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diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml deleted file mode 100644 index 7c3a6c75f8..0000000000 --- a/man/systemd.unit.xml +++ /dev/null @@ -1,1143 +0,0 @@ -<?xml version='1.0'?> <!--*-nxml-*--> -<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" - "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> - -<!-- - This file is part of systemd. - - Copyright 2010 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="systemd.unit"> - - <refentryinfo> - <title>systemd.unit</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>systemd.unit</refentrytitle> - <manvolnum>5</manvolnum> - </refmeta> - - <refnamediv> - <refname>systemd.unit</refname> - <refpurpose>Unit configuration</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <para><filename>systemd.service</filename>, - <filename>systemd.socket</filename>, - <filename>systemd.device</filename>, - <filename>systemd.mount</filename>, - <filename>systemd.automount</filename>, - <filename>systemd.swap</filename>, - <filename>systemd.target</filename>, - <filename>systemd.path</filename>, - <filename>systemd.timer</filename>, - <filename>systemd.snapshot</filename></para> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para>A unit configuration file encodes information - about a service, a socket, a device, a mount point, an - automount point, a swap file or partition, a start-up - target, a file system path or a timer controlled and - supervised by - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>. The - syntax is inspired by <ulink - url="http://standards.freedesktop.org/desktop-entry-spec/latest/">XDG - Desktop Entry Specification</ulink> <filename>.desktop</filename> files, which are in turn - inspired by Microsoft Windows - <filename>.ini</filename> files.</para> - - <para>This man page lists the common configuration - options of all the unit types. These options need to - be configured in the [Unit] or [Install] - sections of the unit files.</para> - - <para>In addition to the generic [Unit] and [Install] - sections described here, each unit may have a - type-specific section, e.g. [Service] for a service - unit. See the respective man pages for more - information.</para> - - <para>Unit files may contain additional options on top - of those listed here. If systemd encounters an unknown - option it will write a warning log message but - continue loading the unit. If an option is prefixed - with <option>X-</option> it is ignored completely by - systemd. Applications may use this to include - additional information in the unit files.</para> - - <para>Boolean arguments used in unit files can be - written in various formats. For positive settings the - strings <option>1</option>, <option>yes</option>, - <option>true</option> and <option>on</option> are - equivalent. For negative settings the strings - <option>0</option>, <option>no</option>, - <option>false</option> and <option>off</option> are - equivalent.</para> - - <para>Time span values encoded in unit files can be - written in various formats. A stand-alone number - specifies a time in seconds. If suffixed with a time - unit, the unit is honored. A concatenation of multiple - values with units is supported, in which case the - values are added up. Example: "50" refers to 50 - seconds; "2min 200ms" refers to 2 minutes plus 200 - milliseconds, i.e. 120200ms. The following time units - are understood: s, min, h, d, w, ms, us. For details - see - <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para> - - <para>Empty lines and lines starting with # or ; are - ignored. This may be used for commenting. Lines ending - in a backslash are concatenated with the following - line while reading and the backslash is replaced by a - space character. This may be used to wrap long lines.</para> - - <para>Along with a unit file - <filename>foo.service</filename> the directory - <filename>foo.service.wants/</filename> may exist. All - unit files symlinked from such a directory are - implicitly added as dependencies of type - <varname>Wanted=</varname> to the unit. This is useful - to hook units into the start-up of other units, - without having to modify their unit files. For details - about the semantics of <varname>Wanted=</varname> see - below. The preferred way to create symlinks in the - <filename>.wants/</filename> directory of a unit file - is with the <command>enable</command> command of the - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> - tool which reads information from the [Install] - section of unit files (see below). A similar - functionality exists for <varname>Requires=</varname> - type dependencies as well, the directory suffix is - <filename>.requires/</filename> in this case.</para> - - <para>Along with a unit file - <filename>foo.service</filename> a directory - <filename>foo.service.d/</filename> may exist. All - files with the suffix <filename>.conf</filename> from - this directory will be parsed after the file itself is - parsed. This is useful to alter or add configuration - settings to a unit, without having to modify their - unit files. Make sure that the file that is included - has the appropriate section headers before any - directive.