<?xml version='1.0'?> <!--*-nxml-*-->
-<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
- "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
-
-<!--
- This file is part of systemd.
-
- Copyright 2010 Lennart Poettering
-
- systemd is free software; you can redistribute it and/or modify it
- under the terms of the GNU Lesser General Public License as published by
- the Free Software Foundation; either version 2.1 of the License, or
- (at your option) any later version.
-
- systemd is distributed in the hope that it will be useful, but
- WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- Lesser General Public License for more details.
-
- You should have received a copy of the GNU Lesser General Public License
- along with systemd; If not, see <http://www.gnu.org/licenses/>.
--->
-
-<refentry id="systemd-notify">
-
- <refentryinfo>
- <title>systemd-notify</title>
- <productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
- </refentryinfo>
-
- <refmeta>
- <refentrytitle>systemd-notify</refentrytitle>
- <manvolnum>1</manvolnum>
- </refmeta>
-
- <refnamediv>
- <refname>systemd-notify</refname>
- <refpurpose>Notify service manager about start-up completion and other daemon status changes</refpurpose>
- </refnamediv>
-
- <refsynopsisdiv>
- <cmdsynopsis>
- <command>systemd-notify <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt" rep="repeat">VARIABLE=VALUE</arg></command>
- </cmdsynopsis>
- </refsynopsisdiv>
-
- <refsect1>
- <title>Description</title>
-
- <para><command>systemd-notify</command> may be
- called by daemon scripts to notify the init system
- about status changes. It can be used to send arbitrary
- information, encoded in an environment-block-like list
- of strings. Most importantly it can be used for
- start-up completion notification.</para>
-
- <para>This is mostly just a wrapper around
- <function>sd_notify()</function> and makes this
- functionality available to shell scripts. For details
- see
- <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
-
- <para>The command line may carry a list of
- environment variables to send as part of the status
- update.</para>
-
- <para>Note that systemd will refuse reception of
- status updates from this command unless
- <varname>NotifyAccess=all</varname> is set for the
- service unit this command is called from.</para>
-
- </refsect1>
-
- <refsect1>
- <title>Options</title>
-
- <para>The following options are understood:</para>
-
- <variablelist>
- <varlistentry>
- <term><option>-h</option></term>
- <term><option>--help</option></term>
-
- <listitem><para>Prints a short help
- text and exits.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--version</option></term>
-
- <listitem><para>Prints a short version
- string and exits.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--ready</option></term>
-
- <listitem><para>Inform the init system
- about service start-up
- completion. This is equivalent to
- <command>systemd-notify
- READY=1</command>. For details about
- the semantics of this option see
- <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--pid=</option></term>
-
- <listitem><para>Inform the init system
- about the main PID of the
- daemon. Takes a PID as argument. If
- the argument is omitted, the PID of the
- process that invoked
- <command>systemd-notify</command> is
- used. This is equivalent to
- <command>systemd-notify
- MAINPID=$PID</command>. For details
- about the semantics of this option see
- <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--status=</option></term>
-
- <listitem><para>Send a free-form
- status string for the daemon to the
- init systemd. This option takes the
- status string as argument. This is
- equivalent to <command>systemd-notify
- STATUS=...</command>. For details
- about the semantics of this option see
- <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--booted</option></term>
-
- <listitem><para>Returns 0 if the
- system was booted up with systemd,
- non-zero otherwise. If this option is
- passed, no message is sent. This option
- is hence unrelated to the other
- options. For details about the
- semantics of this option, see
- <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
-
- <varlistentry>
- <term><option>--readahead=</option></term>
-
- <listitem><para>Controls disk
- read-ahead operations. The argument
- must be a string, and either "cancel",
- "done" or "noreplay". For details
- about the semantics of this option see
- <citerefentry><refentrytitle>sd_readahead</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
- </varlistentry>
- </variablelist>
-
- </refsect1>
-
- <refsect1>
- <title>Exit status</title>
-
- <para>On success, 0 is returned, a non-zero failure
- code otherwise.</para>
- </refsect1>
-
- <refsect1>
- <title>Example</title>
-
- <example>
- <title>Start-up Notification and Status Updates</title>
-
- <para>A simple shell daemon that sends
- start-up notifications after having set up its
- communication channel. During runtime it sends
- further status updates to the init
- system:</para>
-
- <programlisting>#!/bin/bash
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+<!-- SPDX-License-Identifier: LGPL-2.1+ -->
+
+<refentry id="systemd-notify"
+ xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>systemd-notify</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>systemd-notify</refentrytitle>
+ <manvolnum>1</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>systemd-notify</refname>
+ <refpurpose>Notify service manager about start-up completion and other daemon status changes</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <cmdsynopsis>
+ <command>systemd-notify <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="opt" rep="repeat">VARIABLE=VALUE</arg></command>
+ </cmdsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><command>systemd-notify</command> may be called by daemon
+ scripts to notify the init system about status changes. It can be
