man/systemd-cat.xml

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   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
   7 -->
   8
   9 <refentry id="systemd-cat"
  10     xmlns:xi="http://www.w3.org/2001/XInclude">
  11
  12   <refentryinfo>
  13     <title>systemd-cat</title>
  14     <productname>systemd</productname>
  15
  16     <authorgroup>
  17       <author>
  18         <contrib>Developer</contrib>
  19         <firstname>Lennart</firstname>
  20         <surname>Poettering</surname>
  21         <email>lennart@poettering.net</email>
  22       </author>
  23     </authorgroup>
  24   </refentryinfo>
  25
  26   <refmeta>
  27     <refentrytitle>systemd-cat</refentrytitle>
  28     <manvolnum>1</manvolnum>
  29   </refmeta>
  30
  31   <refnamediv>
  32     <refname>systemd-cat</refname>
  33     <refpurpose>Connect a pipeline or program's output with the journal</refpurpose>
  34   </refnamediv>
  35
  36   <refsynopsisdiv>
  37     <cmdsynopsis>
  38       <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg> <arg>COMMAND</arg> <arg choice="opt" rep="repeat">ARGUMENTS</arg></command>
  39     </cmdsynopsis>
  40     <cmdsynopsis>
  41       <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg></command>
  42     </cmdsynopsis>
  43   </refsynopsisdiv>
  44
  45   <refsect1>
  46     <title>Description</title>
  47
  48     <para><command>systemd-cat</command> may be used to connect the
  49     standard input and output of a process to the journal, or as a
  50     filter tool in a shell pipeline to pass the output the previous
  51     pipeline element generates to the journal.</para>
  52
  53     <para>If no parameter is passed, <command>systemd-cat</command>
  54     will write everything it reads from standard input (stdin) to the
  55     journal.</para>
  56
  57     <para>If parameters are passed, they are executed as command line
  58     with standard output (stdout) and standard error output (stderr)
  59     connected to the journal, so that all it writes is stored in the
  60     journal.</para>
  61   </refsect1>
  62
  63   <refsect1>
  64     <title>Options</title>
  65
  66     <para>The following options are understood:</para>
  67
  68     <variablelist>
  69       <xi:include href="standard-options.xml" xpointer="help" />
  70       <xi:include href="standard-options.xml" xpointer="version" />
  71
  72       <varlistentry>
  73         <term><option>-t</option></term>
  74         <term><option>--identifier=</option></term>
  75
  76         <listitem><para>Specify a short string that is used to
  77         identify the logging tool. If not specified, no identification
  78         string is written to the journal.</para></listitem>
  79       </varlistentry>
  80
  81       <varlistentry>
  82         <term><option>-p</option></term>
  83         <term><option>--priority=</option></term>
  84
  85         <listitem><para>Specify the default priority level for the
  86         logged messages. Pass one of
  87         <literal>emerg</literal>,
  88         <literal>alert</literal>,
  89         <literal>crit</literal>,
  90         <literal>err</literal>,
  91         <literal>warning</literal>,
  92         <literal>notice</literal>,
  93         <literal>info</literal>,
  94         <literal>debug</literal>, or a
  95         value between 0 and 7 (corresponding to the same named
  96         levels). These priority values are the same as defined by
  97         <citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
  98         Defaults to <literal>info</literal>. Note that this simply
  99         controls the default, individual lines may be logged with
 100         different levels if they are prefixed accordingly. For details,
 101         see <option>--level-prefix=</option> below.</para></listitem>
 102       </varlistentry>
 103
 104       <varlistentry>
 105         <term><option>--level-prefix=</option></term>
 106
 107         <listitem><para>Controls whether lines read are parsed for
 108         syslog priority level prefixes. If enabled (the default), a
 109         line prefixed with a priority prefix such as
 110         <literal>&lt;5&gt;</literal> is logged at priority 5
 111         (<literal>notice</literal>), and similar for the other
 112         priority levels. Takes a boolean argument.</para></listitem>
 113       </varlistentry>
 114
 115     </variablelist>
 116
 117   </refsect1>
 118
 119   <refsect1>
 120     <title>Exit status</title>
 121
 122     <para>On success, 0 is returned, a non-zero failure code
 123     otherwise.</para>
 124   </refsect1>
 125
 126   <refsect1>
 127     <title>Examples</title>
 128
 129     <example>
 130       <title>Invoke a program</title>
 131
 132       <para>This calls <filename noindex='true'>/bin/ls</filename>
 133       with standard output and error connected to the journal:</para>
 134
 135       <programlisting># systemd-cat ls</programlisting>
 136     </example>
 137
 138     <example>
 139       <title>Usage in a shell pipeline</title>
 140
 141       <para>This builds a shell pipeline also invoking
 142       <filename>/bin/ls</filename> and writes the output it generates
 143       to the journal:</para>
 144
 145       <programlisting># ls | systemd-cat</programlisting>
 146     </example>
 147
 148     <para>Even though the two examples have very similar effects the
 149     first is preferable since only one process is running at a time,
 150     and both stdout and stderr are captured while in the second
 151     example, only stdout is captured.</para>
 152   </refsect1>
 153
 154   <refsect1>
 155     <title>See Also</title>
 156     <para>
 157       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 158       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 159       <citerefentry project='man-pages'><refentrytitle>logger</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 160     </para>
 161   </refsect1>
 162
 163 </refentry>