man/systemd-socket-activate.xml

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  10   Copyright 2013 Zbigniew Jędrzejewski-Szmek
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  25
  26 <refentry id="systemd-socket-activate"
  27           xmlns:xi="http://www.w3.org/2001/XInclude">
  28
  29   <refentryinfo>
  30     <title>systemd-socket-activate</title>
  31     <productname>systemd</productname>
  32
  33     <authorgroup>
  34       <author>
  35         <contrib>Developer</contrib>
  36         <firstname>Zbigniew</firstname>
  37         <surname>Jędrzejewski-Szmek</surname>
  38         <email>zbyszek@in.waw.pl</email>
  39       </author>
  40     </authorgroup>
  41   </refentryinfo>
  42
  43   <refmeta>
  44     <refentrytitle>systemd-socket-activate</refentrytitle>
  45     <manvolnum>1</manvolnum>
  46   </refmeta>
  47
  48   <refnamediv>
  49     <refname>systemd-socket-activate</refname>
  50     <refpurpose>Test socket activation of daemons</refpurpose>
  51   </refnamediv>
  52
  53   <refsynopsisdiv>
  54     <cmdsynopsis>
  55       <command>systemd-socket-activate</command>
  56       <arg choice="opt" rep="repeat">OPTIONS</arg>
  57       <arg choice="plain"><replaceable>daemon</replaceable></arg>
  58       <arg choice="opt" rep="repeat">OPTIONS</arg>
  59     </cmdsynopsis>
  60   </refsynopsisdiv>
  61
  62   <refsect1>
  63     <title>Description</title>
  64
  65     <para><command>systemd-socket-activate</command> may be used to launch a socket-activated service program from the
  66     command line for testing purposes. It may also be used to launch individual instances of the service program per
  67     connection.
  68     </para>
  69
  70     <para>The daemon to launch and its options should be specified
  71     after options intended for <command>systemd-socket-activate</command>.
  72     </para>
  73
  74     <para>If the <option>--inetd</option> option is given, the socket file descriptor will be used as the standard
  75     input and output of the launched process. Otherwise, standard input and output will be inherited, and sockets will
  76     be passed through file descriptors 3 and higher. Sockets passed through <varname>$LISTEN_FDS</varname> to
  77     <command>systemd-socket-activate</command> will be passed through to the daemon, in the original positions. Other sockets
  78     specified with <option>--listen=</option> will use consecutive descriptors.  By default,
  79     <command>systemd-socket-activate</command> listens on a stream socket, use <option>--datagram</option> and
  80     <option>--seqpacket</option> to listen on datagram or sequential packet sockets instead (see below).
  81     </para>
  82   </refsect1>
  83
  84   <refsect1>
  85     <title>Options</title>
  86     <variablelist>
  87       <varlistentry>
  88         <term><option>-l <replaceable>address</replaceable></option></term>
  89         <term><option>--listen=<replaceable>address</replaceable></option></term>
  90
  91         <listitem><para>Listen on this <replaceable>address</replaceable>.
  92         Takes a string like <literal>2000</literal> or
  93         <literal>127.0.0.1:2001</literal>.</para>
  94         </listitem>
  95       </varlistentry>
  96
  97       <varlistentry>
  98         <term><option>-a</option></term>
  99         <term><option>--accept</option></term>
 100
 101         <listitem><para>Launch an instance of the service program for each connection and pass the connection
 102         socket.</para></listitem>
 103       </varlistentry>
 104
 105       <varlistentry>
 106         <term><option>-d</option></term>
 107         <term><option>--datagram</option></term>
 108
 109         <listitem><para>Listen on a datagram socket (<constant>SOCK_DGRAM</constant>), instead of a stream socket
 110         (<constant>SOCK_STREAM</constant>). May not be combined with <option>--seqpacket</option>.</para></listitem>
 111       </varlistentry>
 112
 113       <varlistentry>
 114         <term><option>--seqpacket</option></term>
 115
 116         <listitem><para>Listen on a sequential packet socket (<constant>SOCK_SEQPACKET</constant>), instead of a stream
 117         socket (<constant>SOCK_STREAM</constant>). May not be combined with
 118         <option>--datagram</option>.</para></listitem>
 119       </varlistentry>
 120
 121       <varlistentry>
 122         <term><option>--inetd</option></term>
 123
 124         <listitem><para>Use the inetd protocol for passing file descriptors, i.e. as standard input and standard
 125         output, instead of the new-style protocol for passing file descriptors using <varname>$LISTEN_FDS</varname>
 126         (see above).</para></listitem>
 127       </varlistentry>
 128
 129       <varlistentry>
 130         <term><option>-E <replaceable>VAR</replaceable><optional>=<replaceable>VALUE</replaceable></optional></option></term>
 131         <term><option>--setenv=<replaceable>VAR</replaceable><optional>=<replaceable>VALUE</replaceable></optional></option></term>
 132
 133         <listitem><para>Add this variable to the environment of the
 134         launched process. If <replaceable>VAR</replaceable> is
 135         followed by <literal>=</literal>, assume that it is a
 136         variable–value pair. Otherwise, obtain the value from the
 137         environment of <command>systemd-socket-activate</command> itself.
