X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=man%2Fsystemd.unit.xml;h=a06eed58618011b1225d589185af682bb4dc32c2;hb=b3eaa6288107210a84d6d121036fb4b2f7283ee2;hp=8a402d053d9a6e100cf60e2bd12c62fb12086981;hpb=af62c704053b5d34672497eb5bdc4764ebbb5f4f;p=elogind.git

diff --git a/man/systemd.unit.xml b/man/systemd.unit.xml
index 8a402d053..a06eed586 100644
--- a/man/systemd.unit.xml
+++ b/man/systemd.unit.xml
@@ -56,7 +56,8 @@
                 <filename>systemd.swap</filename>,
                 <filename>systemd.target</filename>,
                 <filename>systemd.path</filename>,
-                <filename>systemd.timer</filename></para>
+                <filename>systemd.timer</filename>,
+                <filename>systemd.snapshot</filename></para>
         </refsynopsisdiv>
 
         <refsect1>
@@ -70,7 +71,7 @@
                 <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 Specificiation</ulink> <filename>.desktop</filename> files, which are in turn
+                Desktop Entry Specification</ulink> <filename>.desktop</filename> files, which are in turn
                 inspired by Microsoft Windows
                 <filename>.ini</filename> files.</para>
 
@@ -94,7 +95,7 @@
                 additional information in the unit files.</para>
 
                 <para>Boolean arguments used in unit files can be
-                written in various forms. For positive settings the
+                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
@@ -102,8 +103,21 @@
                 <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 value 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.</para>
+
                 <para>Empty lines and lines starting with # or ; are
-                ignored. This may be used for commenting.</para>
+                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>If a line starts with <option>.include</option>
                 followed by a file name the specified file will be
@@ -134,6 +148,47 @@
                 activation which makes dependencies implicit, which
                 both results in a 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 it 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. 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. 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>
         </refsect1>
 
         <refsect1>
@@ -163,10 +218,10 @@
                         <varlistentry>
                                 <term><varname>Description=</varname></term>
                                 <listitem><para>A free-form string
-                                describing the unit. This is intended for use
-                                in UIs wanting to show
-                                descriptive information along with the
-                                unit name.</para></listitem>
+                                describing the unit. This is intended
+                                for use in UIs to show descriptive
+                                information along with the unit
+                                name.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
@@ -227,7 +282,7 @@
                                 must be fulfilled and otherwise the
                                 transaction fails. Hence, this option
                                 may be used to configure dependencies
-                                that are normally honoured unless the
+                                that are normally honored unless the
                                 user explicitly starts up the unit, in
                                 which case whether they failed or not
                                 is irrelevant.</para></listitem>
@@ -393,12 +448,40 @@
                                 dependency of another unit start-up
                                 will succeed. This is mostly a safety
                                 feature to ensure that the user does
-                                not accidently activate units that are
+                                not accidentally activate units that are
                                 not intended to be activated
                                 explicitly. 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
+                                complete 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>
+
                 </variablelist>
 
                 <para>Unit file may include a [Install] section, which
@@ -413,7 +496,7 @@
                         <varlistentry>
                                 <term><varname>Alias=</varname></term>
 
-                                <listitem><para>Additional names, this
+                                <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
@@ -458,7 +541,7 @@
                                 effect that when the listed unit name
                                 is activated the unit listing it is
                                 activated
-                                to. <command>WantedBy=foo.service</command>
+                                too. <command>WantedBy=foo.service</command>
                                 in a service
                                 <filename>bar.service</filename> is
                                 mostly equivalent to
@@ -498,7 +581,8 @@
                         <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.timer</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>systemd.snapshot</refentrytitle><manvolnum>5</manvolnum></citerefentry>
                 </para>
         </refsect1>