</para> - - <para>If a line starts with <option>.include</option> - followed by a file name, the specified file will be - parsed at this point. Make sure that the file that is - included has the appropriate section headers before - any directives.</para> - - <para>Note that while systemd offers a flexible - dependency system between units it is recommended to - use this functionality only sparingly and instead rely - on techniques such as bus-based or socket-based - activation which make dependencies implicit, resulting - in a both simpler and more flexible system.</para> - - <para>Some unit names reflect paths existing in the - file system name space. Example: a device unit - <filename>dev-sda.device</filename> refers to a device - with the device node <filename>/dev/sda</filename> in - the file system namespace. If this applies a special - way to escape the path name is used, so that the - result is usable as part of a file name. Basically, - given a path, "/" is replaced by "-", and all - unprintable characters and the "-" are replaced by - C-style "\x20" escapes. The root directory "/" is - encoded as single dash, while otherwise the initial - and ending "/" is removed from all paths during - transformation. This escaping is reversible.</para> - - <para>Optionally, units may be instantiated from a - template file at runtime. This allows creation of - multiple units from a single configuration file. If - systemd looks for a unit configuration file it will - first search for the literal unit name in the - filesystem. If that yields no success and the unit - name contains an @ character, systemd will look for a - unit template that shares the same name but with the - instance string (i.e. the part between the @ character - and the suffix) removed. Example: if a service - <filename>getty@tty3.service</filename> is requested - and no file by that name is found, systemd will look - for <filename>getty@.service</filename> and - instantiate a service from that configuration file if - it is found.</para> - - <para>To refer to the instance string from - within the configuration file you may use the special - <literal>%i</literal> specifier in many of the - configuration options. See below for details.</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> - <title>Options</title> - - <para>Unit file may include a [Unit] section, which - carries generic information about the unit that is not - dependent on the type of unit:</para> - - <variablelist class='unit-directives'> - - <varlistentry> - <term><varname>Description=</varname></term> - <listitem><para>A free-form string - describing the unit. This is intended - for use in UIs to show descriptive - information along with the unit - name.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Documentation=</varname></term> - <listitem><para>A space separated list - of URIs referencing documentation for - this unit or its - configuration. Accepted are only URIs - of the types - <literal>http://</literal>, - <literal>https://</literal>, - <literal>file:</literal>, - <literal>info:</literal>, - <literal>man:</literal>. For more - information about the syntax of these - URIs see - <citerefentry><refentrytitle>uri</refentrytitle><manvolnum>7</manvolnum></citerefentry>. The - URIs should be listed in order of - relevance, starting with the most - relevant. It is a good idea to first - reference documentation that explains - what the unit's purpose is, followed - by how it is configured, followed by - any other related documentation. This - option may be specified more than once - in which case the specified list of - URIs is merged. If the empty string is - assigned to this option the list is - reset and all prior assignments will - have no effect.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Requires=</varname></term> - - <listitem><para>Configures requirement - dependencies on other units. If this - unit gets activated, the units listed - here will be activated as well. If one - of the other units gets deactivated or - its activation fails, this unit will - be deactivated. This option may be - specified more than once, in which - case requirement dependencies for all - listed names are created. Note that - requirement dependencies do not - influence the order in which services - are started or stopped. This has to be - configured independently with the - <varname>After=</varname> or - <varname>Before=</varname> options. If - a unit - <filename>foo.service</filename> - requires a unit - <filename>bar.service</filename> as - configured with - <varname>Requires=</varname> and no - ordering is configured with - <varname>After=</varname> or - <varname>Before=</varname>, then both - units will be started simultaneously - and without any delay between them if - <filename>foo.service</filename> is - activated. Often it is a better choice - to use <varname>Wants=</varname> - instead of - <varname>Requires=</varname> in order - to achieve a system that is more - robust when dealing with failing - services.