 138         </para></listitem>
 139       </varlistentry>
 140
 141       <varlistentry>
 142         <term><option>--fdname=</option><replaceable>NAME</replaceable><optional>:<replaceable>NAME</replaceable>…</optional></term>
 143
 144         <listitem><para>Specify names for the file descriptors passed. This is equivalent to setting
 145         <varname>FileDescriptorName=</varname> in socket unit files, and enables use of
 146         <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
 147         Multiple entries may be specifies using separate options or by separating names with colons
 148         (<literal>:</literal>) in one option. In case more names are given than descriptors, superfluous ones will be
 149         ignored. In case less names are given than descriptors, the remaining file descriptors will be unnamed.
 150         </para></listitem>
 151       </varlistentry>
 152
 153       <xi:include href="standard-options.xml" xpointer="help" />
 154       <xi:include href="standard-options.xml" xpointer="version" />
 155     </variablelist>
 156   </refsect1>
 157
 158   <refsect1>
 159     <title>Environment variables</title>
 160     <variablelist class='environment-variables'>
 161       <varlistentry>
 162         <term><varname>$LISTEN_FDS</varname></term>
 163         <term><varname>$LISTEN_PID</varname></term>
 164         <term><varname>$LISTEN_FDNAMES</varname></term>
 165
 166         <listitem><para>See
 167         <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
 168       </varlistentry>
 169
 170       <varlistentry>
 171         <term><varname>$SYSTEMD_LOG_TARGET</varname></term>
 172         <term><varname>$SYSTEMD_LOG_LEVEL</varname></term>
 173         <term><varname>$SYSTEMD_LOG_COLOR</varname></term>
 174         <term><varname>$SYSTEMD_LOG_LOCATION</varname></term>
 175
 176         <listitem><para>Same as in
 177         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>.</para></listitem>
 178       </varlistentry>
 179     </variablelist>
 180   </refsect1>
 181
 182   <refsect1>
 183     <title>Examples</title>
 184
 185     <example>
 186       <title>Run an echo server on port 2000</title>
 187
 188       <programlisting>$ systemd-socket-activate -l 2000 --inetd -a cat</programlisting>
 189     </example>
 190
 191     <example>
 192       <title>Run a socket-activated instance of <citerefentry><refentrytitle>systemd-journal-gatewayd</refentrytitle><manvolnum>8</manvolnum></citerefentry></title>
 193
 194       <programlisting>$ systemd-socket-activate -l 19531 /usr/lib/systemd/systemd-journal-gatewayd</programlisting>
 195     </example>
 196   </refsect1>
 197
 198   <refsect1>
 199     <title>See Also</title>
 200     <para>
 201       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 202       <citerefentry><refentrytitle>systemd.socket</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 203       <citerefentry><refentrytitle>systemd.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
 204       <citerefentry><refentrytitle>systemd-run</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
 205       <citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 206       <citerefentry><refentrytitle>sd_listen_fds_with_names</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 207       <citerefentry project='man-pages'><refentrytitle>cat</refentrytitle><manvolnum>1</manvolnum></citerefentry>
 208     </para>
 209   </refsect1>
 210 </refentry>