systemd/man/systemd-escape.xml
2020-11-09 13:23:58 +09:00

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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
<refentry id="systemd-escape"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-escape</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-escape</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-escape</refname>
<refpurpose>Escape strings for usage in systemd unit names</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>systemd-escape</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
<arg choice="opt" rep="repeat">STRING</arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>systemd-escape</command> may be used to escape
strings for inclusion in systemd unit names. The command may be
used to escape and to undo escaping of strings.</para>
<para>The command takes any number of strings on the command line,
and will process them individually, one after another. It will
output them separated by spaces to stdout.</para>
<para>By default, this command will escape the strings passed,
unless <option>--unescape</option> is passed which results in the
inverse operation being applied. If <option>--mangle</option> is given, a
special mode of escaping is applied instead, which assumes the
string is already escaped but will escape everything that
appears obviously non-escaped.</para>
<para>For details on the escaping and unescaping algorithms see the relevant section in
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<varlistentry>
<term><option>--suffix=</option></term>
<listitem><para>Appends the specified unit type suffix to the
escaped string. Takes one of the unit types supported by
systemd, such as <literal>service</literal> or
<literal>mount</literal>. May not be used in conjunction with
<option>--template=</option>, <option>--unescape</option> or
<option>--mangle</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--template=</option></term>
<listitem><para>Inserts the escaped strings in a unit name
template. Takes a unit name template such as
<filename>foobar@.service</filename>. With
<option>--unescape</option>, expects instantiated unit names
for this template and extracts and unescapes just the instance
part. May not be used in conjunction with
<option>--suffix=</option>,
<option>--instance</option> or
<option>--mangle</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--path</option></term>
<term><option>-p</option></term>
<listitem><para>When escaping or unescaping a string, assume it refers to a file system path. This eliminates
leading, trailing or duplicate <literal>/</literal> characters and rejects <literal>.</literal> and
<literal>..</literal> path components. This is particularly useful for generating strings suitable for
unescaping with the <literal>%f</literal> specifier in unit files, see
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--unescape</option></term>
<term><option>-u</option></term>
<listitem><para>Instead of escaping the specified strings,
undo the escaping, reversing the operation. May not be used in
conjunction with <option>--suffix=</option> or
<option>--mangle</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--mangle</option></term>
<term><option>-m</option></term>
<listitem><para>Like <option>--escape</option>, but only
escape characters that are obviously not escaped yet, and
possibly automatically append an appropriate unit type suffix
to the string. May not be used in conjunction with
<option>--suffix=</option>, <option>--template=</option> or
<option>--unescape</option>.</para></listitem>
</varlistentry>
<varlistentry>
<term><option>--instance</option></term>
<listitem><para>With <option>--unescape</option>, unescape
and print only the instance part of an instantiated unit name
template. Results in an error for an uninstantiated template
like <filename>ssh@.service</filename> or a non-template name
like <filename>ssh.service</filename>.
Must be used in conjunction with <option>--unescape</option>
and may not be used in conjunction with
<option>--template</option>.</para></listitem>
</varlistentry>
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</refsect1>
<refsect1>
<title>Examples</title>
<para>To escape a single string:</para>
<programlisting>$ systemd-escape 'Hallöchen, Meister'
Hall\xc3\xb6chen\x2c\x20Meister</programlisting>
<para>To undo escaping on a single string:</para>
<programlisting>$ systemd-escape -u 'Hall\xc3\xb6chen\x2c\x20Meister'
Hallöchen, Meister</programlisting>
<para>To generate the mount unit for a path:</para>
<programlisting>$ systemd-escape -p --suffix=mount "/tmp//waldi/foobar/"
tmp-waldi-foobar.mount</programlisting>
<para>To generate instance names of three strings:</para>
<programlisting>$ systemd-escape --template=systemd-nspawn@.service 'My Container 1' 'containerb' 'container/III'
systemd-nspawn@My\x20Container\x201.service systemd-nspawn@containerb.service systemd-nspawn@container-III.service</programlisting>
<para>To extract the instance part of an instantiated unit:</para>
<programlisting>$ systemd-escape -u --instance 'systemd-nspawn@My\x20Container\x201.service'
My Container 1</programlisting>
<para>To extract the instance part of an instance of a particular template:</para>
<programlisting>$ systemd-escape -u --template=systemd-nspawn@.service 'systemd-nspawn@My\x20Container\x201.service'
My Container 1</programlisting>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, a non-zero failure code
otherwise.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
<citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>