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543 lines
26 KiB
XML
543 lines
26 KiB
XML
<?xml version='1.0'?> <!--*-nxml-*-->
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<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
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"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!-- SPDX-License-Identifier: LGPL-2.1+ -->
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<refentry id="sd_bus_add_object"
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xmlns:xi="http://www.w3.org/2001/XInclude">
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<refentryinfo>
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<title>sd_bus_add_object</title>
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<productname>systemd</productname>
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</refentryinfo>
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<refmeta>
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<refentrytitle>sd_bus_add_object</refentrytitle>
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<manvolnum>3</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>sd_bus_add_object</refname>
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<refname>sd_bus_add_fallback</refname>
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<refname>sd_bus_add_object_vtable</refname>
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<refname>sd_bus_add_fallback_vtable</refname>
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<refname>SD_BUS_VTABLE_START</refname>
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<refname>SD_BUS_VTABLE_END</refname>
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<refname>SD_BUS_METHOD_WITH_NAMES_OFFSET</refname>
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<refname>SD_BUS_METHOD_WITH_NAMES</refname>
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<refname>SD_BUS_METHOD_WITH_OFFSET</refname>
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<refname>SD_BUS_METHOD</refname>
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<refname>SD_BUS_SIGNAL_WITH_NAMES</refname>
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<refname>SD_BUS_SIGNAL</refname>
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<refname>SD_BUS_WRITABLE_PROPERTY</refname>
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<refname>SD_BUS_PROPERTY</refname>
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<refname>SD_BUS_PARAM</refname>
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<refpurpose>Declare properties and methods for a D-Bus path</refpurpose>
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</refnamediv>
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<refsynopsisdiv>
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<funcsynopsis>
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<funcsynopsisinfo>#include <systemd/sd-bus-vtable.h></funcsynopsisinfo>
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<funcprototype>
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<funcdef>typedef int (*<function>sd_bus_message_handler_t</function>)</funcdef>
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<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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<paramdef>sd_bus_error *<parameter>ret_error</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>typedef int (*<function>sd_bus_property_get_t</function>)</funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>const char *<parameter>interface</parameter></paramdef>
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<paramdef>const char *<parameter>property</parameter></paramdef>
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<paramdef>sd_bus_message *<parameter>reply</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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<paramdef>sd_bus_error *<parameter>ret_error</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>typedef int (*<function>sd_bus_property_set_t</function>)</funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>const char *<parameter>interface</parameter></paramdef>
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<paramdef>const char *<parameter>property</parameter></paramdef>
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<paramdef>sd_bus_message *<parameter>value</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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<paramdef>sd_bus_error *<parameter>ret_error</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>typedef int (*<function>sd_bus_object_find_t</function>)</funcdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>const char *<parameter>interface</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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<paramdef>void **<parameter>ret_found</parameter></paramdef>
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<paramdef>sd_bus_error *<parameter>ret_error</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>int <function>sd_bus_add_object</function></funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>sd_bus_slot **<parameter>slot</parameter></paramdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>sd_bus_message_handler_t <parameter>callback</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>int <function>sd_bus_add_fallback</function></funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>sd_bus_slot **<parameter>slot</parameter></paramdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>sd_bus_message_handler_t <parameter>callback</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>int <function>sd_bus_add_object_vtable</function></funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>sd_bus_slot **<parameter>slot</parameter></paramdef>
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<paramdef>const char *<parameter>path</parameter></paramdef>
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<paramdef>const char *<parameter>interface</parameter></paramdef>
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<paramdef>const sd_bus_vtable *<parameter>vtable</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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</funcprototype>
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<funcprototype>
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<funcdef>int <function>sd_bus_add_fallback_vtable</function></funcdef>
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<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
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<paramdef>sd_bus_slot **<parameter>slot</parameter></paramdef>
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<paramdef>const char *<parameter>prefix</parameter></paramdef>
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<paramdef>const char *<parameter>interface</parameter></paramdef>
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<paramdef>const sd_bus_vtable *<parameter>vtable</parameter></paramdef>
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<paramdef>sd_bus_object_find_t <parameter>find</parameter></paramdef>
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<paramdef>void *<parameter>userdata</parameter></paramdef>
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</funcprototype>
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<para>
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<constant>SD_BUS_VTABLE_START(<replaceable>flags</replaceable>)</constant>
