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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 <systemd/sd-event.h></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> |