man/systemd-escape.xml

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   8
   9 <refentry id="systemd-escape"
  10     xmlns:xi="http://www.w3.org/2001/XInclude">
  11
  12   <refentryinfo>
  13     <title>systemd-escape</title>
  14     <productname>systemd</productname>
  15   </refentryinfo>
  16
  17   <refmeta>
  18     <refentrytitle>systemd-escape</refentrytitle>
  19     <manvolnum>1</manvolnum>
  20   </refmeta>
  21
  22   <refnamediv>
  23     <refname>systemd-escape</refname>
  24     <refpurpose>Escape strings for usage in systemd unit names</refpurpose>
  25   </refnamediv>
  26
  27   <refsynopsisdiv>
  28     <cmdsynopsis>
  29       <command>systemd-escape</command>
  30       <arg choice="opt" rep="repeat">OPTIONS</arg>
  31       <arg choice="opt" rep="repeat">STRING</arg>
  32     </cmdsynopsis>
  33   </refsynopsisdiv>
  34
  35   <refsect1>
  36     <title>Description</title>
  37
  38     <para><command>systemd-escape</command> may be used to escape
  39     strings for inclusion in systemd unit names. The command may be
  40     used to escape and to undo escaping of strings.</para>
  41
  42     <para>The command takes any number of strings on the command line,
  43     and will process them individually, one after another. It will
  44     output them separated by spaces to stdout.</para>
  45
  46     <para>By default, this command will escape the strings passed,
  47     unless <option>--unescape</option> is passed which results in the
  48     inverse operation being applied. If <option>--mangle</option> is given, a
  49     special mode of escaping is applied instead, which assumes the
  50     string is already escaped but will escape everything that
  51     appears obviously non-escaped.</para>
  52
  53     <para>For details on the escaping and unescaping algorithms see the relevant section in
  54     <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
  55   </refsect1>
  56
  57   <refsect1>
  58     <title>Options</title>
  59
  60     <para>The following options are understood:</para>
  61
  62     <variablelist>
  63       <varlistentry>
  64         <term><option>--suffix=</option></term>
  65
  66         <listitem><para>Appends the specified unit type suffix to the
  67         escaped string. Takes one of the unit types supported by
  68         systemd, such as <literal>service</literal> or
  69         <literal>mount</literal>. May not be used in conjunction with
  70         <option>--template=</option>, <option>--unescape</option> or
  71         <option>--mangle</option>.</para></listitem>
  72       </varlistentry>
  73
  74       <varlistentry>
  75         <term><option>--template=</option></term>
  76
  77         <listitem><para>Inserts the escaped strings in a unit name
  78         template. Takes a unit name template such as
  79         <filename>foobar@.service</filename>. With
  80         <option>--unescape</option>, expects instantiated unit names
  81         for this template and extracts and unescapes just the instance
  82         part. May not be used in conjunction with
  83         <option>--suffix=</option>,
  84         <option>--instance</option> or
  85         <option>--mangle</option>.</para></listitem>
  86       </varlistentry>
  87
  88       <varlistentry>
  89         <term><option>--path</option></term>
  90         <term><option>-p</option></term>
  91
  92         <listitem><para>When escaping or unescaping a string, assume it refers to a file system path. This eliminates
  93         leading, trailing or duplicate <literal>/</literal> characters and rejects <literal>.</literal> and
  94         <literal>..</literal> path components. This is particularly useful for generating strings suitable for
  95         unescaping with the <literal>%f</literal> specifier in unit files, see
  96         <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>.
  97         </para></listitem>
  98       </varlistentry>
  99
 100       <varlistentry>
 101         <term><option>--unescape</option></term>
 102         <term><option>-u</option></term>
 103
 104         <listitem><para>Instead of escaping the specified strings,
 105         undo the escaping, reversing the operation. May not be used in
 106         conjunction with <option>--suffix=</option> or
 107         <option>--mangle</option>.</para></listitem>
 108       </varlistentry>
 109
 110       <varlistentry>
 111         <term><option>--mangle</option></term>
 112         <term><option>-m</option></term>
 113
 114         <listitem><para>Like <option>--escape</option>, but only
 115         escape characters that are obviously not escaped yet, and
 116         possibly automatically append an appropriate unit type suffix
 117         to the string. May not be used in conjunction with
 118         <option>--suffix=</option>, <option>--template=</option> or
 119         <option>--unescape</option>.</para></listitem>
 120       </varlistentry>
 121
 122       <varlistentry>
 123         <term><option>--instance</option></term>
 124
 125         <listitem><para>With <option>--unescape</option>, unescape
 126         and print only the instance part of an instantiated unit name
 127         template. Results in an error for an uninstantiated template
 128         like <filename>ssh@.service</filename> or a non-template name
 129         like <filename>ssh.service</filename>.
 130         Must be used in conjunction with <option>--unescape</option>
 131         and may not be used in conjunction with
 132         <option>--template</option>.</para></listitem>
 133       </varlistentry>
 134
 135       <xi:include href="standard-options.xml" xpointer="help" />
 136       <xi:include href="standard-options.xml" xpointer="version" />
 137     </variablelist>
 138
 139   </refsect1>
 140
 141   <refsect1>
 142     <title>Examples</title>
 143
 144     <para>To escape a single string:</para>
 145     <programlisting>$ systemd-escape 'Hallöchen, Meister'
 146 Hall\xc3\xb6chen\x2c\x20Meister</programlisting>
 147
 148     <para>To undo escaping on a single string:</para>
 149     <programlisting>$ systemd-escape -u 'Hall\xc3\xb6chen\x2c\x20Meister'
 150 Hallöchen, Meister</programlisting>
 151
 152     <para>To generate the mount unit for a path:</para>
 153     <programlisting>$ systemd-escape -p --suffix=mount "/tmp//waldi/foobar/"
 154 tmp-waldi-foobar.mount</programlisting>
 155
 156     <para>To generate instance names of three strings:</para>
 157     <programlisting>$ systemd-escape --template=systemd-nspawn@.service 'My Container 1' 'containerb' 'container/III'
 158 systemd-nspawn@My\x20Container\x201.service systemd-nspawn@containerb.service systemd-nspawn@container-III.service</programlisting>
 159
 160     <para>To extract the instance part of an instantiated unit:</para>
 161     <programlisting>$ systemd-escape -u --instance 'systemd-nspawn@My\x20Container\x201.service'
 162 My Container 1</programlisting>
 163
 164     <para>To extract the instance part of an instance of a particular template:</para>
 165     <programlisting>$ systemd-escape -u --template=systemd-nspawn@.service 'systemd-nspawn@My\x20Container\x201.service'
 166 My Container 1</programlisting>
 167   </refsect1>
 168
 169   <refsect1>
 170     <title>Exit status</title>
 171
 172     <para>On success, 0 is returned, a non-zero failure code
 173     otherwise.</para>
 174   </refsect1>
 175
 176   <refsect1>
 177     <title>See Also</title>
 178     <para>
 179       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 180       <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 181       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 182     </para>
 183   </refsect1>
 184
 185 </refentry>