd[1]: Started /bin/touch /tmp/foo.
# journalctl -b -u run-71.service
-- Logs begin at Fri 2014-12-05 19:09:21 KST, end at Mon 2014-12-08 20:44:54 KST. --
Dec 08 20:44:48 container systemd[1]: Starting /bin/touch /tmp/foo...
Dec 08 20:44:48 container systemd[1]: Started /bin/touch /tmp/foo.

Example 4. Allowing access to the tty

The following command invokes /bin/bash as a service passing its
standard input, output and error to the calling TTY.

# systemd-run -t --send-sighup /bin/bash

Example 5. Start screen as a user service

$ systemd-run --scope --user screen
Running scope as unit run-r14b0047ab6df45bfb45e7786cc839e76.scope.

$ screen -ls
There is a screen on:
492..laptop (Detached)
1 Socket in /var/run/screen/S-fatima.

This starts the screen process as a child of the systemd --user process
that was started by user@.service, in a scope unit. A systemd.scope(5)
unit is used instead of a systemd.service(5) unit, because screen will
exit when detaching from the terminal, and a service unit would be
terminated. Running screen as a user unit has the advantage that it is
not part of the session scope. If KillUserProcesses=yes is configured
in logind.conf(5), the default, the session scope will be terminated
when the user logs out of that session.

The user@.service is started automatically when the user first logs in,
and stays around as long as at least one login session is open. After
the user logs out of the last session, user@.service and all services
underneath it are terminated. This behavior is the default, when
"lingering" is not enabled for that user. Enabling lingering means that
user@.service is started automatically during boot, even if the user is
not logged in, and that the service is not terminated when the user
logs out.

Enabling lingering allows the user to run processes without being
logged in, for example to allow screen to persist after the user logs
out, even if the session scope is terminated. In the default
configuration, users can enable lingering for themselves:

$ loginctl enable-linger

Example 6. Return value

$ systemd-run --user --wait true
$ systemd-run --user --wait -p SuccessExitStatus=11 bash -c 'exit 11'
$ systemd-run --user --wait -p SuccessExitStatus=SIGUSR1 bash -c 'kill -SIGUSR1 $$$$'

Those three invocations will succeed, i.e. terminate with an exit code
of 0.

SEE ALSO
systemd(1), systemctl(1), systemd.unit(5), systemd.service(5),
systemd.scope(5), systemd.slice(5), systemd.exec(5), systemd.resource-
control(5), systemd.timer(5), systemd-mount(1), machinectl(1)

systemd 245 SYSTEMD-RUN(1)

systemd-run

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