+ used to send arbitrary information, encoded in an
+ environment-block-like list of strings. Most importantly, it can be
+ used for start-up completion notification.</para>
+
+ <para>This is mostly just a wrapper around
+ <function>sd_notify()</function> and makes this functionality
+ available to shell scripts. For details see
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+ </para>
+
+ <para>The command line may carry a list of environment variables
+ to send as part of the status update.</para>
+
+ <para>Note that systemd will refuse reception of status updates from this command unless
+ <varname>NotifyAccess=</varname> is set for the service unit this command is called from.</para>
+
+ <para>Note that <function>sd_notify()</function> notifications may be attributed to units correctly only if either
+ the sending process is still around at the time PID 1 processes the message, or if the sending process is
+ explicitly runtime-tracked by the service manager. The latter is the case if the service manager originally forked
+ off the process, i.e. on all processes that match <varname>NotifyAccess=</varname><option>main</option> or
+ <varname>NotifyAccess=</varname><option>exec</option>. Conversely, if an auxiliary process of the unit sends an
+ <function>sd_notify()</function> message and immediately exits, the service manager might not be able to properly
+ attribute the message to the unit, and thus will ignore it, even if
+ <varname>NotifyAccess=</varname><option>all</option> is set for it.</para>
+
+ <para><command>systemd-notify</command> will first attempt to invoke <function>sd_notify()</function> pretending to
+ have the PID of the invoking process. This will only succeed when invoked with sufficient privileges. On failure,
+ it will then fall back to invoking it under its own PID. This behaviour is useful in order that when the tool is
+ invoked from a shell script the shell process — and not the <command>systemd-notify</command> process — appears as
+ sender of the message, which in turn is helpful if the shell process is the main process of a service, due to the
+ limitations of <varname>NotifyAccess=</varname><option>all</option> described above.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Options</title>
+
+ <para>The following options are understood:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><option>--ready</option></term>
+
+ <listitem><para>Inform the init system about service start-up
+ completion. This is equivalent to <command>systemd-notify
+ READY=1</command>. For details about the semantics of this
+ option see
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--pid=</option></term>
+
+ <listitem><para>Inform the init system about the main PID of
+ the daemon. Takes a PID as argument. If the argument is
+ omitted, the PID of the process that invoked
+ <command>systemd-notify</command> is used. This is equivalent
+ to <command>systemd-notify MAINPID=$PID</command>. For details
+ about the semantics of this option see
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--uid=</option><replaceable>USER</replaceable></term>
+
+ <listitem><para>Set the user ID to send the notification from. Takes a UNIX user name or numeric UID. When
+ specified the notification message will be sent with the specified UID as sender, in place of the user the
+ command was invoked as. This option requires sufficient privileges in order to be able manipulate the user
+ identity of the process.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--status=</option></term>
+
+ <listitem><para>Send a free-form status string for the daemon
+ to the init systemd. This option takes the status string as
+ argument. This is equivalent to <command>systemd-notify
+ STATUS=…</command>. For details about the semantics of this
+ option see
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><option>--booted</option></term>
+
+ <listitem><para>Returns 0 if the system was booted up with
+ systemd, non-zero otherwise. If this option is passed, no
+ message is sent. This option is hence unrelated to the other
+ options. For details about the semantics of this option, see
+ <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>. An
+ alternate way to check for this state is to call
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ with the <command>is-system-running</command> command. It will
+ return <literal>offline</literal> if the system was not booted
+ with systemd. </para></listitem>
+ </varlistentry>
+
+ <xi:include href="standard-options.xml" xpointer="help" />
+ <xi:include href="standard-options.xml" xpointer="version" />
+ </variablelist>
+
+ </refsect1>
+
+ <refsect1>
+ <title>Exit status</title>
+
+ <para>On success, 0 is returned, a non-zero failure code
+ otherwise.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Example</title>
+
+ <example>
+ <title>Start-up Notification and Status Updates</title>
+
+ <para>A simple shell daemon that sends start-up notifications
+ after having set up its communication channel. During runtime it
+ sends further status updates to the init system:</para>
+
+ <programlisting>#!/bin/bash
mkfifo /tmp/waldo
-systemd-notify --ready --status="Waiting for data..."
+systemd-notify --ready --status="Waiting for data…"
while : ; do
read a < /tmp/waldo
systemd-notify --status="Processing $a"
- # Do something with $a ...
+ # Do something with $a …
- systemd-notify --status="Waiting for data..."
+ systemd-notify --status="Waiting for data…"
done</programlisting>
- </example>
- </refsect1>
-
- <refsect1>
- <title>See Also</title>
- <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- </para>
- </refsect1>
+ </example>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd.unit</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_booted</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
</refentry>
projects / thirdparty / systemd.git / blobdiff