man/systemd-cat.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3         "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
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   6   This file is part of systemd.
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   8   Copyright 2012 Lennart Poettering
   9
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  23
  24 <refentry id="systemd-cat"
  25           xmlns:xi="http://www.w3.org/2001/XInclude">
  26
  27         <refentryinfo>
  28                 <title>systemd-cat</title>
  29                 <productname>systemd</productname>
  30
  31                 <authorgroup>
  32                         <author>
  33                                 <contrib>Developer</contrib>
  34                                 <firstname>Lennart</firstname>
  35                                 <surname>Poettering</surname>
  36                                 <email>lennart@poettering.net</email>
  37                         </author>
  38                 </authorgroup>
  39         </refentryinfo>
  40
  41         <refmeta>
  42                 <refentrytitle>systemd-cat</refentrytitle>
  43                 <manvolnum>1</manvolnum>
  44         </refmeta>
  45
  46         <refnamediv>
  47                 <refname>systemd-cat</refname>
  48                 <refpurpose>Connect a pipeline or program's output with the journal</refpurpose>
  49         </refnamediv>
  50
  51         <refsynopsisdiv>
  52                 <cmdsynopsis>
  53                         <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg> <arg>COMMAND</arg> <arg choice="opt" rep="repeat">ARGUMENTS</arg></command>
  54                 </cmdsynopsis>
  55                 <cmdsynopsis>
  56                         <command>systemd-cat <arg choice="opt" rep="repeat">OPTIONS</arg></command>
  57                 </cmdsynopsis>
  58         </refsynopsisdiv>
  59
  60         <refsect1>
  61                 <title>Description</title>
  62
  63                 <para><command>systemd-cat</command> may be used to
  64                 connect the standard input and output of a process to the
  65                 journal, or as a filter tool in a shell pipeline to
  66                 pass the output the previous pipeline element
  67                 generates to the journal.</para>
  68
  69                 <para>If no parameter is passed,
  70                 <command>systemd-cat</command> will write
  71                 everything it reads from standard input (stdin) to the journal.</para>
  72
  73                 <para>If parameters are passed, they are executed as
  74                 command line with standard output (stdout) and standard
  75                 error output (stderr) connected to the journal, so
  76                 that all it writes is stored in the journal.</para>
  77         </refsect1>
  78
  79         <refsect1>
  80                 <title>Options</title>
  81
  82                 <para>The following options are understood:</para>
  83
  84                 <variablelist>
  85                         <xi:include href="standard-options.xml" xpointer="help" />
  86                         <xi:include href="standard-options.xml" xpointer="version" />
  87
  88                         <varlistentry>
  89                                 <term><option>-t</option></term>
  90                                 <term><option>--identifier=</option></term>
  91
  92                                 <listitem><para>Specify a short string
  93                                 that is used to identify the logging
  94                                 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
 103                                 priority level for the logged
 104                                 messages. Pass one of
 105                                 <literal>emerg</literal>,
 106                                 <literal>alert</literal>,
 107                                 <literal>crit</literal>,
 108                                 <literal>err</literal>,
 109                                 <literal>warning</literal>,
 110                                 <literal>notice</literal>,
 111                                 <literal>info</literal>,
 112                                 <literal>debug</literal>, or a
 113                                 value between 0 and 7 (corresponding
 114                                 to the same named levels). These
 115                                 priority values are the same as
 116                                 defined by
 117                                 <citerefentry project='man-pages'><refentrytitle>syslog</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Defaults
 118                                 to <literal>info</literal>. Note that
 119                                 this simply controls the default,
 120                                 individual lines may be logged with
 121                                 different levels if they are prefixed
 122                                 accordingly. For details see
 123                                 <option>--level-prefix=</option>
 124                                 below.</para></listitem>
 125                         </varlistentry>
 126
 127                         <varlistentry>
 128                                 <term><option>--level-prefix=</option></term>
 129
 130                                 <listitem><para>Controls whether lines
 131                                 read are parsed for syslog priority
 132                                 level prefixes. If enabled (the
 133                                 default), a line prefixed with a
 134                                 priority prefix such as
 135                                 <literal>&lt;5&gt;</literal> is logged
 136                                 at priority 5
 137                                 (<literal>notice</literal>), and
 138                                 similar for the other priority
 139                                 levels. Takes a boolean
 140                                 argument.</para></listitem>
 141                         </varlistentry>
 142
 143                 </variablelist>
 144
 145         </refsect1>
 146
 147         <refsect1>
 148                 <title>Exit status</title>
 149
 150                 <para>On success, 0 is returned, a non-zero failure
 151                 code otherwise.</para>
 152         </refsect1>
 153
 154         <refsect1>
 155                 <title>Examples</title>
 156
 157                 <example>
 158                         <title>Invoke a program</title>
 159
 160                         <para>This calls <filename noindex='true'>/bin/ls</filename>
 161                         with standard output and error connected to the
 162                         journal:</para>
 163
 164                         <programlisting># systemd-cat ls</programlisting>
 165                 </example>
 166
 167                 <example>
 168                         <title>Usage in a shell pipeline</title>
 169
 170                         <para>This builds a shell pipeline also
 171                         invoking <filename>/bin/ls</filename> and
 172                         writes the output it generates to the
 173                         journal:</para>
 174
 175                         <programlisting># ls | systemd-cat</programlisting>
 176                 </example>
 177
 178                 <para>Even though the two examples have very similar
 179                 effects the first is preferable since only one process
 180                 is running at a time, and both stdout and stderr are
 181                 captured while in the second example, only stdout is
 182                 captured.</para>
 183         </refsect1>
 184
 185         <refsect1>
 186                 <title>See Also</title>
 187                 <para>
 188                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 189                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 190                         <citerefentry><refentrytitle>logger</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 191                 </para>
 192         </refsect1>
 193
 194 </refentry>