</para> - - <para>Note that dependencies of this - type may also be configured outside of - the unit configuration file by - adding a symlink to a - <filename>.requires/</filename> directory - accompanying the unit file. For - details see above.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>RequiresOverridable=</varname></term> - - <listitem><para>Similar to - <varname>Requires=</varname>. - Dependencies listed in - <varname>RequiresOverridable=</varname> - which cannot be fulfilled or fail to - start are ignored if the startup was - explicitly requested by the user. If - the start-up was pulled in indirectly - by some dependency or automatic - start-up of units that is not - requested by the user this dependency - must be fulfilled and otherwise the - transaction fails. Hence, this option - may be used to configure dependencies - that are normally honored unless the - user explicitly starts up the unit, in - which case whether they failed or not - is irrelevant.</para></listitem> - - </varlistentry> - <varlistentry> - <term><varname>Requisite=</varname></term> - <term><varname>RequisiteOverridable=</varname></term> - - <listitem><para>Similar to - <varname>Requires=</varname> - and <varname>RequiresOverridable=</varname>, respectively. However, - if a unit listed here is not started - already it will not be started and the - transaction fails - immediately.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Wants=</varname></term> - - <listitem><para>A weaker version of - <varname>Requires=</varname>. A unit - listed in this option will be started - if the configuring unit is. However, - if the listed unit fails to start up - or cannot be added to the transaction - this has no impact on the validity of - the transaction as a whole. This is - the recommended way to hook start-up - of one unit to the start-up of another - unit.</para> - - <para>Note that dependencies of this - type may also be configured outside of - the unit configuration file by - adding a symlink to a - <filename>.wants/</filename> directory - accompanying the unit file. For - details see above.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>BindsTo=</varname></term> - - <listitem><para>Configures requirement - dependencies, very similar in style to - <varname>Requires=</varname>, however - in addition to this behavior 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>PartOf=</varname></term> - - <listitem><para>Configures dependencies - similar to <varname>Requires=</varname>, - but limited to stopping and restarting - of units. When systemd stops or restarts - the units listed here, the action is - propagated to this unit. - Note that this is a one way dependency - - changes to this unit do not affect the - listed units. - </para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Conflicts=</varname></term> - - <listitem><para>Configures negative - requirement dependencies. If a unit - has a - <varname>Conflicts=</varname> setting - on another unit, starting the former - will stop the latter and vice - versa. Note that this setting is - independent of and orthogonal to the - <varname>After=</varname> and - <varname>Before=</varname> ordering - dependencies.</para> - - <para>If a unit A that conflicts with - a unit B is scheduled to be started at - the same time as B, the transaction - will either fail (in case both are - required part of the transaction) or - be modified to be fixed (in case one - or both jobs are not a required part - of the transaction). In the latter - case the job that is not the required - will be removed, or in case both are - not required the unit that conflicts - will be started and the unit that is - conflicted is - stopped.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Before=</varname></term> - <term><varname>After=</varname></term> - - <listitem><para>Configures ordering - dependencies between units. If a unit - <filename>foo.service</filename> - contains a setting - <option>Before=bar.service</option> - and both units are being started, - <filename>bar.service</filename>'s - start-up is delayed until - <filename>foo.service</filename> is - started up. Note that this setting is - independent of and orthogonal to the - requirement dependencies as configured - by <varname>Requires=</varname>. It is - a common pattern to include a unit - name in both the - <varname>After=</varname> and - <varname>Requires=</varname> option in - which case the unit listed will be - started before the unit that is - configured with these options. This - option may be specified more than - once, in which case ordering - dependencies for all listed names are - created. <varname>After=</varname> is - the inverse of - <varname>Before=</varname>, i.e. while - <varname>After=</varname> ensures that - the configured unit is started after - the listed unit finished starting up, - <varname>Before=</varname> ensures the - opposite, i.e. that the configured - unit is fully started up before the - listed unit is started. Note that when - two units with an ordering dependency - between them are shut down, the - inverse of the start-up order is - applied. i.e. if a unit is configured - with <varname>After=</varname> on - another unit, the former is stopped - before the latter if both are shut - down. If one unit with an ordering - dependency on another unit is shut - down while the latter is started up, - the shut down is ordered before the - start-up regardless whether the - ordering dependency is actually of - type <varname>After=</varname> or - <varname>Before=</varname>. If two - units have no ordering dependencies - between them they are shut down - or started up simultaneously, and - no ordering takes - place. </para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>OnFailure=</varname></term> - - <listitem><para>Lists one or more - units that are activated when this - unit enters the - '<literal>failed</literal>' - state.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>PropagatesReloadTo=</varname></term> - <term><varname>ReloadPropagatedFrom=</varname></term> - - <listitem><para>Lists one or more - units where reload requests on the - unit will be propagated to/on the - other unit will be propagated - from. Issuing a reload request on a - unit will automatically also enqueue a - reload request on all units that the - reload request shall be propagated to - via these two - settings.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>RequiresMountsFor=</varname></term> - - <listitem><para>Takes a space - separated list of absolute paths. Automatically - adds dependencies of type - <varname>Requires=</varname> and - <varname>After=</varname> for all - mount units required to access the - specified path.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>OnFailureIsolate=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> the - unit listed in - <varname>OnFailure=</varname> will be - enqueued in isolation mode, i.e. all - units that are not its dependency will - be stopped. If this is set only a - single unit may be listed in - <varname>OnFailure=</varname>. Defaults - to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>IgnoreOnIsolate=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - this unit will not be stopped when - isolating another unit. Defaults to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>IgnoreOnSnapshot=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - this unit will not be included in - snapshots. Defaults to - <option>true</option> for device and - snapshot units, <option>false</option> - for the others.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>StopWhenUnneeded=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - this unit will be stopped when it is - no longer used. Note that in order to - minimize the work to be executed, - systemd will not stop units by default - unless they are conflicting with other - units, or the user explicitly - requested their shut down. If this - option is set, a unit will be - automatically cleaned up if no other - active unit requires it. Defaults to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>RefuseManualStart=</varname></term> - <term><varname>RefuseManualStop=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - this unit can only be activated - or deactivated indirectly. In - this case explicit start-up - or termination requested by the - user is denied, however if it is - started or stopped as a - dependency of another unit, start-up - or termination will succeed. This - is mostly a safety feature to ensure - that the user does not accidentally - activate units that are not intended - to be activated explicitly, and not - accidentally deactivate units that are - not intended to be deactivated. - These options default to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>AllowIsolate=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - this unit may be used with the - <command>systemctl isolate</command> - command. Otherwise this will be - refused. It probably is a good idea to - leave this disabled except for target - units that shall be used similar to - runlevels in SysV init systems, just - as a precaution to avoid unusable - system states. This option defaults to - <option>false</option>.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>DefaultDependencies=</varname></term> - - <listitem><para>Takes a boolean - argument. If <option>true</option> - (the default), a few default - dependencies will implicitly be - created for the unit. The actual - dependencies created depend on the - unit type. For example, for service - units, these dependencies ensure that - the service is started only after - basic system initialization is - completed and is properly terminated on - system shutdown. See the respective - man pages for details. Generally, only - services involved with early boot or - late shutdown should set this option - to <option>false</option>. It is - highly recommended to leave this - option enabled for the majority of - common units. If set to - <option>false</option> this option - does not disable all implicit - dependencies, just non-essential - ones.