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</para>
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<para>
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<constant>SD_BUS_VTABLE_END</constant>
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</para>
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<para>
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<constant>SD_BUS_METHOD_WITH_NAMES_OFFSET(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>in_names</replaceable>,
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<replaceable>result</replaceable>,
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<replaceable>out_names</replaceable>,
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<replaceable>handler</replaceable>,
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<replaceable>offset</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_METHOD_WITH_NAMES(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>in_names</replaceable>,
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<replaceable>result</replaceable>,
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<replaceable>out_names</replaceable>,
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<replaceable>handler</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_METHOD_WITH_OFFSET(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>result</replaceable>,
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<replaceable>handler</replaceable>,
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<replaceable>offset</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_METHOD(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>result</replaceable>,
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<replaceable>handler</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_SIGNAL_WITH_NAMES(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>names</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_SIGNAL(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_WRITABLE_PROPERTY(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>get</replaceable>,
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<replaceable>set</replaceable>,
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<replaceable>offset</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_PROPERTY(
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<replaceable>member</replaceable>,
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<replaceable>signature</replaceable>,
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<replaceable>get</replaceable>,
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<replaceable>offset</replaceable>,
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<replaceable>flags</replaceable>)
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</constant>
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</para>
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<para>
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<constant>SD_BUS_PARAM(<replaceable>name</replaceable>)</constant>
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</para>
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</funcsynopsis>
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</refsynopsisdiv>
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<refsect1>
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<title>Description</title>
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<para><function>sd_bus_add_object_vtable()</function> is used to declare attributes for the
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object path <parameter>path</parameter> connected to the bus connection
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<parameter>bus</parameter> under the interface <parameter>interface</parameter>. The table
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<parameter>vtable</parameter> may contain property declarations using
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<constant>SD_BUS_PROPERTY()</constant> or <constant>SD_BUS_WRITABLE_PROPERTY()</constant>,
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method declarations using <constant>SD_BUS_METHOD()</constant>,
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<constant>SD_BUS_METHOD_WITH_NAMES()</constant>,
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<constant>SD_BUS_METHOD_WITH_OFFSET()</constant>, or
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<constant>SD_BUS_METHOD_WITH_NAMES_OFFSET()</constant>, and signal declarations using
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<constant>SD_BUS_SIGNAL_WITH_NAMES()</constant> or <constant>SD_BUS_SIGNAL()</constant>, see
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below. The <replaceable>userdata</replaceable> parameter contains a pointer that will be passed
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to various callback functions. It may be specified as <constant>NULL</constant> if no value is
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necessary. An interface can have any number of vtables attached to it.</para>
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<para><function>sd_bus_add_fallback_vtable()</function> is similar to
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<function>sd_bus_add_object_vtable()</function>, but is used to register "fallback" attributes.
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When looking for an attribute declaration, bus object paths registered with
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<function>sd_bus_add_object_vtable()</function> are checked first. If no match is found, the
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fallback vtables are checked for each prefix of the bus object path, i.e. with the last
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slash-separated components successively removed. This allows the vtable to be used for an
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arbitrary number of dynamically created objects.</para>
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<para>Parameter <replaceable>find</replaceable> is a function which is used to locate the target
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object based on the bus object path <replaceable>path</replaceable>. It must return
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<constant>1</constant> and set the <parameter>ret_found</parameter> output parameter if the
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object is found, return <constant>0</constant> if the object was not found, and return a
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negative errno-style error code or initialize the error structure
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<replaceable>ret_error</replaceable> on error. The pointer passed in
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<parameter>ret_found</parameter> will be used as the <parameter>userdata</parameter> parameter
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for the callback functions (offset by the <parameter>offset</parameter> offsets as specified in
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the vtable entries).</para>
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<para><function>sd_bus_add_object()</function> attaches a callback directly to the object path
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<parameter>path</parameter>. An object path can have any number of callbacks attached to it.
