summaryrefslogtreecommitdiffstats
path: root/man/sd_event_exit.xml
diff options
context:
space:
mode:
Diffstat (limited to 'man/sd_event_exit.xml')
-rw-r--r--man/sd_event_exit.xml156
1 files changed, 156 insertions, 0 deletions
diff --git a/man/sd_event_exit.xml b/man/sd_event_exit.xml
new file mode 100644
index 0000000..bea8acd
--- /dev/null
+++ b/man/sd_event_exit.xml
@@ -0,0 +1,156 @@
+<?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-or-later -->
+
+<refentry id="sd_event_exit" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_exit</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_exit</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_exit</refname>
+ <refname>sd_event_get_exit_code</refname>
+
+ <refpurpose>Ask the event loop to exit</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include &lt;systemd/sd-event.h&gt;</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_exit</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>int <parameter>code</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_get_exit_code</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>int *<parameter>code</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_exit()</function> requests the event loop
+ specified in the <parameter>event</parameter> event loop object to
+ exit. The <parameter>code</parameter> parameter may be any integer
+ value and is returned as-is by
+ <citerefentry><refentrytitle>sd_event_loop</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ after the last event loop iteration. It may also be queried
+ using <function>sd_event_get_exit_code()</function>, see
+ below. </para>
+
+ <para>When exiting is requested the event loop will stop listening
+ for and dispatching regular event sources. Instead it will proceed
+ with executing only event sources registered with
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ in the order defined by their priority. After all exit event
+ sources have been dispatched the event loop is terminated.</para>
+
+ <para>If <function>sd_event_exit()</function> is invoked a second
+ time while the event loop is still processing exit event sources,
+ the exit code stored in the event loop object is updated, but
+ otherwise no further operation is executed.</para>
+
+ <para><function>sd_event_get_exit_code()</function> may be used to
+ query the exit code passed into
+ <function>sd_event_exit()</function> earlier.</para>
+
+ <para>While the full positive and negative integer ranges may be used
+ for the exit code, care should be taken not pick exit codes that
+ 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>
+
+ <refsect2>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>The event loop object or error code pointer are invalid.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop was created in a different process, library or module instance.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop has exited already and all exit handlers are already processed.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENODATA</constant></term>
+
+ <listitem><para>The event loop has not been requested to exit yet.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect2>
+ </refsect1>
+
+ <xi:include href="libsystemd-pkgconfig.xml" />
+
+ <refsect1>
+ <title>History</title>
+ <para><function>sd_event_exit()</function> and
+ <function>sd_event_get_exit_code()</function> were added in version 229.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_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>
+
+</refentry>