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diff --git a/man/sd_bus_is_open.xml b/man/sd_bus_is_open.xml new file mode 100644 index 0000000..586d1f6 --- /dev/null +++ b/man/sd_bus_is_open.xml @@ -0,0 +1,112 @@ +<?xml version='1.0'?> +<!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_is_open" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_is_open</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_is_open</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_is_open</refname> + <refname>sd_bus_is_ready</refname> + + <refpurpose>Check whether the bus connection is open or ready</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_is_open</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_is_ready</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + </funcprototype> + + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_bus_is_open()</function> checks whether the specified bus connection is open, i.e. in the + process of being established, already established or in the process of being torn down. It returns zero when the + connection has not been started yet + (i.e. <citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry> or some + equivalent call has not been invoked yet), or is fully terminated again (for example after + <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>), it returns + positive otherwise.</para> + + <para><function>sd_bus_is_ready()</function> checks whether the specified connection is fully established, + i.e. completed the connection and authentication phases of the protocol and received the + <function>Hello()</function> method call response, and is not in the process of being torn down again. It returns + zero outside of this state, and positive otherwise. Effectively, this function returns positive while regular + messages can be sent or received on the connection.</para> + + <para>The <parameter>bus</parameter> argument may be <constant>NULL</constant>, zero is also returned in + that case.</para> + + <para>To be notified when the connection is fully established, use + <citerefentry><refentrytitle>sd_bus_set_connected_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry> and + install a match for the <function>Connected()</function> signal on the + <literal>org.freedesktop.DBus.Local</literal> interface. To be notified when the connection is torn down again, + install a match for the <function>Disconnected()</function> signal on the + <literal>org.freedesktop.DBus.Local</literal> interface.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>Those functions return 0 if the bus is <emphasis>not</emphasis> in the given state, and a positive + integer when it is. On failure, a negative errno-style error code is returned.</para> + + <refsect2> + <title>Errors</title> + + <para>Returned errors may indicate the following problems:</para> + + <variablelist> + <varlistentry> + <term><constant>-ECHILD</constant></term> + + <listitem><para>The bus connection has been created in a different process, library or module instance.</para></listitem> + </varlistentry> + </variablelist> + </refsect2> + </refsect1> + + <xi:include href="libsystemd-pkgconfig.xml" /> + + <refsect1> + <title>History</title> + <para><function>sd_bus_is_open()</function> and + <function>sd_bus_is_ready()</function> were added in version 237.</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_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_set_connected_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |