Reference sections kept pointing at the line-based format they no longer
document. `sysv` and `task` sent the reader to Services for "<COND>",
the cgroups chapter opened by listing three legacy directives and then
explained further down that only two of them exist here, and the logging
chapter still gave "log:prio:facility.level,tag:ident" as the full
syntax.
Some claims were wrong independent of the format:
- a sysv is a supervised daemon, grouped with service in
SVC_TYPE_DAEMON, not a variation on task
- restart-max has no upper bound of 255, or any other
- the built-in rescue fallback runs in 12345789, not 12345
- conditional loading quotes system/10-hotplug.conf, not
system/hotplug.conf
- the key spells conflicts, not conflict
- the built-in getty no longer wants TERM last, it is a key
`if` takes either a service name or, in angle brackets, a condition,
decided in svc_ifthen(). Only the examples showed this, so it is now
said.
Terminology follows the split index.md already draws: a block is the new
format, a stanza the line-based one.
src/rescue.conf was still line-based, missed because it sits in src/
rather than system/ or contrib/.
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
3.2 KiB
run (sequence)
Syntax: run NAME { command = "/path/to/cmd ARGS" }
Conditions, runlevels, and the other settings a
runblock takes are described in Service Options.
One-shot command to run in sequence when entering a runlevel, with
optional arguments and description. run commands are guaranteed to be
completed before running the next command. Useful when serialization is
required.
Warning
Try to avoid the
runcommand. It blocks much of the functionality in Finit, like (re)starting other (perhaps crashing) services while aruntask is executing. Use other synchronization mechanisms instead, like conditions.
Incomplete list of unsupported initctl commands in run tasks:
initctl runlevel N, setting runlevelinitctl rebootinitctl haltinitctl poweroffinitctl suspend
To prevent initctl from calling Finit when enabling and disabling
services from inside a run task, use the --force option. See
also the --quiet and --batch options.
task (parallel)
Syntax: task NAME { command = "/path/to/cmd ARGS" }
A
taskblock takes the same settings asrun, see Service Options.
One-shot like 'run', but starts in parallel with the next command.
Both run and task commands are run in a shell, so basic pipes and
redirects can be used:
task bar {
runlevel = "S"
command = "echo \"foo\" | cat >/tmp/bar"
}
Please note, ;, &&, ||, and similar are not supported. Any
non-trivial constructs are better placed in a separate shell script.
remain-after-exit
By default, a run or task will re-run each time its runlevel is
entered, and its exec-stop-post script does not run on completion.
With remain-after-exit, the task runs once and does not re-run on
runlevel re-entry:
task firewall {
description = "Firewall setup"
runlevel = "2345"
remain-after-exit = true
command = "/usr/sbin/setup-firewall"
}
This has the following effects:
- The task does not re-run on runlevel re-entry
- The
exec-stop-postscript runs when:- The task is explicitly stopped (
initctl stop NAME) - The task leaves its valid runlevels (e.g., runlevel change)
- The task is explicitly stopped (
This is useful for tasks that set up persistent state where:
- Cleanup should only happen on explicit stop or when leaving valid runlevels
- The setup should not be re-run on every runlevel entry
Example: Setting up firewall rules with cleanup on shutdown:
task firewall {
description = "Firewall setup"
runlevel = "2345"
remain-after-exit = true
exec-stop-post = "/usr/sbin/teardown-firewall"
command = "/usr/sbin/setup-firewall"
}
The firewall rules are created once. The exec-stop-post script runs when
entering runlevel 0 (halt) or 6 (reboot), or on explicit stop.
Note
The
remain-after-exitsetting is not supported for bootstrap-only tasks (tasks with only runlevel S). Bootstrap tasks are deleted immediately after completion, and theirexec-stop-postscripts never run. A warning is logged ifremain-after-exitis used on such tasks.