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<?xml version='1.0'?>
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< !DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
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<!-- SPDX - License - Identifier: LGPL - 2.1 - or - later -->
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<refentry id= "sd_bus_set_connected_signal"
xmlns:xi="http://www.w3.org/2001/XInclude">
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<refentryinfo >
<title > sd_bus_set_connected_signal</title>
<productname > systemd</productname>
</refentryinfo>
<refmeta >
<refentrytitle > sd_bus_set_connected_signal</refentrytitle>
<manvolnum > 3</manvolnum>
</refmeta>
<refnamediv >
<refname > sd_bus_set_connected_signal</refname>
<refname > sd_bus_get_connected_signal</refname>
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<refpurpose > Control emission of local connection establishment signal on bus connections</refpurpose>
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</refnamediv>
<refsynopsisdiv >
<funcsynopsis >
<funcsynopsisinfo > #include < systemd/sd-bus.h> </funcsynopsisinfo>
<funcprototype >
<funcdef > int <function > sd_bus_set_connected_signal</function> </funcdef>
<paramdef > sd_bus *<parameter > bus</parameter> </paramdef>
<paramdef > int <parameter > b</parameter> </paramdef>
</funcprototype>
<funcprototype >
<funcdef > int <function > sd_bus_get_connected_signal</function> </funcdef>
<paramdef > sd_bus *<parameter > bus</parameter> </paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 >
<title > Description</title>
<para > <function > sd_bus_set_connected_signal()</function> may be used to control whether a local, synthetic
<function > Connected()</function> signal message shall be generated and enqueued for dispatching when the connection
is fully established. If the <parameter > b</parameter> parameter is zero the message is not generated (the default),
otherwise it is generated.</para>
<para > <function > sd_bus_get_connected_signal()</function> may be used to query whether this feature is enabled. It
returns zero if not, positive otherwise.</para>
<para > The <function > Connected()</function> signal message is generated from the
<literal > org.freedesktop.DBus.Local</literal> service and interface, and
<literal > /org/freedesktop/DBus/Local</literal> object path. Use
<citerefentry > <refentrytitle > sd_bus_match_signal_async</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry> to
match on this signal.</para>
<para > This message is particularly useful on slow transports where connections take a long time to be
established. This is especially the case when
<citerefentry > <refentrytitle > sd_bus_set_watch_bind</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry> is
used. The signal is generated when the
<citerefentry > <refentrytitle > sd_bus_is_ready</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry> returns
positive for the first time.</para>
<para > The <function > Connected()</function> signal corresponds with the <function > Disconnected()</function> signal
that is synthesized locally when the connection is terminated. The latter is generated unconditionally however,
unlike the former which needs to be enabled explicitly before it is generated, with
<function > sd_bus_set_connected_signal()</function> .</para>
</refsect1>
<refsect1 >
<title > Return Value</title>
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<para > On success, these functions return 0 or a positive integer. On failure, they return a negative
errno-style error code.</para>
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<refsect2 >
<title > Errors</title>
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<para > Returned errors may indicate the following problems:</para>
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<variablelist >
<varlistentry >
<term > <constant > -ECHILD</constant> </term>
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<listitem > <para > The bus connection has been created in a different process, library or module instance.</para> </listitem>
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</varlistentry>
</variablelist>
</refsect2>
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</refsect1>
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<xi:include href= "libsystemd-pkgconfig.xml" />
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<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_match_signal_async</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry> ,
<citerefentry > <refentrytitle > sd_bus_set_watch_bind</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry> ,
<citerefentry > <refentrytitle > sd_bus_is_ready</refentrytitle> <manvolnum > 3</manvolnum> </citerefentry>
</para>
</refsect1>
</refentry>