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">
6 This file is part of systemd.
8 Copyright 2010 Lennart Poettering
10 systemd is free software; you can redistribute it and/or modify it
11 under the terms of the GNU Lesser General Public License as published by
12 the Free Software Foundation; either version 2.1 of the License, or
13 (at your option) any later version.
15 systemd is distributed in the hope that it will be useful, but
16 WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
20 You should have received a copy of the GNU Lesser General Public License
21 along with systemd; If not, see <http://www.gnu.org/licenses/>.
24 <refentry id="systemd-notify">
27 <title>systemd-notify</title>
28 <productname>systemd</productname>
32 <contrib>Developer</contrib>
33 <firstname>Lennart</firstname>
34 <surname>Poettering</surname>
35 <email>lennart@poettering.net</email>
41 <refentrytitle>systemd-notify</refentrytitle>
42 <manvolnum>1</manvolnum>
46 <refname>systemd-notify</refname>
47 <refpurpose>Notify service manager about start-up completion and other daemon status changes</refpurpose>
52 <command>systemd-notify <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt" rep="repeat">VARIABLE=VALUE</arg></command>
57 <title>Description</title>
59 <para><command>systemd-notify</command> may be
60 called by daemon scripts to notify the init system
61 about status changes. It can be used to send arbitrary
62 information, encoded in an environment-block-like list
63 of strings. Most importantly it can be used for
64 start-up completion notification.</para>
66 <para>This is mostly just a wrapper around
67 <function>sd_notify()</function> and makes this
68 functionality available to shell scripts. For details
70 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
72 <para>The command line may carry a list of
73 environment variables to send as part of the status
76 <para>Note that systemd will refuse reception of
77 status updates from this command unless
78 <varname>NotifyAccess=all</varname> is set for the
79 service unit this command is called from.</para>
84 <title>Options</title>
86 <para>The following options are understood:</para>
90 <term><option>-h</option></term>
91 <term><option>--help</option></term>
93 <listitem><para>Prints a short help
94 text and exits.</para></listitem>
98 <term><option>--version</option></term>
100 <listitem><para>Prints a short version
101 string and exits.</para></listitem>
105 <term><option>--ready</option></term>
107 <listitem><para>Inform the init system
108 about service start-up
109 completion. This is equivalent to
110 <command>systemd-notify
111 READY=1</command>. For details about
112 the semantics of this option see
113 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
117 <term><option>--pid=</option></term>
119 <listitem><para>Inform the init system
120 about the main PID of the
121 daemon. Takes a PID as argument. If
122 the argument is omitted the PID of the
124 <command>systemd-notify</command> is
125 used. This is equivalent to
126 <command>systemd-notify
127 MAINPID=$PID</command>. For details
128 about the semantics of this option see
129 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
133 <term><option>--status=</option></term>
135 <listitem><para>Send a free-form
136 status string for the daemon to the
137 init systemd. This option takes the
138 status string as argument. This is
139 equivalent to <command>systemd-notify
140 STATUS=...</command>. For details
141 about the semantics of this option see
142 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
146 <term><option>--booted</option></term>
148 <listitem><para>Returns 0 if the
149 system was booted up with systemd,
150 non-zero otherwise. If this option is
151 passed no message is sent. This option
152 is hence unrelated to the other
153 options. For details about the
154 semantics of this option see
155 <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
159 <term><option>--readahead=</option></term>
161 <listitem><para>Controls disk
162 read-ahead operations. The argument
163 must be a string, and either "cancel",
164 "done" or "noreplay". For details
165 about the semantics of this option see
166 <citerefentry><refentrytitle>sd_readahead</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
173 <title>Exit status</title>
175 <para>On success 0 is returned, a non-zero failure
176 code otherwise.</para>
180 <title>Example</title>
183 <title>Start-up Notification and Status Updates</title>
185 <para>A simple shell daemon that sends
186 start-up notifications after having set up its
187 communication channel. During runtime it sends
188 further status updates to the init
191 <programlisting>#!/bin/bash
194 systemd-notify --ready --status="Waiting for data..."
197 read a < /tmp/waldo
198 systemd-notify --status="Processing $a"
200 # Do something with $a ...
202 systemd-notify --status="Waiting for data..."
203 done</programlisting>
208 <title>See Also</title>
210 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
211 <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
212 <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
213 <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
214 <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>