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diff --git a/man/sd_bus_emit_signal.xml b/man/sd_bus_emit_signal.xml new file mode 100644 index 0000000..08d5be4 --- /dev/null +++ b/man/sd_bus_emit_signal.xml @@ -0,0 +1,243 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!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_bus_emit_signal" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_emit_signal</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_emit_signal</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_emit_signal</refname> + <refname>sd_bus_emit_signalv</refname> + <refname>sd_bus_emit_interfaces_added</refname> + <refname>sd_bus_emit_interfaces_added_strv</refname> + <refname>sd_bus_emit_interfaces_removed</refname> + <refname>sd_bus_emit_interfaces_removed_strv</refname> + <refname>sd_bus_emit_properties_changed</refname> + <refname>sd_bus_emit_properties_changed_strv</refname> + <refname>sd_bus_emit_object_added</refname> + <refname>sd_bus_emit_object_removed</refname> + + <refpurpose>Convenience functions for emitting (standard) D-Bus signals</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus-vtable.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_signal</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>const char *<parameter>member</parameter></paramdef> + <paramdef>const char *<parameter>types</parameter></paramdef> + <paramdef>...</paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_signalv</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>const char *<parameter>member</parameter></paramdef> + <paramdef>const char *<parameter>types</parameter></paramdef> + <paramdef>va_list <parameter>ap</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_interfaces_added</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>...</paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_interfaces_added_strv</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char **<parameter>interfaces</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_interfaces_removed</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>...</paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_interfaces_removed_strv</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char **<parameter>interfaces</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_properties_changed</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>const char *<parameter>name</parameter></paramdef> + <paramdef>...</paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_properties_changed_strv</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + <paramdef>const char *<parameter>interface</parameter></paramdef> + <paramdef>const char **<parameter>names</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_object_added</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_emit_object_removed</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>const char *<parameter>path</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_bus_emit_signal()</function> is a convenience function for initializing a + bus message object and emitting the corresponding D-Bus signal. It combines the + <citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_message_append</refentrytitle><manvolnum>3</manvolnum></citerefentry> and + <citerefentry><refentrytitle>sd_bus_send</refentrytitle><manvolnum>3</manvolnum></citerefentry> + functions into a single function call. <function>sd_bus_emit_signalv()</function> is + equivalent to <function>sd_bus_message_append()</function>, except that it is called with a + <literal>va_list</literal> instead of a variable number of arguments.</para> + + <para><function>sd_bus_emit_interfaces_added()</function> and + <function>sd_bus_emit_interfaces_removed()</function> are used to implement the + <function>InterfacesAdded</function> and <function>InterfacesRemoved</function> signals of the + <constant>org.freedesktop.DBus.ObjectManager</constant> interface. They take a path whose + interfaces have been modified as an argument and a variable list of interfaces that have been + added or removed, respectively. The final argument passed to + <function>sd_bus_emit_interfaces_added()</function> and + <function>sd_bus_emit_interfaces_removed()</function> <emphasis>must</emphasis> be + <constant>NULL</constant>. This allows both functions to safely determine the number of passed + interface arguments. <function>sd_bus_emit_interfaces_added_strv()</function> and + <function>sd_bus_emit_interfaces_removed_strv()</function> are identical to their respective + counterparts but both take the list of interfaces as a single argument instead of a variable + number of arguments.</para> + + <para><function>sd_bus_emit_properties_changed()</function> is used to implement the + <function>PropertiesChanged</function> signal of the + <constant>org.freedesktop.DBus.Properties</constant> interface. It takes an object path, + interface and a variable list of property names as its arguments. The final argument passed to + <function>sd_bus_emit_properties_changed()</function> <emphasis>must</emphasis> be + <constant>NULL</constant>. This allows it to safely determine the number of passed property + names. <function>sd_bus_emit_properties_changed_strv()</function> is identical to + <function>sd_bus_emit_properties_changed()</function> but takes the list of property names as a + single argument instead of a variable number of arguments.</para> + + <para><function>sd_bus_emit_object_added()</function> and + <function>sd_bus_emit_object_removed()</function> are convenience functions for emitting the + <function>InterfacesAdded</function> or <function>InterfacesRemoved</function> signals for all + interfaces registered on a specific object path, respectively. This includes any parent fallback + vtables if they are not overridden by a more applicable child vtable. It also includes all the + standard D-Bus interfaces implemented by sd-bus itself on any registered object.</para> + + <para>Note that <function>sd_bus_emit_interfaces_added()</function>, + <function>sd_bus_emit_interfaces_removed()</function>, + <function>sd_bus_emit_object_added()</function> and + <function>sd_bus_emit_object_removed()</function> require an object manager to have been + registered on the given object path or one of its parent object paths using + <citerefentry><refentrytitle>sd_bus_add_object_manager</refentrytitle><manvolnum>3</manvolnum></citerefentry>. + </para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On success, these functions return a non-negative 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>-ESRCH</constant></term> + + <listitem><para>One of <function>sd_bus_emit_interfaces_added()</function>, + <function>sd_bus_emit_interfaces_removed()</function>, + <function>sd_bus_emit_object_added()</function> or + <function>sd_bus_emit_object_removed()</function> was called on an object without an + object manager registered on its own object path or one of its parent object paths. + </para></listitem> + </varlistentry> + </variablelist> + + <para>See the man pages of + <citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_message_append</refentrytitle><manvolnum>3</manvolnum></citerefentry> and + <citerefentry><refentrytitle>sd_bus_send</refentrytitle><manvolnum>3</manvolnum></citerefentry> + for more possible errors.</para> + </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>, + <citerefentry><refentrytitle>sd_bus_message_new_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_message_append</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_call_method</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> +</refentry> |