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+<?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_source_unref" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_unref</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_unref</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_unref</refname>
+ <refname>sd_event_source_unrefp</refname>
+ <refname>sd_event_source_ref</refname>
+ <refname>sd_event_source_disable_unref</refname>
+ <refname>sd_event_source_disable_unrefp</refname>
+
+ <refpurpose>Increase or decrease event source reference counters</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include &lt;systemd/sd-event.h&gt;</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>sd_event_source* <function>sd_event_source_unref</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>void <function>sd_event_source_unrefp</function></funcdef>
+ <paramdef>sd_event_source **<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>sd_event_source* <function>sd_event_source_ref</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>sd_event_source* <function>sd_event_source_disable_unref</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>void <function>sd_event_source_disable_unrefp</function></funcdef>
+ <paramdef>sd_event_source **<parameter>source</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_unref()</function> may be used to decrement by one the internal reference
+ counter of the event source object specified as <parameter>source</parameter>. The reference counter is
+ initially set to one, when the event source is created with calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry> or
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>. When
+ the reference counter reaches zero, the object is detached from the event loop object and destroyed.
+ </para>
+
+ <para><function>sd_event_source_unrefp()</function> is similar to
+ <function>sd_event_source_unref()</function> but takes a pointer to a
+ pointer to an <type>sd_event_source</type> object. This call is useful in
+ conjunction with GCC's and LLVM's <ulink
+ url="https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html">Clean-up
+ Variable Attribute</ulink>. Note that this function is defined as
+ inline function.</para>
+
+ <para><function>sd_event_source_ref()</function> may be used to increase by one the internal reference
+ counter of the event source object specified as <parameter>source</parameter>.</para>
+
+ <para><function>sd_event_source_unref()</function>,
+ <function>sd_bus_creds_unrefp()</function> and
+ <function>sd_bus_creds_ref()</function> execute no operation if
+ the passed event source object is
+ <constant>NULL</constant>.</para>
+
+ <para>Note that event source objects stay alive and may be dispatched as long as they have a reference
+ counter greater than zero. In order to drop a reference of an event source and make sure the associated
+ event source handler function is not called anymore it is recommended to combine a call of
+ <function>sd_event_source_unref()</function> with a prior call to
+ <function>sd_event_source_set_enabled()</function> with <constant>SD_EVENT_OFF</constant> or call
+ <function>sd_event_source_disable_unref()</function>, see below.</para>
+
+ <para><function>sd_event_source_disable_unref()</function> combines a call to
+ <function>sd_event_source_set_enabled()</function> with <constant>SD_EVENT_OFF</constant> with
+ <function>sd_event_source_unref()</function>. This ensures that the source is disabled before the local
+ reference to it is lost. The <parameter>source</parameter> parameter is allowed to be
+ <constant>NULL</constant>.</para>
+
+ <para><function>sd_event_source_disable_unrefp()</function> is similar to
+ <function>sd_event_source_unrefp()</function>, but in addition disables the source first. This call is
+ useful in conjunction with GCC's and LLVM's
+ <ulink url="https://gcc.gnu.org/onlinedocs/gcc/Common-Variable-Attributes.html">Clean-up Variable
+ Attribute</ulink>. Note that this function is defined as inline function.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para><function>sd_event_source_unref()</function> and
+ <function>sd_event_source_disable_unref()</function> always return <constant>NULL</constant>.
+ <function>sd_event_source_ref()</function> always returns the event source object passed in.</para>
+ </refsect1>
+
+ <xi:include href="libsystemd-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_io</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_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_inotify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>