finit/doc/config

This section provides an overview of Finit's configuration system. For detailed information on specific topics, see the individual sections in the navigation menu.

Configuration File Syntax

A .conf file is a series of blocks. Every setting is a key inside one, so nothing has to be remembered by position:

service sysklogd {
    description = "System log daemon"
    runlevel    = "S123456789"
    envfile     = "-/etc/default/sysklogd"
    command     = "syslogd -F $SYSLOGD_ARGS"
}

Values are quoted strings, bare words, or integers. Lists use braces, and a block may carry a title, which becomes the service identity:

# shell comment
// C++ comment
/* C comment */

key      = "value"                 # string
number   = 20                      # integer
flag     = true                    # boolean
list     = { "one", "two" }        # string list
block title { key = "value" }      # titled section

path = "${HOME}/thing"             # environment expansion
include("/etc/finit.d/extra.conf") # include another file

Bare words work wherever a string is expected, so memory.max = 65M and restart = always need no quotes.

Two conventions

Keys are kebab-case, never snake_case or CamelCase: restart-sec, stop-timeout, reboot-watchdog.

Keys that take a list are plural: conditions, conflicts, capabilities, modules, extra-groups. Two imperatives keep their singular form because they are verbs rather than nouns: mknod and include.

Short forms

Nine keys have an alias. An alias may abbreviate the canonical name, or preserve the spelling the line-based format used; it never renames.

Canonical	Alias	Canonical	Alias
description	desc	manual-start	manual
conditions	cond	remain-after-exit	remain
capabilities	caps	stop-signal	halt
modules	mod	stop-timeout	kill
envfile	env

Optional paths

A leading - on a path means carry on if it is not there:

service foo {
    envfile = "-/etc/default/foo"   # skip the file if missing
    command = "-/usr/sbin/foo"      # skip the whole block if missing
}

That is the only mark meaning "optional". Two others mean something else: ! on runlevel inverts the set, e.g. runlevel = "!12345", and ~ on a condition propagates a reload from the service it names. Both are covered where they apply.

Both Formats Are Read

Finit also reads the line-based format it has always used, where a stanza is a keyword followed by values whose meaning comes from their position:

service [S123456789] env:-/etc/default/sysklogd syslogd -F $SYSLOGD_ARGS -- System log daemon

That format still works and is not going away. It is frozen at the Finit 4.x feature set, so new settings appear only in the block format, and the documentation is written in blocks throughout. To convert a file, see the Syntax Migration Guide.

There is no new file extension and no marker line. Every file is still *.conf, and Finit decides which format a file is in by reading it: if it parses as blocks it is a block file, otherwise it goes to the line-based parser. A file is one format or the other, never a mix.

Because the two are told apart before either parser commits, a typo reports its own file and line instead of being mistaken for the other format:

parse error: /etc/finit.d/foo.conf:3: no such option 'commnad'

The .conf files /etc/finit.conf and /etc/finit.d/* support many settings. Some are restricted, e.g., only available at bootstrap, runlevel S. Read on in Files & Layout for more on how to structure your .conf files.

For details on restrictions, see Limitations.