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Each callback is prepended to the list of callbacks which are always called in order.
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<function>sd_bus_add_fallback()</function> is similar to
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<function>sd_bus_add_object()</function> but applies to fallback paths instead.</para>
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<para>When a request is received, any associated callbacks are called sequentially until a
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callback returns a non-zero integer. Return zero from a callback to give other callbacks the
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chance to process the request. Callbacks are called in the following order: first, callbacks
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attached directly to the request object path are called, followed by any D-Bus method callbacks
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attached to the request object path, interface and member. Finally, the property callbacks
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attached to the request object path, interface and member are called. If the final callback
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returns zero, an error reply is sent back to the caller indicating no matching object for the
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request was found. Note that you can return a positive integer from a callback without
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immediately sending a reply. This informs sd-bus this callback will take responsibility for
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replying to the request without forcing the callback to produce a reply immediately. This allows
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a callback to perform any number of asynchronous operations required to construct a reply. Note
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that if producing a reply takes too long, the method call will time out at the caller.</para>
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<para>If a callback was invoked to handle a request that expects a reply and the callback
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returns a negative value, the value is interpreted as a negative errno-style error code and sent
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back to the caller as a D-Bus error as if
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<citerefentry><refentrytitle>sd_bus_reply_method_errno</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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was called. Additionally, all callbacks take a <structname>sd_bus_error</structname> output
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parameter that can be used to provide more detailed error information. If
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<parameter>ret_error</parameter> is set when the callback finishes, the corresponding D-Bus
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error is sent back to the caller as if
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<citerefentry><refentrytitle>sd_bus_reply_method_error</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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was called. Any error stored in <parameter>ret_error</parameter> takes priority over any
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negative values returned by the same callback when determining which error to send back to
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the caller. Use
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<citerefentry><refentrytitle>sd_bus_error_set</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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or one of its variants to set <parameter>ret_error</parameter> and return a negative integer
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from a callback with a single function call. To send an error reply after a callback has already
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finished, use
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<citerefentry><refentrytitle>sd_bus_reply_method_errno</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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or one of its variants.</para>
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<para>For all functions, a match slot is created internally. If the output parameter
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<replaceable>slot</replaceable> is <constant>NULL</constant>, a "floating" slot object is
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created, see
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<citerefentry><refentrytitle>sd_bus_slot_set_floating</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
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Otherwise, a pointer to the slot object is returned. In that case, the reference to the slot
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object should be dropped when the vtable is not needed anymore, see
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<citerefentry><refentrytitle>sd_bus_slot_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
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</para>
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<refsect2>
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<title>The <structname>sd_bus_vtable</structname> array</title>
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<para>The array consists of the structures of type <structname>sd_bus_vtable</structname>, but it
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should never be filled in manually, but through one of the following macros:</para>
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<variablelist>
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<varlistentry>
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<term><constant>SD_BUS_VTABLE_START()</constant></term>
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<term><constant>SD_BUS_VTABLE_END</constant></term>
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<listitem><para>Those must always be the first and last element.</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>SD_BUS_METHOD_WITH_NAMES_OFFSET()</constant></term>
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<term><constant>SD_BUS_METHOD_WITH_NAMES()</constant></term>
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<term><constant>SD_BUS_METHOD_WITH_OFFSET()</constant></term>
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<term><constant>SD_BUS_METHOD()</constant></term>
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<listitem><para>Declare a D-Bus method with the name <replaceable>member</replaceable>,
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parameter signature <replaceable>signature</replaceable>, result signature
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<replaceable>result</replaceable>. Parameters <replaceable>in_names</replaceable> and
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<replaceable>out_names</replaceable> specify the argument names of the input and output
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arguments in the function signature. The handler function