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>JobTimeoutSec=</varname></term> - - <listitem><para>When clients are - waiting for a job of this unit to - complete, time out after the specified - time. If this time limit is reached - the job will be cancelled, the unit - however will not change state or even - 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 - 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> - </varlistentry> - - <varlistentry> - <term><varname>ConditionPathExists=</varname></term> - <term><varname>ConditionPathExistsGlob=</varname></term> - <term><varname>ConditionPathIsDirectory=</varname></term> - <term><varname>ConditionPathIsSymbolicLink=</varname></term> - <term><varname>ConditionPathIsMountPoint=</varname></term> - <term><varname>ConditionPathIsReadWrite=</varname></term> - <term><varname>ConditionDirectoryNotEmpty=</varname></term> - <term><varname>ConditionFileNotEmpty=</varname></term> - <term><varname>ConditionFileIsExecutable=</varname></term> - <term><varname>ConditionKernelCommandLine=</varname></term> - <term><varname>ConditionVirtualization=</varname></term> - <term><varname>ConditionSecurity=</varname></term> - <term><varname>ConditionCapability=</varname></term> - <term><varname>ConditionHost=</varname></term> - <term><varname>ConditionACPower=</varname></term> - <term><varname>ConditionNull=</varname></term> - - <listitem><para>Before starting a unit - verify that the specified condition is - true. If it is not true the starting - of the unit will be skipped, however - all ordering dependencies of it are - still respected. A failing condition - will not result in the unit being - moved into a failure state. The - condition is checked at the time the - queued start job is to be - executed.</para> - - <para>With - <varname>ConditionPathExists=</varname> - a file existence condition is - checked before a unit is started. If - the specified absolute path name does - not exist the condition will - fail. If the absolute path name passed - to - <varname>ConditionPathExists=</varname> - is prefixed with an exclamation mark - ('!'), the test is negated, and the unit - is only started if the path does not - exist.</para> - - <para><varname>ConditionPathExistsGlob=</varname> - is similar to - <varname>ConditionPathExists=</varname>, - but checks for the existence of at - least one file or directory matching - the specified globbing pattern.</para> - - <para><varname>ConditionPathIsDirectory=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists and is a - directory.</para> - - <para><varname>ConditionPathIsSymbolicLink=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists and is a symbolic - link.</para> - - <para><varname>ConditionPathIsMountPoint=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists and is a mount - point.</para> - - <para><varname>ConditionPathIsReadWrite=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether the underlying - file system is readable and writable - (i.e. not mounted - read-only).</para> - - <para><varname>ConditionDirectoryNotEmpty=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists and is a non-empty - directory.</para> - - <para><varname>ConditionFileNotEmpty=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists and refers to a regular file - with a non-zero size.</para> - - <para><varname>ConditionFileIsExecutable=</varname> - is similar to - <varname>ConditionPathExists=</varname> - but verifies whether a certain path - exists, is a regular file and marked - executable.</para> - - <para>Similar, - <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 - '='). 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.</para> - - <para><varname>ConditionVirtualization=</varname> - may be used to check whether the - system is executed in a virtualized - environment and optionally test - whether it is a specific - implementation. Takes either boolean - value to check if being executed in - any virtualized environment, or one of - <varname>vm</varname> and - <varname>container</varname> to test - against a generic type of - virtualization solution, or one of - <varname>qemu</varname>, - <varname>kvm</varname>, - <varname>vmware</varname>, - <varname>microsoft</varname>, - <varname>oracle</varname>, - <varname>xen</varname>, - <varname>bochs</varname>, - <varname>chroot</varname>, - <varname>openvz</varname>, - <varname>lxc</varname>, - <varname>lxc-libvirt</varname>, - <varname>systemd-nspawn</varname> to - test against a specific - implementation. If multiple - virtualization technologies are nested - only the innermost is considered. The - test may be negated by prepending an - exclamation mark.