<literal>%i</literal> specifier in many of the
configuration options. Other specifiers that may be
used are <literal>%n</literal>, <literal>%N</literal>,
- <literal>%p</literal>, <literal>%P</literal> and
- <literal>%I</literal>, for the full unit name, the
- unescaped unit name, the prefix name, the unescaped
- prefix name and the unescaped instance name,
- respectively. The prefix name here refers to the
- string before the @, i.e. "getty" in the example
- above, where "tty3" is the instance name.</para>
+ <literal>%p</literal>, <literal>%P</literal>,
+ <literal>%I</literal> and <literal>%f</literal>, for
+ the full unit name, the unescaped unit name, the
+ prefix name, the unescaped prefix name, the unescaped
+ instance name and the unescaped filename,
+ respectively. The unescaped filename is either the
+ unescaped instance name (if set) with / prepended (if
+ necessary), or the prefix name similarly prepended
+ with /. The prefix name here refers to the string
+ before the @, i.e. "getty" in the example above, where
+ "tty3" is the instance name.</para>
+
+ <para>If a unit file is empty (i.e. has the file size
+ 0) or is symlinked to <filename>/dev/null</filename>
+ its configuration will not be loaded and it appears
+ with a load state of <literal>masked</literal>, and
+ cannot be activated. Use this as an effective way to
+ fully disable a unit, making it impossible to start it
+ even manually.</para>
+
+ <para>The unit file format is covered by the
+ <ulink
+ url="http://www.freedesktop.org/wiki/Software/systemd/InterfaceStabilityPromise">Interface
+ Stability Promise</ulink>.</para>
</refsect1>
<refsect1>
services.</para></listitem>
</varlistentry>
-
<varlistentry>
<term><varname>RequiresOverridable=</varname></term>
details see above.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>BindTo=</varname></term>
+
+ <listitem><para>Configures requirement
+ dependencies, very similar in style to
+ <varname>Requires=</varname>, however
+ in addition to this behaviour it also
+ declares that this unit is stopped
+ when any of the units listed suddenly
+ disappears. Units can suddenly,
+ unexpectedly disappear if a service
+ terminates on its own choice, a device
+ is unplugged or a mount point
+ unmounted without involvement of
+ systemd.</para></listitem>
+ </varlistentry>
+
<varlistentry>
<term><varname>Conflicts=</varname></term>
<listitem><para>Lists one or more
units that are activated when this
- unit fails (i.e. enters maintenance
- state).</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><varname>RecursiveStop=</varname></term>
-
- <listitem><para>Takes a boolean
- argument. If <option>true</option> and
- the unit stops without being requested
- by the user, all units
- depending on it will be stopped as
- well. (e.g. if a service exits or
- crashes on its own behalf, units using
- it will be stopped) Note that normally
- if a unit stops without a user request,
- units depending on it will not be
- terminated. Only if the user requested
- shutdown of a unit, all units depending
- on that unit will be shut down as well
- and at the same time. Defaults to
- <option>false</option>.</para></listitem>
+ unit enters the
+ '<literal>failed</literal>'
+ state.</para></listitem>
</varlistentry>
<varlistentry>
ones.</para></listitem>
</varlistentry>
- <varlistentry>
- <term><varname>IgnoreDependencyFailure=</varname></term>
-
- <listitem><para>Takes a boolean
- argument. If <option>true</option> and
- a requirement dependency of this unit
- fails to start up this unit will be
- started nonetheless, ignoring that
- failure. If <option>false</option>
- (the default) and a dependency unit
- fails the unit will immediately fail
- too and the job is removed.</para></listitem>
- </varlistentry>
-
<varlistentry>
<term><varname>JobTimeoutSec=</varname></term>
time. If this time limit is reached
the job will be cancelled, the unit
however will not change state or even
- enter maintenance mode. This value
- defaults to 0 (job timeouts disabled),
- except for device units. NB: this
- timeout is independent from any
- unit-specific timeout (for example,
- the timeout set with
+ enter the '<literal>failed</literal>'
+ mode. This value defaults to 0 (job
+ timeouts disabled), except for device
+ units. NB: this timeout is independent
+ from any unit-specific timeout (for
+ example, the timeout set with
<varname>Timeout=</varname> in service
- units) as the job timeout has no effect
- on the unit itself, only on the job
- that might be pending for it. Or in
- other words: unit-specific timeouts
+ units) as the job timeout has no
+ effect on the unit itself, only on the
+ job that might be pending for it. Or
+ in other words: unit-specific timeouts
are useful to abort unit state
changes, and revert them. The job
timeout set with this option however
- is useful to abort only the job waiting
- for the unit state to change.</para></listitem>
+ is useful to abort only the job
+ waiting for the unit state to
+ change.</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>ConditionPathExists=</varname></term>
+ <term><varname>ConditionDirectoryNotEmpty=</varname></term>
+ <term><varname>ConditionKernelCommandLine=</varname></term>
+ <term><varname>ConditionNull=</varname></term>
+
+ <listitem><para>Before starting a unit
+ verify that the specified condition is
+ true. With
+ <varname>ConditionPathExists=</varname>
+ a file existance condition can be
+ checked before a unit is started. If
+ the specified absolute path name does
+ not exist startup of a unit will not
+ actually happen, however the unit is
+ still useful for ordering purposes in
+ this case. The condition is checked at
+ the time the queued start job is to be
+ executed. If the absolute path name
+ passed to
+ <varname>ConditionPathExists=</varname>
+ is prefixed with an exclamation mark
+ (!), the test is negated, and the unit
+ only started if the path does not
+ exist. <varname>ConditionDirectoryNotEmpty=</varname>
+ is similar to
+ <varname>ConditionPathExists=</varname>
+ but verifies whether a certain path is
+ exists and is a non-empty
+ directory. Similarly
+ <varname>ConditionKernelCommandLine=</varname>
+ may be used to check whether a
+ specific kernel command line option is
+ set (or if prefixed with the
+ exclamation mark unset). The argument
+ must either be a single word, or an
+ assignment (i.e. two words, separated
+ by the equality sign). In the former
+ case the kernel command line is
+ searched for the word appearing as is,
+ or as left hand side of an
+ assignment. In the latter case the
+ exact assignment is looked for with
+ right and left hand side
+ matching. Finally,
+ <varname>ConditionNull=</varname> may
+ be used to add a constant condition
+ check value to the unit. It takes a
+ boolean argument. If set to
+ <varname>false</varname> the condition
+ will always fail, otherwise
+ succeed. If multiple conditions are
+ specified the unit will be executed
+ if at least one of them applies
+ (i.e. a logical OR is
+ applied).</para></listitem>
+ </varlistentry>
</variablelist>
<para>Unit file may include a [Install] section, which
~ianmdlvl / elogind.git / blobdiff