man/systemd-socket-activate.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   Copyright 2013 Zbigniew Jędrzejewski-Szmek
   9 -->
  10
  11 <refentry id="systemd-socket-activate"
  12           xmlns:xi="http://www.w3.org/2001/XInclude">
  13
  14   <refentryinfo>
  15     <title>systemd-socket-activate</title>
  16     <productname>systemd</productname>
  17
  18     <authorgroup>
  19       <author>
  20         <contrib>Developer</contrib>
  21         <firstname>Zbigniew</firstname>
  22         <surname>Jędrzejewski-Szmek</surname>
  23         <email>zbyszek@in.waw.pl</email>
  24       </author>
  25     </authorgroup>
  26   </refentryinfo>
  27
  28   <refmeta>
  29     <refentrytitle>systemd-socket-activate</refentrytitle>
  30     <manvolnum>1</manvolnum>
  31   </refmeta>
  32
  33   <refnamediv>
  34     <refname>systemd-socket-activate</refname>
  35     <refpurpose>Test socket activation of daemons</refpurpose>
  36   </refnamediv>
  37
  38   <refsynopsisdiv>
  39     <cmdsynopsis>
  40       <command>systemd-socket-activate</command>
  41       <arg choice="opt" rep="repeat">OPTIONS</arg>
  42       <arg choice="plain"><replaceable>daemon</replaceable></arg>
  43       <arg choice="opt" rep="repeat">OPTIONS</arg>
  44     </cmdsynopsis>
  45   </refsynopsisdiv>
  46
  47   <refsect1>
  48     <title>Description</title>
  49
  50     <para><command>systemd-socket-activate</command> may be used to launch a socket-activated service program from the
  51     command line for testing purposes. It may also be used to launch individual instances of the service program per
  52     connection.
  53     </para>
  54
  55     <para>The daemon to launch and its options should be specified
  56     after options intended for <command>systemd-socket-activate</command>.
  57     </para>
  58
  59     <para>If the <option>--inetd</option> option is given, the socket file descriptor will be used as the standard
  60     input and output of the launched process. Otherwise, standard input and output will be inherited, and sockets will
  61     be passed through file descriptors 3 and higher. Sockets passed through <varname>$LISTEN_FDS</varname> to
  62     <command>systemd-socket-activate</command> will be passed through to the daemon, in the original positions. Other sockets
  63     specified with <option>--listen=</option> will use consecutive descriptors.  By default,
  64     <command>systemd-socket-activate</command> listens on a stream socket, use <option>--datagram</option> and
  65     <option>--seqpacket</option> to listen on datagram or sequential packet sockets instead (see below).
  66     </para>
  67   </refsect1>
  68
  69   <refsect1>
  70     <title>Options</title>
  71     <variablelist>
  72       <varlistentry>
  73         <term><option>-l <replaceable>address</replaceable></option></term>
  74         <term><option>--listen=<replaceable>address</replaceable></option></term>
  75
  76         <listitem><para>Listen on this <replaceable>address</replaceable>.
