-<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
-<!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 2015 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/>.
--->
+<?xml version='1.0'?>
+<!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="sd_event_exit" xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_event_exit</title>
<productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
</refentryinfo>
<refmeta>
conflict with regular exit codes returned by
<function>sd_event_loop()</function>, if these exit codes shall be
distinguishable.</para>
+
+ <para>Note that for most event source types passing the callback pointer as <constant>NULL</constant> in
+ the respective constructor call (i.e. in
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ …) has the effect of <function>sd_event_exit()</function> being invoked once the event source triggers,
+ with the specified userdata pointer cast to an integer as the exit code parameter. This is useful to
+ automatically terminate an event loop after some condition, such as a time-out or reception of
+ <constant>SIGTERM</constant> or similar. See the documentation for the respective constructor call for
+ details.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
- <para>On success, <function>sd_event_exit()</function> and
- <function>sd_event_get_exit_code()</function> return 0 or a positive
- integer. On failure, they return a negative errno-style error
- code.</para>
- </refsect1>
+ <para>On success, <function>sd_event_exit()</function> and <function>sd_event_get_exit_code()</function>
+ return 0 or a positive integer. On failure, they return a negative errno-style error code.</para>
- <refsect1>
- <title>Errors</title>
+ <refsect2>
+ <title>Errors</title>
- <para>Returned errors may indicate the following problems:</para>
+
<para>Returned errors may indicate the following problems:</para>
- <variablelist>
+ <variablelist>
- <varlistentry>
- <term><constant>-EINVAL</constant></term>
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
- <listitem><para>The event loop object or error code pointer are invalid.</para></listitem>
+
<listitem><para>The event loop object or error code pointer are invalid.</para></listitem>
- </varlistentry>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ECHILD</constant></term>
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
- <listitem><para>The event loop was created in a different process.</para></listitem>
- </varlistentry>
+
<listitem><para>The event loop was created in a different process.</para></listitem>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ESTALE</constant></term>
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
- <listitem><para>The event loop has exited already and all exit handlers are already processed.</para></listitem>
- </varlistentry>
+ <listitem><para>The event loop has exited already and all exit handlers are already processed.
+ </para></listitem>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ENODATA</constant></term>
+ <varlistentry>
+ <term><constant>-ENODATA</constant></term>
- <listitem><para>The event loop has not been requested to exit yet.</para></listitem>
- </varlistentry>
+
<listitem><para>The event loop has not been requested to exit yet.</para></listitem>
+ </varlistentry>
- </variablelist>
+ </variablelist>
+ </refsect2>
</refsect1>
<xi:include href="libsystemd-pkgconfig.xml" />
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_inotify</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>
projects / thirdparty / systemd.git / blobdiff