summaryrefslogtreecommitdiffstats
path: root/man/sd_bus_attach_event.xml
diff options
context:
space:
mode:
Diffstat (limited to 'man/sd_bus_attach_event.xml')
-rw-r--r--man/sd_bus_attach_event.xml126
1 files changed, 126 insertions, 0 deletions
diff --git a/man/sd_bus_attach_event.xml b/man/sd_bus_attach_event.xml
new file mode 100644
index 0000000..979783c
--- /dev/null
+++ b/man/sd_bus_attach_event.xml
@@ -0,0 +1,126 @@
+<?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 &lt;systemd/sd-bus.h&gt;</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, library or module instance.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
+ </refsect1>
+
+ <xi:include href="libsystemd-pkgconfig.xml" />
+
+ <refsect1>
+ <title>History</title>
+ <para><function>sd_bus_attach_event()</function>,
+ <function>sd_bus_detach_event()</function>, and
+ <function>sd_bus_get_event()</function> were added in version 240.</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-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>