chiark / gitweb /
journald: move /dev/log socket to /run
[elogind.git] / man / systemd.path.xml
index 44f536c..8d86fca 100644 (file)
@@ -9,16 +9,16 @@
   Copyright 2010 Lennart Poettering
 
   systemd is free software; you can redistribute it and/or modify it
-  under the terms of the GNU General Public License as published by
-  the Free Software Foundation; either version 2 of the License, or
+  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
-  General Public License for more details.
+  Lesser General Public License for more details.
 
-  You should have received a copy of the GNU General Public License
+  You should have received a copy of the GNU Lesser General Public License
   along with systemd; If not, see <http://www.gnu.org/licenses/>.
 -->
 
 
         <refnamediv>
                 <refname>systemd.path</refname>
-                <refpurpose>systemd path configuration files</refpurpose>
+                <refpurpose>Path unit configuration</refpurpose>
         </refnamediv>
 
         <refsynopsisdiv>
-                <para><filename>systemd.path</filename></para>
+                <para><filename><replaceable>path</replaceable>.path</filename></para>
         </refsynopsisdiv>
 
         <refsect1>
                 <title>Description</title>
 
                 <para>A unit configuration file whose name ends in
-                <filename>.path</filename> encodes information about
+                <literal>.path</literal> encodes information about
                 a path monitored by systemd, for
                 path-based activation.</para>
 
@@ -68,9 +68,9 @@
                 path specific configuration options are configured in
                 the [Path] section.</para>
 
-                <para>For each path file a matching unit file must
+                <para>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
+                changes. By default, a service by the same name as the
                 path (except for the suffix) is activated. Example: a
                 path file <filename>foo.path</filename> activates a
                 matching service <filename>foo.service</filename>. The
 
                 <para>Internally, path units use the
                 <citerefentry><refentrytitle>inotify</refentrytitle><manvolnum>7</manvolnum></citerefentry>
-                API to monitor file systems. Due to that it suffers by the
+                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.</para>
 
-                <para>If an path unit is beneath another mount
-                point in the file system hierarchy a dependency
+                <para>If a path unit is beneath another mount
+                point in the file system hierarchy, a dependency
                 between both units is created automatically.</para>
+
+                <para>Unless <varname>DefaultDependencies=false</varname>
+                is used, path units will implicitly have dependencies of
+                type <varname>Conflicts=</varname> and
+                <varname>Before=</varname> on
+                <filename>shutdown.target</filename>. 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.
+                </para>
         </refsect1>
 
         <refsect1>
                 monitors. The options specific to the [Path] section
                 of path units are the following:</para>
 
-                <variablelist>
+                <variablelist class='unit-directives'>
                         <varlistentry>
                                 <term><varname>PathExists=</varname></term>
+                                <term><varname>PathExistsGlob=</varname></term>
                                 <term><varname>PathChanged=</varname></term>
+                                <term><varname>PathModified=</varname></term>
                                 <term><varname>DirectoryNotEmpty=</varname></term>
 
                                 <listitem><para>Defines paths to
                                 monitor for certain changes:
                                 <varname>PathExists=</varname> may be
-                                used to watch the mere existance of a
+                                used to watch the mere existence of a
                                 file or directory. If the file
-                                specified exists the configured unit
+                                specified exists, the configured unit
                                 is
-                                activated. <varname>PathChanged=</varname>
+                                activated. <varname>PathExistsGlob=</varname>
+                                works similar, but checks for the
+                                existence of at least one file
+                                matching the globbing pattern
+                                specified. <varname>PathChanged=</varname>
                                 may be used to watch a file or
                                 directory and activate the configured
-                                unit whenever it changes or is
-                                modified. <varname>DirectoryNotEmpty=</varname>
+                                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. <varname>PathModified=</varname>
+                                is similar, but additionally it is
+                                activated also on simple writes to the
+                                watched file.
+                                <varname>DirectoryNotEmpty=</varname>
                                 may be used to watch a directory and
-                                activate the configured unit whenver
+                                activate the configured unit whenever
                                 it contains at least one file.</para>
 
                                 <para>The arguments of these
 
                                 <para>Multiple directives may be
                                 combined, of the same and of different
-                                types, to watch multiple paths.</para>
-
-                                <para>If a path is already existing
+                                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.</para>
+
+                                <para>If a path already exists
                                 (in case of
-                                <varname>PathExists=</varname>) or a
-                                directory already is not empty (in
+                                <varname>PathExists=</varname> and
+                                <varname>PathExistsGlob=</varname>) or
+                                a directory already is not empty (in
                                 case of
                                 <varname>DirectoryNotEmpty=</varname>)
-                                at the time the path unit is activated
-                                then the configured unit is
+                                at the time the path unit is
+                                activated, then the configured unit is
                                 immediately activated as
                                 well. Something similar does not apply
-                                to <varname>PathChanged=</varname>.
+                                to <varname>PathChanged=</varname> and
+                                <varname>PathModified=</varname>.</para>
+
+                                <para>If the path itself or any of the
+                                containing directories are not
+                                accessible, <command>systemd</command>
+                                will watch for permission changes and
+                                notice that conditions are satisfied
+                                when permissions allow that.
                                 </para></listitem>
                         </varlistentry>
                         <varlistentry>
                                 when any of the configured paths
                                 changes. The argument is a unit name,
                                 whose suffix is not
-                                <filename>.path</filename>. If not
-                                specified this value defaults to a
+                                <literal>.path</literal>. 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 is chosen
-                                identical except for the
+                                unit name of the path unit are named
+                                identical, except for the
                                 suffix.</para></listitem>
                         </varlistentry>
+                        <varlistentry>
+                                <term><varname>MakeDirectory=</varname></term>
+
+                                <listitem><para>Takes a boolean
+                                argument. If true, the directories to
+                                watch are created before
+                                watching. This option is ignored for
+                                <varname>PathExists=</varname>
+                                settings. Defaults to
+                                <option>false</option>.</para></listitem>
+                        </varlistentry>
+                        <varlistentry>
+                                <term><varname>DirectoryMode=</varname></term>
+
+                                <listitem><para>If
+                                <varname>MakeDirectory=</varname> is
+                                enabled, use the mode specified here to
+                                create the directories in
+                                question. Takes an access mode in
+                                octal notation. Defaults to
+                                <option>0755</option>.</para></listitem>
+                        </varlistentry>
                 </variablelist>
         </refsect1>
 
         <refsect1>
                   <title>See Also</title>
                   <para>
-                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                          <citerefentry><refentrytitle>inotify</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>inotify</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd.directives</refentrytitle><manvolnum>7</manvolnum></citerefentry>
                   </para>
         </refsect1>