systemd/man/systemd.path.html
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<a href="../libudev/index.html">gudev </a><span style="float:right">systemd 219</span><hr><div class="refentry"><a name="systemd.path"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>systemd.path — Path unit configuration</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><p><code class="filename"><em class="replaceable"><code>path</code></em>.path</code></p></div><div class="refsect1"><a name="idm140120654431376"></a><h2 id="Description">Description<a class="headerlink" title="Permalink to this headline" href="#Description"></a></h2><p>A unit configuration file whose name ends in
"<code class="literal">.path</code>" encodes information about a path
monitored by systemd, for path-based activation.</p><p>This man page lists the configuration options specific to
this unit type. See
<a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>
for the common options of all unit configuration files. The common
configuration items are configured in the generic [Unit] and
[Install] sections. The path specific configuration options are
configured in the [Path] section.</p><p>For each path file, a matching unit file must exist,
describing the unit to activate when the path changes. By default,
a service by the same name as the path (except for the suffix) is
activated. Example: a path file <code class="filename">foo.path</code>
activates a matching service <code class="filename">foo.service</code>. The
unit to activate may be controlled by <code class="varname">Unit=</code>
(see below).</p><p>Internally, path units use the
<a href="inotify.html"><span class="citerefentry"><span class="refentrytitle">inotify</span>(7)</span></a>
API to monitor file systems. Due to that, it suffers by the same
limitations as inotify, and for example cannot be used to monitor
files or directories changed by other machines on remote NFS file
systems.</p><p>If a path unit is beneath another mount point in the file
system hierarchy, a dependency between both units is created
automatically.</p><p>Unless <code class="varname">DefaultDependencies=false</code> is used,
path units will implicitly have dependencies of type
<code class="varname">Conflicts=</code> and <code class="varname">Before=</code> on
<code class="filename">shutdown.target</code>. These ensure that path units
are terminated cleanly prior to system shutdown. Only path units
involved with early boot or late system shutdown should disable
this option.
</p></div><div class="refsect1"><a name="idm140120654421200"></a><h2 id="Options">Options<a class="headerlink" title="Permalink to this headline" href="#Options"></a></h2><p>Path files must include a [Path] section, which carries
information about the path(s) it monitors. The options specific to
the [Path] section of path units are the following:</p><div class="variablelist"><dl class="variablelist"><dt id="PathExists="><span class="term"><code class="varname">PathExists=</code>, </span><span class="term"><code class="varname">PathExistsGlob=</code>, </span><span class="term"><code class="varname">PathChanged=</code>, </span><span class="term"><code class="varname">PathModified=</code>, </span><span class="term"><code class="varname">DirectoryNotEmpty=</code></span><a class="headerlink" title="Permalink to this term" href="#PathExists="></a></dt><dd><p>Defines paths to monitor for certain changes:
<code class="varname">PathExists=</code> may be used to watch the mere
existence of a file or directory. If the file specified
exists, the configured unit is activated.
<code class="varname">PathExistsGlob=</code> works similar, but checks
for the existence of at least one file matching the globbing
pattern specified. <code class="varname">PathChanged=</code> may be used
to watch a file or directory and activate the configured unit
whenever it changes. It is not activated on every write to the
watched file but it is activated if the file which was open
for writing gets closed. <code class="varname">PathModified=</code> is
similar, but additionally it is activated also on simple
writes to the watched file.
<code class="varname">DirectoryNotEmpty=</code> may be used to watch a
directory and activate the configured unit whenever it
contains at least one file.</p><p>The arguments of these directives must be absolute file
system paths.</p><p>Multiple directives may be combined, of the same and of
different types, to watch multiple paths. If the empty string
is assigned to any of these options, the list of paths to
watch is reset, and any prior assignments of these options
will not have any effect.</p><p>If a path already exists (in case of
<code class="varname">PathExists=</code> and
<code class="varname">PathExistsGlob=</code>) or a directory already is
not empty (in case of <code class="varname">DirectoryNotEmpty=</code>)
at the time the path unit is activated, then the configured
unit is immediately activated as well. Something similar does
not apply to <code class="varname">PathChanged=</code> and
<code class="varname">PathModified=</code>.</p><p>If the path itself or any of the containing directories
are not accessible, <span class="command"><strong>systemd</strong></span> will watch for
permission changes and notice that conditions are satisfied
when permissions allow that. </p></dd><dt id="Unit="><span class="term"><code class="varname">Unit=</code></span><a class="headerlink" title="Permalink to this term" href="#Unit="></a></dt><dd><p>The unit to activate when any of the
configured paths changes. The argument is a unit name, whose
suffix is not "<code class="literal">.path</code>". If not specified, this
value defaults to a service that has the same name as the path
unit, except for the suffix. (See above.) It is recommended
that the unit name that is activated and the unit name of the
path unit are named identical, except for the
suffix.</p></dd><dt id="MakeDirectory="><span class="term"><code class="varname">MakeDirectory=</code></span><a class="headerlink" title="Permalink to this term" href="#MakeDirectory="></a></dt><dd><p>Takes a boolean argument. If true, the
directories to watch are created before watching. This option
is ignored for <code class="varname">PathExists=</code> settings.
Defaults to <code class="option">false</code>.</p></dd><dt id="DirectoryMode="><span class="term"><code class="varname">DirectoryMode=</code></span><a class="headerlink" title="Permalink to this term" href="#DirectoryMode="></a></dt><dd><p>If <code class="varname">MakeDirectory=</code> is
enabled, use the mode specified here to create the directories
in question. Takes an access mode in octal notation. Defaults
to <code class="option">0755</code>.</p></dd></dl></div></div><div class="refsect1"><a name="idm140120658299104"></a><h2 id="See Also">See Also<a class="headerlink" title="Permalink to this headline" href="#See%20Also"></a></h2><p>
<a href="systemd.html"><span class="citerefentry"><span class="refentrytitle">systemd</span>(1)</span></a>,
<a href="systemctl.html"><span class="citerefentry"><span class="refentrytitle">systemctl</span>(1)</span></a>,
<a href="systemd.unit.html"><span class="citerefentry"><span class="refentrytitle">systemd.unit</span>(5)</span></a>,
<a href="systemd.service.html"><span class="citerefentry"><span class="refentrytitle">systemd.service</span>(5)</span></a>,
<a href="inotify.html"><span class="citerefentry"><span class="refentrytitle">inotify</span>(7)</span></a>,
<a href="systemd.directives.html"><span class="citerefentry"><span class="refentrytitle">systemd.directives</span>(7)</span></a>
</p></div></div></body></html>