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diff --git a/man/sd_bus_attach_event.xml b/man/sd_bus_attach_event.xml new file mode 100644 index 0000000..bb34d4a --- /dev/null +++ b/man/sd_bus_attach_event.xml @@ -0,0 +1,119 @@ +<?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_attach_event" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_attach_event</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_attach_event</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_attach_event</refname> + <refname>sd_bus_detach_event</refname> + <refname>sd_bus_get_event</refname> + + <refpurpose>Attach a bus connection object to an event loop</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_attach_event</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>sd_event *<parameter>e</parameter></paramdef> + <paramdef>int <parameter>priority</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>int <function>sd_bus_detach_event</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + </funcprototype> + + <funcprototype> + <funcdef>sd_event *<function>sd_bus_get_event</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_bus_attach_event()</function> attaches the specified bus connection object to an + <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry> event loop object at + the specified priority (see + <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry> + for details on event loop priorities). When a bus connection object is attached to an event loop incoming messages + will be automatically read and processed, and outgoing messages written, whenever the event loop is run. When the + event loop is about to terminate, the bus connection is automatically flushed and closed (see + <citerefentry><refentrytitle>sd_bus_set_close_on_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry> for + details on this). By default bus connection objects are not attached to any event loop. When a bus connection + object is attached to one it is not necessary to invoke + <citerefentry><refentrytitle>sd_bus_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry> or + <citerefentry><refentrytitle>sd_bus_process</refentrytitle><manvolnum>3</manvolnum></citerefentry> as this + functionality is handled automatically by the event loop.</para> + + <para><function>sd_bus_detach_event()</function> detaches a bus object from its event loop.</para> + + <para>The <function>sd_bus_get_event()</function> returns the event loop object the specified bus object is + currently attached to, or <constant>NULL</constant> if it is currently not attached to any.</para> + + <para>Note that <function>sd_bus_attach_event()</function> is only one of three supported ways to implement I/O + event handling for bus connections. Alternatively use + <citerefentry><refentrytitle>sd_bus_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry> for hooking up a + bus connection object with external or manual event loops. Or use + <citerefentry><refentrytitle>sd_bus_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry> as a simple + synchronous, blocking I/O waiting call.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On success, <function>sd_bus_attach_event()</function> and <function>sd_bus_detach_event()</function> return + 0 or a positive integer. On failure, they return a negative errno-style error code.</para> + + <para><function>sd_bus_get_event()</function> returns an event loop object or <constant>NULL</constant>.</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.</para></listitem> + </varlistentry> + </variablelist> + </refsect2> + </refsect1> + + <xi:include href="libsystemd-pkgconfig.xml" /> + + <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-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_set_close_on_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |