start-up type for this service
unit. One of <option>simple</option>,
<option>forking</option>,
- <option>finish</option>,
+ <option>oneshot</option>,
<option>dbus</option>,
<option>notify</option>.</para>
configured with
<varname>ExecStart=</varname> is the
main process of the service. In this
- mode, communication channels must be
- installed before the daemon is started
- up (e.g. sockets set up by systemd,
- via socket activation), as systemd
- will immediately proceed starting
- follow-up units.</para>
+ mode, if the process offers
+ functionality to other processes on
+ the system its communication channels
+ should be installed before the daemon
+ is started up (e.g. sockets set up by
+ systemd, via socket activation), as
+ systemd will immediately proceed
+ starting follow-up units.</para>
<para>If set to
<option>forking</option> it is
expected that the process configured
with <varname>ExecStart=</varname>
- will start up and call
- <function>fork()</function>. The
- parent process is expected to finish
- when start-up is complete and all
- communication channels set up. The
- child continues to run as the main
- daemon process. This is the behaviour
- of traditional UNIX daemons. If this
+ will call <function>fork()</function>
+ as part of its start-up. The parent process is
+ expected to exit when start-up is
+ complete and all communication
+ channels set up. The child continues
+ to run as the main daemon
+ process. This is the behaviour of
+ traditional UNIX daemons. If this
setting is used, it is recommended to
also use the
<varname>PIDFile=</varname> option, so
exits.</para>
<para>Behaviour of
- <option>finish</option> is similar
+ <option>oneshot</option> is similar
to <option>simple</option>, however
it is expected that the process has to
exit before systemd starts follow-up
- units. <varname>ValidNoProcess=</varname>
+ units. <varname>RemainAfterExit=</varname>
is particularly useful for this type
of service.</para>
will proceed starting follow-up units
after the D-Bus bus name has been
acquired. Service units with this
- option configured implicitly have
+ option configured implicitly gain
dependencies on the
<filename>dbus.target</filename>
unit.</para>
notification message has been sent. If
this option is used
<varname>NotifyAccess=</varname> (see
- below) must be set to open access to
+ below) should be set to open access to
the notification socket provided by
systemd. If
<varname>NotifyAccess=</varname> is not
- set, it will be implicitly set to
+ set, it will implicitly be set to
<option>main</option>.</para>
</listitem>
</varlistentry>
<varlistentry>
- <term><varname>ValidNoProcess=</varname></term>
+ <term><varname>RemainAfterExit=</varname></term>
<listitem><para>Takes a boolean value
that specifies whether the service
arguments for the process. It is
mandatory to set this option for all
services. This option may not be
- specified more than once. Optionally,
- if the absolute file name is prefixed
- with <literal>@</literal>, the second
- token will be passed as
+ specified more than once, except when
+ <varname>Type=oneshot</varname> is
+ used in which case more than one
+ <varname>ExecStart=</varname> line is
+ accepted which are then invoked one by
+ one, sequentially in the order they
+ appear in the unit file.</para>
+
+ <para>Optionally, if the absolute file
+ name is prefixed with
+ <literal>@</literal>, the second token
+ will be passed as
<literal>argv[0]</literal> to the
executed process, followed by the
- further arguments specified. Unless
- <varname>Type=forking</varname> is set,
- the process started via this command
- line will be considered the main
- process of the
- daemon.</para></listitem>
+ further arguments specified. If the
+ first token is prefixed with
+ <literal>-</literal> an exit code of
+ the command normally considered a
+ failure (i.e. non-zero exit status or
+ abormal exit due to signal) is ignored
+ and considered success. If both
+ <literal>-</literal> and
+ <literal>@</literal> are used for the
+ same command the former must preceed
+ the latter. Unless
+ <varname>Type=forking</varname> is
+ set, the process started via this
+ command line will be considered the
+ main process of the daemon. The
+ command line accepts % specifiers as
+ described in
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>. On
+ top of that basic environment variable
+ substitution is supported, where
+ <literal>${FOO}</literal> is replaced
+ by the string value of the environment
+ variable of the same name. Also
+ <literal>$FOO</literal> may appear as
+ separate word on the command line in
+ which case the variable is replaced by
+ its value split at whitespaces. Note
+ that the first argument (i.e. the
+ binary to execute) may not be a
+ variable, and must be a literal and
+ absolute path name.</para></listitem>
</varlistentry>
<varlistentry>
<listitem><para>Additional commands
that are executed before (resp. after)
the command in
- <varname>ExecStart=</varname>. If
- specified more than once, all commands
- are executed one after the other,
- serially. Use of these settings is
- optional.</para></listitem>
+ <varname>ExecStart=</varname>. Multiple
+ command lines may be concatenated in a
+ single directive, by separating them
+ by semicolons (these semicolons must
+ be passed as separate words). In that
+ case, the commands are executed one
+ after the other,
+ serially. Alternatively, these
+ directives may be specified more than
+ once whith the same effect. However,
+ the latter syntax is not recommended
+ for compatibility with parsers
+ suitable for XDG
+ <filename>.desktop</filename> files.
+ Use of these settings is
+ optional. Specifier and environment
+ variable substitution is
+ supported.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>ExecReload=</varname></term>
<listitem><para>Commands to execute to
trigger a configuration reload in the
- service. If used more than once, all
- commands are executed one after the
- other, serially. Use of this setting is optional.
- </para></listitem>
+ service. This argument takes multiple
+ command lines, following the same
+ scheme as pointed out for
+ <varname>ExecStartPre=</varname>
+ above. Use of this setting is
+ optional. Specifier and environment
+ variable substitution is supported
+ here following the same scheme as for
+ <varname>ExecStart=</varname>. One
+ special environment variable is set:
+ if known <literal>$MAINPID</literal> is
+ set to the main process of the
+ daemon, and may be used for command
+ lines like the following:
+ <command>/bin/kill -HUP
+ $MAINPID</command>.</para></listitem>
</varlistentry>
<varlistentry>
<term><varname>ExecStop=</varname></term>
<listitem><para>Commands to execute to
stop the service started via
- <varname>ExecStart=</varname>. If used
- more than once, all commands are
- executed one after the other,
- serially. Use of this setting is
+ <varname>ExecStart=</varname>. This
+ argument takes multiple command lines,
+ following the same scheme as pointed
+ out for
+ <varname>ExecStartPre=</varname>
+ above. Use of this setting is
optional. All processes remaining for
a service after the commands
configured in this option are run are
(see below). If this option is not
specified the process is terminated
right-away when service stop is
- requested.</para></listitem>
+ requested. Specifier and environment
+ variable substitution is supported
+ (including
+ <literal>$MAINPID</literal>, see
+ above).</para></listitem>
</varlistentry>
<varlistentry>
that are executed after the service
was stopped using the commands
configured in
- <varname>ExecStop=</varname>. If
- specified more than once, all commands
- are executed one after the other,
- serially. Use of these settings is
- optional.</para></listitem>
+ <varname>ExecStop=</varname>. This
+ argument takes multiple command lines,
+ following the same scheme as pointed
+ out for
+ <varname>ExecStartPre</varname>. Use
+ of these settings is
+ optional. Specifier and environment
+ variable substitution is
+ supported.</para></listitem>
</varlistentry>
<varlistentry>
<varlistentry>
<term><varname>Restart=</varname></term>
<listitem><para>Configures whether the
- main service process shall be restarted when
- it exists. Takes one of
- <option>once</option>,
- <option>restart-on-success</option> or
- <option>restart-always</option>. If
- set to <option>once</option> (the
- default) the service will not be
- restarted when it exits. If set to
- <option>restart-on-success</option> it
- will be restarted only when it exited
- cleanly, i.e. terminated with an exit
- code of 0. If set to
- <option>restart-always</option> the
+ main service process shall be
+ restarted when it exists. Takes one of
+ <option>no</option>,
+ <option>on-success</option>,
+ <option>on-failure</option>,
+ <option>on-abort</option> or
+ <option>always</option>. If set to
+ <option>no</option> (the default) the
+ service will not be restarted when it
+ exits. If set to
+ <option>on-success</option> it will be
+ restarted only when it exited cleanly,
+ i.e. terminated with an exit code of
+ 0. If set to
+ <option>on-failure</option> it will be
+ restared only when it exited with an
+ exit code not equalling 0, or when
+ terminated by a signal. If set to
+ <option>on-abort</option> it will be
+ restarted only if it exits due to
+ reception of an uncaught signal. If
+ set to <option>always</option> the
service will be restarted regardless
whether it exited cleanly or not, or
got terminated abnormally by a
<varname>Type=notify</varname> (see above).</para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><varname>Sockets=</varname></term>
+ <listitem><para>Specifies the name of
+ the socket units this service shall
+ inherit the sockets from when the
+ service (ignoring the different suffix
+ of course) is started. Normally it
+ should not be necessary to use this
+ setting as all sockets whose unit
+ shares the same name as the service
+ are passed to the spawned
+ process.</para>
+
+ <para>Note that the same socket may be
+ passed to multiple processes at the
+ same time. Also note that a different
+ service may be activated on incoming
+ traffic than inherits the sockets. Or
+ in other words: The
+ <varname>Service=</varname> setting of
+ <filename>.socket</filename> units
+ doesn't have to match the inverse of the
+ <varname>Sockets=</varname> setting of
+ the <filename>.service</filename> it
+ refers to.</para></listitem>
+ </varlistentry>
+
</variablelist>
</refsect1>
~ianmdlvl / elogind.git / blobdiff