man/sd_bus_set_close_on_exit.xml

   1 <?xml version='1.0'?>
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
   3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
   4
   5 <!--
   6   SPDX-License-Identifier: LGPL-2.1+
   7 -->
   8
   9 <refentry id="sd_bus_set_close_on_exit"
  10           xmlns:xi="http://www.w3.org/2001/XInclude">
  11
  12   <refentryinfo>
  13     <title>sd_bus_set_close_on_exit</title>
  14     <productname>systemd</productname>
  15   </refentryinfo>
  16
  17   <refmeta>
  18     <refentrytitle>sd_bus_set_close_on_exit</refentrytitle>
  19     <manvolnum>3</manvolnum>
  20   </refmeta>
  21
  22   <refnamediv>
  23     <refname>sd_bus_set_close_on_exit</refname>
  24     <refname>sd_bus_get_close_on_exit</refname>
  25
  26     <refpurpose>Control whether to close the bus connection during the event loop exit phase</refpurpose>
  27   </refnamediv>
  28
  29   <refsynopsisdiv>
  30     <funcsynopsis>
  31       <funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
  32
  33       <funcprototype>
  34         <funcdef>int <function>sd_bus_set_close_on_exit</function></funcdef>
  35         <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
  36         <paramdef>int <parameter>b</parameter></paramdef>
  37       </funcprototype>
  38
  39       <funcprototype>
  40         <funcdef>int <function>sd_bus_get_close_on_exit</function></funcdef>
  41         <paramdef>sd_bus *<parameter>bus</parameter></paramdef>
  42       </funcprototype>
  43
  44     </funcsynopsis>
  45   </refsynopsisdiv>
  46
  47   <refsect1>
  48     <title>Description</title>
  49
  50     <para><function>sd_bus_set_close_on_exit()</function> may be used to enable or disable whether the bus connection
  51     is automatically flushed (as in
  52     <citerefentry><refentrytitle>sd_bus_flush</refentrytitle><manvolnum>3</manvolnum></citerefentry>) and closed (as in
  53     <citerefentry><refentrytitle>sd_bus_close</refentrytitle><manvolnum>3</manvolnum></citerefentry>) during the exit
  54     phase of the event loop. This logic only applies to bus connections that are attached to an
  55     <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry> event loop, see
  56     <citerefentry><refentrytitle>sd_bus_attach_event</refentrytitle><manvolnum>3</manvolnum></citerefentry>. By default
  57     this mechanism is enabled and makes sure that any pending messages that have not been written to the bus connection
  58     are written out when the event loop is shutting down. In some cases this behaviour is not desirable, for example
  59     when the bus connection shall remain usable until after the event loop exited. If <parameter>b</parameter> is
  60     true, the feature is enabled (which is the default), otherwise disabled.</para>
  61
  62     <para><function>sd_bus_get_close_on_exit()</function> may be used to query the current setting of this feature. It
  63     returns zero when the feature is disabled, and positive if enabled.</para>
  64   </refsect1>
  65
  66   <refsect1>
  67     <title>Return Value</title>
  68
  69     <para>On success, <function>sd_bus_set_close_on_exit()</function> returns 0 or a positive integer. On failure, it returns a negative errno-style
  70     error code.</para>
  71
  72     <para><function>sd_bus_get_close_on_exit()</function> returns 0 if the feature is currently turned off or a
  73     positive integer if it is on. On failure, it returns a negative errno-style error code.</para>
  74   </refsect1>
  75
  76   <refsect1>
  77     <title>Errors</title>
  78
  79     <para>Returned errors may indicate the following problems:</para>
  80
  81     <variablelist>
  82       <varlistentry>
  83         <term><constant>-ECHILD</constant></term>
  84
  85         <listitem><para>The bus connection has been created in a different process.</para></listitem>
  86       </varlistentry>
  87     </variablelist>
  88   </refsect1>
  89
  90   <xi:include href="libsystemd-pkgconfig.xml" />
  91
  92   <refsect1>
  93     <title>See Also</title>
  94
  95     <para>
  96       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  97       <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
  98       <citerefentry><refentrytitle>sd_bus_flush</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
  99       <citerefentry><refentrytitle>sd_bus_attach_event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 100       <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
 101       <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
 102     </para>
 103   </refsect1>
 104
 105 </refentry>