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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/4.5/docbookx.dtd">
<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
<refentry id="sd_bus_get_current_handler" xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_bus_get_current_handler</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>sd_bus_get_current_handler</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_bus_get_current_handler</refname>
<refname>sd_bus_get_current_message</refname>
<refname>sd_bus_get_current_slot</refname>
<refname>sd_bus_get_current_userdata</refname>
<refpurpose>Query information of the callback a bus object is currently running</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>
<xi:include href="sd_bus_add_match.xml" xpointer="sd_bus_message_handler_t"/>
<funcprototype>
<funcdef>sd_bus_message_handler_t <function>sd_bus_get_current_handler</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>sd_bus_message* <function>sd_bus_get_current_message</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>sd_bus_slot* <function>sd_bus_get_current_slot</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>void* <function>sd_bus_get_current_userdata</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>Whenever sd-bus is about to invoke a user-supplied callback function, it stores the
current callback, D-Bus message, slot and userdata pointer and allows these to be queried via
<function>sd_bus_get_current_handler()</function>,
<function>sd_bus_get_current_message()</function>,
<function>sd_bus_get_current_slot()</function> and
<function>sd_bus_get_current_userdata()</function>, respectively. If <parameter>bus</parameter>
cannot be resolved or if execution does not reside in a user-supplied callback of
<parameter>bus</parameter>, these functions return <constant>NULL</constant>.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para>On success, these functions return the requested object. On failure, they return
<constant>NULL</constant>.</para>
</refsect1>
<xi:include href="libsystemd-pkgconfig.xml" />
<refsect1>
<title>History</title>
<para><function>sd_bus_get_current_handler()</function>,
<function>sd_bus_get_current_message()</function>,
<function>sd_bus_get_current_slot()</function>, and
<function>sd_bus_get_current_userdata()</function> were added in version 221.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para><simplelist type="inline">
<member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
<member><citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
</simplelist></para>
</refsect1>
</refentry>
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