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<?xml version='1.0'?> <!--*-nxml-*-->
<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
<!--
This file is part of systemd.
Copyright 2014 Zbigniew Jędrzejewski-Szmek
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
-->
<refentry id="sd_bus_new">
<refentryinfo>
<title>sd_bus_new</title>
<productname>systemd</productname>
<authorgroup>
<author>
<contrib>A monkey with a typewriter</contrib>
<firstname>Zbigniew</firstname>
<surname>Jędrzejewski-Szmek</surname>
<email>zbyszek@in.waw.pl</email>
</author>
</authorgroup>
</refentryinfo>
<refmeta>
<refentrytitle>sd_bus_new</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_bus_new</refname>
<refname>sd_bus_ref</refname>
<refname>sd_bus_unref</refname>
<refpurpose>Create a new bus object and create or destroy references to it</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>sd_bus_new</function></funcdef>
<paramdef>sd_bus** <parameter>bus</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>sd_bus* <function>sd_bus_ref</function></funcdef>
<paramdef>sd_bus* <parameter>bus</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>sd_bus* <function>sd_bus_unref</function></funcdef>
<paramdef>sd_bus* <parameter>bus</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><function>sd_bus_new()</function> creates a new bus
object. This object is reference counted, and will be destroyed
when all references are gone. Initially, the caller of this
function owns the sole reference.</para>
<para><function>sd_bus_ref()</function> creates a new reference to
<parameter>bus</parameter>. This bus object will not be destroyed
until <function>sd_bus_unref()</function> has been called as many
times plus once more. Once the reference count has dropped to
zero, <parameter>bus</parameter> cannot be used anymore, so
further calls to <function>sd_bus_ref()</function> or
<function>sd_bus_unref()</function> are illegal.</para>
<para><function>sd_bus_unref()</function> destroys a reference to
<parameter>bus</parameter>.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para>On success, <function>sd_bus_new()</function> returns 0 or a
positive integer. On failure, it returns a negative errno-style
error code.</para>
<para><function>sd_bus_ref</function> always returns the argument.
</para>
<para><function>sd_bus_unref</function> always returns
<constant>NULL</constant>.</para>
</refsect1>
<refsect1>
<title>Errors</title>
<para>Returned errors may indicate the following problems:</para>
<variablelist>
<varlistentry>
<term><varname>-ENOMEM</varname></term>
<listitem><para>Memory allocation failed.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para><function>sd_bus_new()</function> and other functions
described here are available as a shared library, which can be
compiled and linked to with the
<constant>libsystemd-bus</constant> <citerefentry><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
file.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_open_user</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_open_system</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_default_user</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_default_system</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>
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