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diff --git a/man/sd_event_source_unref.xml b/man/sd_event_source_unref.xml new file mode 100644 index 0000000..a7699e3 --- /dev/null +++ b/man/sd_event_source_unref.xml @@ -0,0 +1,136 @@ +<?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 <systemd/sd-event.h></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 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 it is removed from its 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 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> |