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<replaceable>handler</replaceable> must be of type
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<function>sd_bus_message_handler_t</function>. It will be called to handle the incoming
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messages that call this method. It receives a pointer that is the
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<replaceable>userdata</replaceable> parameter passed to the registration function offset
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by <replaceable>offset</replaceable> bytes. This may be used to pass pointers to different
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fields in the same data structure to different methods in the same vtable. To send a reply
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from <parameter>handler</parameter>, call
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<citerefentry><refentrytitle>sd_bus_reply_method_return</refentrytitle><manvolnum>3</manvolnum></citerefentry>
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with the message the callback was invoked with. <replaceable>in_names</replaceable> and
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<replaceable>out_names</replaceable> should be created using the
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<constant>SD_BUS_PARAM()</constant> macro, see below. Parameter
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<replaceable>flags</replaceable> is a combination of flags, see below.</para>
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<para><constant>SD_BUS_METHOD_WITH_NAMES()</constant>,
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<constant>SD_BUS_METHOD_WITH_OFFSET()</constant>, and <constant>SD_BUS_METHOD()</constant>
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are variants which specify zero offset (<replaceable>userdata</replaceable> parameter is
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passed with no change), leave the names unset (i.e. no parameter names), or both.</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>SD_BUS_SIGNAL_WITH_NAMES()</constant></term>
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<term><constant>SD_BUS_SIGNAL()</constant></term>
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<listitem><para>Declare a D-Bus signal with the name <replaceable>member</replaceable>,
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parameter signature <replaceable>signature</replaceable>, and argument names
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<replaceable>names</replaceable>. <replaceable>names</replaceable> should be
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created using the <constant>SD_BUS_PARAM()</constant> macro, see below.
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Parameter <replaceable>flags</replaceable> is a combination of flags, see below.
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</para>
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<para>Equivalent to <constant>SD_BUS_SIGNAL_WITH_NAMES()</constant> with the
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<replaceable>names</replaceable> parameter unset (i.e. no parameter names).</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>SD_BUS_WRITABLE_PROPERTY()</constant></term>
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<term><constant>SD_BUS_PROPERTY()</constant></term>
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<listitem><para>Declare a D-Bus property with the name <replaceable>member</replaceable>
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and value signature <replaceable>signature</replaceable>. Parameters
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<replaceable>get</replaceable> and <replaceable>set</replaceable> are the getter and
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setter methods. They are called with a pointer that is the
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<replaceable>userdata</replaceable> parameter passed to the registration function offset
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by <replaceable>offset</replaceable> bytes. This may be used pass pointers to different
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fields in the same data structure to different setters and getters in the same vtable.
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Parameter <replaceable>flags</replaceable> is a combination of flags, see below.</para>
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<para>The setter and getter methods may be omitted (specified as
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<constant>NULL</constant>), if the property is one of the basic types or
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<literal>as</literal> in case of read-only properties. In those cases, the
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<replaceable>userdata</replaceable> and <replaceable>offset</replaceable> parameters must
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together point to a valid variable of the corresponding type. A default setter and getter
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will be provided, which simply copy the argument between this variable and the message.
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</para>
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<para><constant>SD_BUS_PROPERTY()</constant> is used to define a read-only property.
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</para></listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>SD_BUS_PARAM()</constant></term>
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<listitem><para>Parameter names should be wrapped in this macro, see the example below.
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</para></listitem>
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</varlistentry>
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</variablelist>
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</refsect2>
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<refsect2>
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<title>Flags</title>
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<para>The <replaceable>flags</replaceable> parameter is used to specify a combination of
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<ulink url="https://dbus.freedesktop.org/doc/dbus-specification.html#introspection-format">D-Bus annotations</ulink>.
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</para>
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<variablelist>
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<varlistentry>
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<term><constant>SD_BUS_VTABLE_DEPRECATED</constant></term>
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<listitem><para>Mark this vtable entry as deprecated using the
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<constant>org.freedesktop.DBus.Deprecated</constant> annotation in introspection data. If
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specified for <constant>SD_BUS_VTABLE_START()</constant>, the annotation is applied to the
|
|
enclosing interface.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>SD_BUS_VTABLE_HIDDEN</constant></term>
|
|
|
|
<listitem><para>Make this vtable entry hidden. It will not be shown in introspection data.
|
|
If specified for <constant>SD_BUS_VTABLE_START()</constant>, all entries in the array are
|
|
hidden.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>SD_BUS_VTABLE_UNPRIVILEGED</constant></term>
|
|
|
|
<listitem><para>Mark this vtable entry as unprivileged. If not specified, the
|
|
<constant>org.freedesktop.systemd1.Privileged</constant> annotation with value
|
|
<literal>true</literal> will be shown in introspection data.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>SD_BUS_VTABLE_METHOD_NO_REPLY</constant></term>
|
|
|
|
<listitem><para>Mark his vtable entry as a method that will not return a reply using the
|
|
<constant>org.freedesktop.DBus.Method.NoReply</constant> annotation in introspection data.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>SD_BUS_VTABLE_PROPERTY_CONST</constant></term>
|
|
<term><constant>SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE</constant></term>
|
|
<term><constant>SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION</constant></term>
|
|
|
|
<listitem><para>Those three flags correspond to different values of the
|
|
<constant>org.freedesktop.DBus.Property.EmitsChangedSignal</constant> annotation, which
|
|
specifies whether the
|
|
<constant>org.freedesktop.DBus.Properties.PropertiesChanged</constant> signal is emitted
|
|
whenever the property changes. <constant>SD_BUS_VTABLE_PROPERTY_CONST</constant>
|
|
corresponds to <constant>const</constant> and means that the property never changes during
|
|
the lifetime of the object it belongs to, so no signal needs to be emitted.
|
|
<constant>SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE</constant> corresponds to
|
|
<constant>true</constant> and means that the signal is emitted.
|
|
<constant>SD_BUS_VTABLE_PROPERTY_EMITS_INVALIDATION</constant> corresponds to
|
|
<constant>invalidates</constant> and means that the signal is emitted, but the value is
|
|
not included in the signal.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>SD_BUS_VTABLE_PROPERTY_EXPLICIT</constant></term>
|
|
|
|
<listitem><para>Mark this vtable property entry as requiring explicit request to for the
|
|
value to be shown (generally because the value is large or slow to calculate). This entry
|
|
cannot be combined with <constant>SD_BUS_VTABLE_PROPERTY_EMITS_CHANGE</constant>, and will
|
|
not be shown in property listings by default (e.g. <command>busctl introspect</command>).
|
|
This corresponds to the <constant>org.freedesktop.systemd1.Explicit</constant> annotation
|
|
in introspection data.</para></listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect2>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Examples</title>
|
|
|
|
<example>
|
|
<title>Create a simple listener on the bus</title>
|
|
|
|
<programlisting><xi:include href="vtable-example.c" parse="text" /></programlisting>
|
|
|
|
<para>This creates a simple client on the bus (the user bus, when run as normal user). We may
|
|
use the D-Bus <constant>org.freedesktop.DBus.Introspectable.Introspect</constant> call to
|
|
acquire the XML description of the interface:</para>
|
|
|
|
<programlisting><xi:include href="vtable-example.xml" parse="text" /></programlisting>
|
|
</example>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Return Value</title>
|
|
|
|
<para>On success, <function>sd_bus_add_object_vtable</function> and
|
|
<function>sd_bus_add_fallback_vtable</function> calls 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>One of the required parameters is <constant>NULL</constant> or invalid. A
|
|
reserved D-Bus interface was passed as the <replaceable>interface</replaceable> parameter.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ENOPKG</constant></term>
|
|
|
|
<listitem><para>The bus cannot be resolved.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ECHILD</constant></term>
|
|
|
|
<listitem><para>The bus was created in a different process.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ENOMEM</constant></term>
|
|
|
|
<listitem><para>Memory allocation failed.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-EPROTOTYPE</constant></term>
|
|
|
|
<listitem><para><function>sd_bus_add_object_vtable</function> and
|
|
<function>sd_bus_add_fallback_vtable</function> have been both called for the same bus
|
|
object path, which is not allowed.</para></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-EEXIST</constant></term>
|
|
|
|
<listitem><para>This vtable has already been registered for this
|
|
<replaceable>interface</replaceable> and <replaceable>path</replaceable>.
|
|
</para></listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect2>
|
|
</refsect1>
|
|
|
|
<xi:include href="libsystemd-pkgconfig.xml" />
|
|
|
|
<refsect1>
|
|
<title>See Also</title>
|
|
|
|
<para>
|
|
<citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>busctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|