1<?xml version='1.0'?> <!--*-nxml-*-->
2<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3  "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
4<!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
5
6<refentry id="sd_bus_add_object_manager"
7          xmlns:xi="http://www.w3.org/2001/XInclude">
8
9  <refentryinfo>
10    <title>sd_bus_add_object_manager</title>
11    <productname>systemd</productname>
12  </refentryinfo>
13
14  <refmeta>
15    <refentrytitle>sd_bus_add_object_manager</refentrytitle>
16    <manvolnum>3</manvolnum>
17  </refmeta>
18
19  <refnamediv>
20    <refname>sd_bus_add_object_manager</refname>
21
22    <refpurpose>Add a D-Bus object manager for a D-Bus object sub-tree</refpurpose>
23  </refnamediv>
24
25  <refsynopsisdiv>
26    <funcsynopsis>
27      <funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
28
29      <funcprototype>
30        <funcdef>int <function>sd_bus_add_object_manager</function></funcdef>
31        <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
32        <paramdef>sd_bus_slot **<parameter>slot</parameter></paramdef>
33        <paramdef>const char *<parameter>path</parameter></paramdef>
34      </funcprototype>
35    </funcsynopsis>
36  </refsynopsisdiv>
37
38  <refsect1>
39    <title>Description</title>
40
41    <para><function>sd_bus_add_object_manager()</function> installs a handler for the given path
42    that implements the <function>GetManagedObjects()</function> method of the
43    <constant>org.freedesktop.DBus.ObjectManager</constant> interface. See
44    <ulink url="https://dbus.freedesktop.org/doc/dbus-specification.html#standard-interfaces-objectmanager">
45    org.freedesktop.DBus.ObjectManager</ulink> for more information.</para>
46
47    <para>To implement the <function>InterfacesAdded</function> and
48    <function>InterfacesRemoved</function> signals of the
49    <constant>org.freedesktop.DBus.ObjectManager</constant> interface, call
50    <citerefentry><refentrytitle>sd_bus_emit_interfaces_added</refentrytitle><manvolnum>3</manvolnum></citerefentry> and
51    <citerefentry><refentrytitle>sd_bus_emit_interfaces_removed</refentrytitle><manvolnum>3</manvolnum></citerefentry>
52    whenever interfaces are added or removed from the sub-tree, respectively.</para>
53
54    <para>When <function>sd_bus_add_object_manager()</function> succeeds, a slot is created
55    internally. If the output parameter <replaceable>slot</replaceable> is <constant>NULL</constant>,
56    a "floating" slot object is created, see
57    <citerefentry><refentrytitle>sd_bus_slot_set_floating</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
58    Otherwise, a pointer to the slot object is returned. In that case, the reference to the slot
59    object should be dropped when the object manager is not needed anymore, see
60    <citerefentry><refentrytitle>sd_bus_slot_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
61    </para>
62  </refsect1>
63
64  <refsect1>
65    <title>Return Value</title>
66
67    <para>On success, <function>sd_bus_add_object_manager()</function> returns a non-negative
68    integer. On failure, it returns a negative errno-style error code.</para>
69
70    <refsect2>
71      <title>Errors</title>
72
73      <para>Returned errors may indicate the following problems:</para>
74
75      <variablelist>
76        <varlistentry>
77          <term><constant>-EINVAL</constant></term>
78
79          <listitem><para>One of the required parameters is <constant>NULL</constant> or
80          <parameter>path</parameter> is not a valid object path.
81          </para></listitem>
82        </varlistentry>
83
84        <varlistentry>
85          <term><constant>-ENOPKG</constant></term>
86
87          <listitem><para>The bus cannot be resolved.</para></listitem>
88        </varlistentry>
89
90        <varlistentry>
91          <term><constant>-ECHILD</constant></term>
92
93          <listitem><para>The bus was created in a different process.</para></listitem>
94        </varlistentry>
95
96        <varlistentry>
97          <term><constant>-ENOMEM</constant></term>
98
99          <listitem><para>Memory allocation failed.</para></listitem>
100        </varlistentry>
101      </variablelist>
102    </refsect2>
103  </refsect1>
104
105  <xi:include href="libsystemd-pkgconfig.xml" />
106
107  <refsect1>
108    <title>See Also</title>
109
110    <para>
111      <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
112      <citerefentry><refentrytitle>busctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
113      <citerefentry><refentrytitle>sd_bus_add_object_vtable</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
114      <citerefentry><refentrytitle>sd_bus_emit_interfaces_added</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
115      <citerefentry><refentrytitle>sd_bus_slot_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>
116    </para>
117  </refsect1>
118</refentry>
119