mirror of
https://github.com/systemd/systemd.git
synced 2024-11-23 02:03:37 +08:00
138 lines
5.4 KiB
XML
138 lines
5.4 KiB
XML
<?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_start"
|
|
xmlns:xi="http://www.w3.org/2001/XInclude">
|
|
|
|
<refentryinfo>
|
|
<title>sd_bus_start</title>
|
|
<productname>systemd</productname>
|
|
</refentryinfo>
|
|
|
|
<refmeta>
|
|
<refentrytitle>sd_bus_start</refentrytitle>
|
|
<manvolnum>3</manvolnum>
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>sd_bus_start</refname>
|
|
|
|
<refpurpose>Initiate a bus connection to the D-bus broker daemon
|
|
</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<funcsynopsis>
|
|
<funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>
|
|
|
|
<funcprototype>
|
|
<funcdef>int <function>sd_bus_start</function></funcdef>
|
|
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
|
|
</funcprototype>
|
|
</funcsynopsis>
|
|
</refsynopsisdiv>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para><function>sd_bus_start()</function> connects an existing bus connection object to the D-Bus
|
|
broker daemon, usually
|
|
<citerefentry project='die-net'><refentrytitle>dbus-daemon</refentrytitle><manvolnum>1</manvolnum></citerefentry>
|
|
or
|
|
<citerefentry project='mankier'><refentrytitle>dbus-broker</refentrytitle><manvolnum>1</manvolnum></citerefentry>.
|
|
The mechanism to use for the connection must be configured before the call to
|
|
<function>sd_bus_start()</function>, using one of
|
|
<citerefentry><refentrytitle>sd_bus_set_address</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>sd_bus_set_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>, or
|
|
<citerefentry><refentrytitle>sd_bus_set_exec</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
|
|
<function>sd_bus_start()</function> will open the connection socket or spawn the executable as
|
|
needed, and asynchronously start a <function>org.freedesktop.DBus.Hello()</function> call. The
|
|
answer to the Hello call will be processed later from
|
|
<citerefentry><refentrytitle>sd_bus_process</refentrytitle><manvolnum>3</manvolnum></citerefentry>. If
|
|
opening of the connection or queuing of the asynchronous call fail, the connection will be closed with
|
|
<citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
|
|
|
|
<para>In most cases, it is better to use
|
|
<citerefentry><refentrytitle>sd_bus_default_user</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
|
|
<citerefentry><refentrytitle>sd_bus_default_system</refentrytitle><manvolnum>3</manvolnum></citerefentry>
|
|
or related calls instead of the more low-level <function>sd_bus_new()</function> and
|
|
<function>sd_bus_start()</function>. The higher-level functions not only allocate a bus object but also
|
|
start the connection to a well-known bus in a single function call.</para>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Return Value</title>
|
|
|
|
<para>On success, this function returns a non-negative integer. On failure, it returns a negative
|
|
errno-style error code.</para>
|
|
|
|
<refsect2 id='errors'>
|
|
<title>Errors</title>
|
|
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><constant>-EINVAL</constant></term>
|
|
|
|
<listitem><para>The input parameter <parameter>bus</parameter> is <constant>NULL</constant>.
|
|
</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v246"/></listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ENOPKG</constant></term>
|
|
|
|
<listitem><para>Bus object <parameter>bus</parameter> could not be resolved.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v246"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-EPERM</constant></term>
|
|
|
|
<listitem><para>The input parameter <parameter>bus</parameter> is in a wrong state
|
|
(<function>sd_bus_start()</function> may only be called once on a newly-created bus object).</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v246"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
|
|
<varlistentry>
|
|
<term><constant>-ECHILD</constant></term>
|
|
|
|
<listitem><para>The bus object <parameter>bus</parameter> was created in a different
|
|
process.</para>
|
|
|
|
<xi:include href="version-info.xml" xpointer="v246"/>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
|
|
<para>In addition, other connection-related errors may be returned. See
|
|
<citerefentry><refentrytitle>sd_bus_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
|
|
</refsect2>
|
|
</refsect1>
|
|
|
|
<xi:include href="libsystemd-pkgconfig.xml" />
|
|
|
|
<refsect1>
|
|
<title>History</title>
|
|
<para><function>sd_bus_start()</function> was added in version 246.</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>
|
|
<member><citerefentry><refentrytitle>sd_bus_default</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
|
|
<member><citerefentry><refentrytitle>sd_bus_call_async</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
|
|
</simplelist></para>
|
|
</refsect1>
|
|
|
|
</refentry>
|