</para> - - <para><varname>ConditionSecurity=</varname> - may be used to check whether the given - security module is enabled on the - system. Currently the only recognized - value is <varname>selinux</varname>. - The test may be negated by prepending - an exclamation - mark.</para> - - <para><varname>ConditionCapability=</varname> - may be used to check whether the given - capability exists in the capability - bounding set of the service manager - (i.e. this does not check whether - capability is actually available in - the permitted or effective sets, see - <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry> - for details). Pass a capability name - such as <literal>CAP_MKNOD</literal>, - possibly prefixed with an exclamation - mark to negate the check.</para> - - <para><varname>ConditionHost=</varname> - may be used to match against the - host name or machine ID of the - host. This either takes a host name - string (optionally with shell style - globs) which is tested against the - locally set host name as returned by - <citerefentry><refentrytitle>gethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>, - or a machine ID formatted as string - (see - <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>). - The test may be negated by prepending - an exclamation mark.</para> - - <para><varname>ConditionACPower=</varname> - may be used to check whether the - system has AC power, or is exclusively - battery powered at the time of - activation of the unit. This takes a - boolean argument. If set to - <varname>true</varname> the condition - will hold only if at least one AC - connector of the system is connected - to a power source, or if no AC - connectors are known. Conversely, if - set to <varname>false</varname> the - condition will hold only if there is - at least one AC connector known and - all AC connectors are disconnected - from a power source.</para> - - <para>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.</para> - - <para>If multiple conditions are - specified the unit will be executed if - all of them apply (i.e. a logical AND - is applied). Condition checks can be - prefixed with a pipe symbol (|) in - which case a condition becomes a - triggering condition. If at least one - triggering condition is defined for a - unit then the unit will be executed if - at least one of the triggering - conditions apply and all of the - non-triggering conditions. If you - prefix an argument with the pipe - symbol and an exclamation mark the - pipe symbol must be passed first, the - exclamation second. Except for - <varname>ConditionPathIsSymbolicLink=</varname>, - all path checks follow symlinks. If - any of these options is assigned the - empty string the list of conditions is - reset completely, all previous - condition settings (of any kind) will - have no effect.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>SourcePath=</varname></term> - <listitem><para>A path to a - configuration file this unit has been - generated from. This is primarily - useful for implementation of generator - tools that convert configuration from - an external configuration file format - into native unit files. Thus - functionality should not be used in - normal units.</para></listitem> - </varlistentry> - </variablelist> - - <para>Unit file may include a [Install] section, which - carries installation information for the unit. This - section is not interpreted by - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry> - during runtime. It is used exclusively by the - <command>enable</command> and - <command>disable</command> commands of the - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry> - tool during installation of a unit:</para> - - <variablelist class='unit-directives'> - <varlistentry> - <term><varname>Alias=</varname></term> - - <listitem><para>Additional names this - unit shall be installed under. The - names listed here must have the same - suffix (i.e. type) as the unit file - name. This option may be specified - more than once, in which case all - listed names are used. At installation - time, - <command>systemctl enable</command> - will create symlinks from these names - to the unit file name.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>WantedBy=</varname></term> - <term><varname>RequiredBy=</varname></term> - - <listitem><para>Installs a symlink in - the <filename>.wants/</filename> - or <filename>.requires/</filename> - subdirectory for a unit, respectively. This has the - effect that when the listed unit name - is activated the unit listing it is - activated - too. <command>WantedBy=foo.service</command> - in a service - <filename>bar.service</filename> is - mostly equivalent to - <command>Alias=foo.service.wants/bar.service</command> - in the same file.</para></listitem> - </varlistentry> - - <varlistentry> - <term><varname>Also=</varname></term> - - <listitem><para>Additional units to - install when this unit is - installed. If the user requests - installation of a unit with this - option configured, - <command>systemctl enable</command> - will automatically install units - listed in this option as - well.</para></listitem> - </varlistentry> - </variablelist> - - <para>The following specifiers are interpreted in the - Install section: %n, %N, %p, %i, %U, %u, %m, %H, %b. - For their meaning see the next section. - </para> - </refsect1> - - <refsect1> - <title>Specifiers</title> - - <para>Many settings resolve specifiers which may be - used to write generic unit files referring to runtime - or unit parameters that are replaced when the unit - files are loaded. The following specifiers are - understood:</para> - - <table> - <title>Specifiers available in unit files</title> - <tgroup cols='3' align='left' colsep='1' rowsep='1'> - <colspec colname="spec" /> - <colspec colname="mean" /> - <colspec colname="detail" /> - <thead> - <row> - <entry>Specifier</entry> - <entry>Meaning</entry> - <entry>Details</entry> - </row> - </thead> - <tbody> - <row> - <entry><literal>%n</literal></entry> - <entry>Full unit name</entry> - <entry></entry> - </row> - <row> - <entry><literal>%N</literal></entry> - <entry>Unescaped full unit name</entry> - <entry></entry> - </row> - <row> - <entry><literal>%p</literal></entry> - <entry>Prefix name</entry> - <entry>For instantiated units this refers to the string before the @. For non-instantiated units this refers to to the name of the unit with the type suffix removed.</entry> - </row> - <row> - <entry><literal>%P</literal></entry> - <entry>Unescaped prefix name</entry> - <entry></entry> - </row> - <row> - <entry><literal>%i</literal></entry> - <entry>Instance name</entry> - <entry>For instantiated units: this is the string between the @ character and the suffix.</entry> - </row> - <row> - <entry><literal>%I</literal></entry> - <entry>Unescaped instance name</entry> - <entry></entry> - </row> - <row> - <entry><literal>%f</literal></entry> - <entry>Unescaped file name</entry> - <entry>This is either the unescaped instance name (if applicable) with / prepended (if applicable), or the prefix name similarly prepended with /.</entry> - </row> - <row> - <entry><literal>%c</literal></entry> - <entry>Control group path of the unit</entry> - <entry></entry> - </row> - <row> - <entry><literal>%r</literal></entry> - <entry>Root control group path of systemd</entry> - <entry></entry> - </row> - <row> - <entry><literal>%R</literal></entry> - <entry>Parent directory of the root control group path of systemd</entry> - <entry></entry> - </row> - <row> - <entry><literal>%t</literal></entry> - <entry>Runtime socket dir</entry> - <entry>This is either <filename>/run</filename> (for the system manager) or <literal>$XDG_RUNTIME_DIR</literal> (for user managers).</entry> - </row> - <row> - <entry><literal>%u</literal></entry> - <entry>User name</entry> - <entry>This is the name of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry> - </row> - <row> - <entry><literal>%U</literal></entry> - <entry>User UID</entry> - <entry>This is the UID of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry> - </row> - <row> - <entry><literal>%h</literal></entry> - <entry>User home directory</entry> - <entry>This is the home directory of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry> - </row> - <row> - <entry><literal>%s</literal></entry> - <entry>User shell</entry> - <entry>This is the shell of the configured user of the unit, or (if none is set) the user running the systemd instance.</entry> - </row> - <row> - <entry><literal>%m</literal></entry> - <entry>Machine ID</entry> - <entry>The machine ID of the running system, formatted as string. See <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry> for more information.</entry> - </row> - <row> - <entry><literal>%b</literal></entry> - <entry>Boot ID</entry> - <entry>The boot ID of the running system, formatted as string. See <citerefentry><refentrytitle>random</refentrytitle><manvolnum>4</manvolnum></citerefentry> for more information.</entry> - </row> - <row> - <entry><literal>%H</literal></entry> - <entry>Host name</entry> - <entry>The host name of the running system.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - <title>See Also</title> - <para> - <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.special</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.device</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.mount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.automount</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.swap</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.target</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.path</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.time</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>capabilities</refentrytitle><manvolnum>7</manvolnum></citerefentry>, - <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |