man/systemd-cat.xml

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   8   This file is part of systemd.
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  10   Copyright 2012 Lennart Poettering
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  25
  26 <refentry id="systemd-cat"
  27     xmlns:xi="http://www.w3.org/2001/XInclude">
  28
  29   <refentryinfo>
  30     <title>systemd-cat</title>
  31     <productname>systemd</productname>
  32
  33     <authorgroup>
  34       <author>
  35         <contrib>Developer</contrib>
  36         <firstname>Lennart</firstname>
  37         <surname>Poettering</surname>
  38         <email>lennart@poettering.net</email>
  39       </author>
  40     </authorgroup>
  41   </refentryinfo>
  42
  43   <refmeta>
  44     <refentrytitle>systemd-cat</refentrytitle>
  45     <manvolnum>1</manvolnum>
  46   </refmeta>
  47
  48   <refnamediv>
  49     <refname>systemd-cat</refname>
  50     <refpurpose>Connect a pipeline or program's output with the journal</refpurpose>
  51   </refnamediv>
  52
  53   <refsynopsisdiv>
  54     <cmdsynopsis>
  55       <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg> <arg>COMMAND</arg> <arg choice="opt" rep="repeat">ARGUMENTS</arg></command>
  56     </cmdsynopsis>
  57     <cmdsynopsis>
  58       <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg></command>
  59     </cmdsynopsis>
  60   </refsynopsisdiv>
  61
  62   <refsect1>
  63     <title>Description</title>
  64
  65     <para><command>systemd-cat</command> may be used to connect the
  66     standard input and output of a process to the journal, or as a
  67     filter tool in a shell pipeline to pass the output the previous
  68     pipeline element generates to the journal.</para>
  69
  70     <para>If no parameter is passed, <command>systemd-cat</command>
  71     will write everything it reads from standard input (stdin) to the
  72     journal.</para>
  73
  74     <para>If parameters are passed, they are executed as command line
  75     with standard output (stdout) and standard error output (stderr)
  76     connected to the journal, so that all it writes is stored in the
  77     journal.</para>
  78   </refsect1>
  79
  80   <refsect1>
  81     <title>Options</title>
  82
  83     <para>The following options are understood:</para>
  84
  85     <variablelist>
  86       <xi:include href="standard-options.xml" xpointer="help" />
  87       <xi:include href="standard-options.xml" xpointer="version" />
  88
  89       <varlistentry>
  90         <term><option>-t</option></term>
  91         <term><option>--identifier=</option></term>
  92
  93         <listitem><para>Specify a short string that is used to
  94         identify the logging tool. If not specified, no identification
  95         string is written to the journal.</para></listitem>
  96       </varlistentry>
  97
  98       <varlistentry>
  99         <term><option>-p</option></term>
 100         <term><option>--priority=</option></term>
 101
 102         <listitem><para>Specify the default priority level for the
 103         logged messages. Pass one of
 104         <literal>emerg</literal>,
 105         <literal>alert</literal>,
 106         <literal>crit</literal>,
 107         <literal>err</literal>,
 108         <literal>warning</literal>,
 109         <literal>notice</literal>,
 110         <literal>info</literal>,
 111         <literal>debug</literal>, or a
 112         value between 0 and 7 (corresponding to the same named
 113         levels). These priority values are the same as defined by
 114         <citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 115         Defaults to <literal>info</literal>. Note that this simply
 116         controls the default, individual lines may be logged with
 117         different levels if they are prefixed accordingly. For details,
 118         see <option>--level-prefix=</option> below.</para></listitem>
 119       </varlistentry>
 120
 121       <varlistentry>
 122         <term><option>--level-prefix=</option></term>
 123
 124         <listitem><para>Controls whether lines read are parsed for
 125         syslog priority level prefixes. If enabled (the default), a
 126         line prefixed with a priority prefix such as
 127         <literal>&lt;5&gt;</literal> is logged at priority 5
 128         (<literal>notice</literal>), and similar for the other
 129         priority levels. Takes a boolean argument.</para></listitem>
 130       </varlistentry>
 131
 132     </variablelist>
 133
 134   </refsect1>
 135
 136   <refsect1>
 137     <title>Exit status</title>
 138
 139     <para>On success, 0 is returned, a non-zero failure code
 140     otherwise.</para>
 141   </refsect1>
 142
 143   <refsect1>
 144     <title>Examples</title>
 145
 146     <example>
 147       <title>Invoke a program</title>
 148
 149       <para>This calls <filename noindex='true'>/bin/ls</filename>
 150       with standard output and error connected to the journal:</para>
 151
 152       <programlisting># systemd-cat ls</programlisting>
 153     </example>
 154
 155     <example>
 156       <title>Usage in a shell pipeline</title>
 157
 158       <para>This builds a shell pipeline also invoking
 159       <filename>/bin/ls</filename> and writes the output it generates
 160       to the journal:</para>
 161
 162       <programlisting># ls | systemd-cat</programlisting>
 163     </example>
 164
 165     <para>Even though the two examples have very similar effects the
 166     first is preferable since only one process is running at a time,
 167     and both stdout and stderr are captured while in the second
 168     example, only stdout is captured.</para>
 169   </refsect1>
 170
 171   <refsect1>
 172     <title>See Also</title>
 173     <para>
 174       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 175       <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 176       <citerefentry project='man-pages'><refentrytitle>logger</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 177     </para>
 178   </refsect1>
 179
 180 </refentry>