  77         Takes a string like <literal>2000</literal> or
  78         <literal>127.0.0.1:2001</literal>.</para>
  79         </listitem>
  80       </varlistentry>
  81
  82       <varlistentry>
  83         <term><option>-a</option></term>
  84         <term><option>--accept</option></term>
  85
  86         <listitem><para>Launch an instance of the service program for each connection and pass the connection
  87         socket.</para></listitem>
  88       </varlistentry>
  89
  90       <varlistentry>
  91         <term><option>-d</option></term>
  92         <term><option>--datagram</option></term>
  93
  94         <listitem><para>Listen on a datagram socket (<constant>SOCK_DGRAM</constant>), instead of a stream socket
  95         (<constant>SOCK_STREAM</constant>). May not be combined with <option>--seqpacket</option>.</para></listitem>
  96       </varlistentry>
  97
  98       <varlistentry>
  99         <term><option>--seqpacket</option></term>
 100
 101         <listitem><para>Listen on a sequential packet socket (<constant>SOCK_SEQPACKET</constant>), instead of a stream
 102         socket (<constant>SOCK_STREAM</constant>). May not be combined with
 103         <option>--datagram</option>.</para></listitem>
 104       </varlistentry>
 105
 106       <varlistentry>
 107         <term><option>--inetd</option></term>
 108
 109         <listitem><para>Use the inetd protocol for passing file descriptors, i.e. as standard input and standard
 110         output, instead of the new-style protocol for passing file descriptors using <varname>$LISTEN_FDS</varname>
 111         (see above).</para></listitem>
 112       </varlistentry>
 113
 114       <varlistentry>
 115         <term><option>-E <replaceable>VAR</replaceable><optional>=<replaceable>VALUE</replaceable></optional></option></term>
 116         <term><option>--setenv=<replaceable>VAR</replaceable><optional>=<replaceable>VALUE</replaceable></optional></option></term>
 117
 118         <listitem><para>Add this variable to the environment of the
 119         launched process. If <replaceable>VAR</replaceable> is
 120         followed by <literal>=</literal>, assume that it is a
 121         variable–value pair. Otherwise, obtain the value from the
 122         environment of <command>systemd-socket-activate</command> itself.
 123         </para></listitem>
 124       </varlistentry>
 125
 126       <varlistentry>
 127         <term><option>--fdname=</option><replaceable>NAME</replaceable><optional>:<replaceable>NAME</replaceable>…</optional></term>
 128
 129         <listitem><para>Specify names for the file descriptors passed. This is equivalent to setting
 130         <varname>FileDescriptorName=</varname> in socket unit files, and enables use of
 131         <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 132         Multiple entries may be specifies using separate options or by separating names with colons
 133         (<literal>:</literal>) in one option. In case more names are given than descriptors, superfluous ones will be
 134         ignored. In case less names are given than descriptors, the remaining file descriptors will be unnamed.
 135         </para></listitem>
 136       </varlistentry>
 137
 138       <xi:include href="standard-options.xml" xpointer="help" />
 139       <xi:include href="standard-options.xml" xpointer="version" />
 140     </variablelist>
 141   </refsect1>
 142
 143   <refsect1>
 144     <title>Environment variables</title>
 145     <variablelist class='environment-variables'>
 146       <varlistentry>
 147         <term><varname>$LISTEN_FDS</varname></term>
 148         <term><varname>$LISTEN_PID</varname></term>
 149         <term><varname>$LISTEN_FDNAMES</varname></term>
 150
 151         <listitem><para>See
 152         <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
 153       </varlistentry>
 154
 155       <varlistentry>
 156         <term><varname>$SYSTEMD_LOG_TARGET</varname></term>
 157         <term><varname>$SYSTEMD_LOG_LEVEL</varname></term>
 158         <term><varname>$SYSTEMD_LOG_COLOR</varname></term>
 159         <term><varname>$SYSTEMD_LOG_LOCATION</varname></term>
 160
 161         <listitem><para>Same as in
 162         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para></listitem>
 163       </varlistentry>
 164     </variablelist>
 165   </refsect1>
 166
 167   <refsect1>
 168     <title>Examples</title>
 169
 170     <example>
 171       <title>Run an echo server on port 2000</title>
 172
 173       <programlisting>$ systemd-socket-activate -l 2000 --inetd -a cat</programlisting>
 174     </example>
 175
 176     <example>
 177       <title>Run a socket-activated instance of <citerefentry><refentrytitle>systemd-journal-gatewayd</refentrytitle><manvolnum>8</manvolnum></citerefentry></title>
 178
 179       <programlisting>$ systemd-socket-activate -l 19531 /usr/lib/systemd/systemd-journal-gatewayd</programlisting>
 180     </example>
 181   </refsect1>
 182
 183   <refsect1>
 184     <title>See Also</title>
 185     <para>
 186       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 187       <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 188       <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 189       <citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 190       <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 191       <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 192       <citerefentry project='man-pages'><refentrytitle>cat</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 193     </para>
 194   </refsect1>
 195 </refentry>