man/sd_bus_message_set_expect_reply.xml

   1 <?xml version='1.0'?> <!--*-nxml-*-->
   2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
   4 <!-- SPDX-License-Identifier: LGPL-2.1-or-later -->
   5
   6 <refentry id="sd_bus_message_set_expect_reply" xmlns:xi="http://www.w3.org/2001/XInclude">
   7
   8   <refentryinfo>
   9     <title>sd_bus_message_set_expect_reply</title>
  10     <productname>systemd</productname>
  11   </refentryinfo>
  12
  13   <refmeta>
  14     <refentrytitle>sd_bus_message_set_expect_reply</refentrytitle>
  15     <manvolnum>3</manvolnum>
  16   </refmeta>
  17
  18   <refnamediv>
  19     <refname>sd_bus_message_set_expect_reply</refname>
  20     <refname>sd_bus_message_get_expect_reply</refname>
  21     <refname>sd_bus_message_set_auto_start</refname>
  22     <refname>sd_bus_message_get_auto_start</refname>
  23     <refname>sd_bus_message_set_allow_interactive_authorization</refname>
  24     <refname>sd_bus_message_get_allow_interactive_authorization</refname>
  25
  26     <refpurpose>Set and query bus message metadata</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_message_set_expect_reply</function></funcdef>
  35         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  36         <paramdef>int <parameter>b</parameter></paramdef>
  37       </funcprototype>
  38
  39       <funcprototype>
  40         <funcdef>int <function>sd_bus_message_get_expect_reply</function></funcdef>
  41         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  42       </funcprototype>
  43
  44       <funcprototype>
  45         <funcdef>int <function>sd_bus_message_set_auto_start</function></funcdef>
  46         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  47         <paramdef>int <parameter>b</parameter></paramdef>
  48       </funcprototype>
  49
  50       <funcprototype>
  51         <funcdef>int <function>sd_bus_message_get_auto_start</function></funcdef>
  52         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  53       </funcprototype>
  54
  55       <funcprototype>
  56         <funcdef>int <function>sd_bus_message_set_allow_interactive_authorization</function></funcdef>
  57         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  58         <paramdef>int <parameter>b</parameter></paramdef>
  59       </funcprototype>
  60
  61       <funcprototype>
  62         <funcdef>int <function>sd_bus_message_get_allow_interactive_authorization</function></funcdef>
  63         <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
  64       </funcprototype>
  65     </funcsynopsis>
  66   </refsynopsisdiv>
  67
  68   <refsect1>
  69     <title>Description</title>
  70
  71     <para><function>sd_bus_message_set_expect_reply()</function> sets or clears the
  72     <constant>NO_REPLY_EXPECTED</constant> flag on the message <parameter>m</parameter>. This flag matters
  73     only for method call messages and is used to specify that no method return or error reply is expected.
  74     It is ignored for other types. Thus, for a method call message, calling
  75     <programlisting>sd_bus_message_set_expect_reply(…, 0)</programlisting> sets the flag and suppresses the
  76     reply.</para>
  77
  78     <para><function>sd_bus_message_get_expect_reply()</function> checks if the
  79     <constant>NO_REPLY_EXPECTED</constant> flag is set on the message <parameter>m</parameter>. It will
  80     return positive if it is not set, and zero if it is.</para>
  81
  82     <para><function>sd_bus_message_set_auto_start()</function> sets or clears the
  83     <constant>NO_AUTO_START</constant> flag on the message <parameter>m</parameter>. When the flag is set,
  84     the bus must not launch an owner for the destination name in response to this message. Calling
  85     <programlisting>sd_bus_message_set_auto_start(…, 0)</programlisting> sets the flag.</para>
  86
  87     <para><function>sd_bus_message_get_auto_start()</function> checks if the
  88     <constant>NO_AUTO_START</constant> flag is set on the message <parameter>m</parameter>. It will return
  89     positive if it is not set, and zero if it is.</para>
  90
  91     <para><function>sd_bus_message_set_allow_interactive_authorization()</function> sets or clears the
  92     <constant>ALLOW_INTERACTIVE_AUTHORIZATION</constant> flag on the message <parameter>m</parameter>.
  93     Setting this flag informs the receiver that the caller is prepared to wait for interactive authorization
  94     via polkit or a similar framework. Note that setting this flag does not guarantee that the receiver will
  95     actually perform interactive authorization. Also, make sure to set a suitable message timeout when using
  96     this flag since interactive authorization could potentially take a long time as it depends on user input.
  97     If <parameter>b</parameter> is non-zero, the flag is set.</para>
  98
  99     <para><function>sd_bus_message_get_allow_interactive_authorization()</function> checks if the
 100     <constant>ALLOW_INTERACTIVE_AUTHORIZATION</constant> flag is set on the message <parameter>m</parameter>.
 101     It will return a positive integer if the flag is set. Otherwise, it returns zero.</para>
 102   </refsect1>
 103
 104   <refsect1>
 105     <title>Return Value</title>
 106
 107     <para>On success, these functions return a non-negative integer. On failure, they return a negative
 108     errno-style error code.</para>
 109
 110     <refsect2>
 111       <title>Errors</title>
 112
 113       <para>Returned errors may indicate the following problems:</para>
 114
 115       <variablelist>
 116         <varlistentry>
 117           <term><constant>-EINVAL</constant></term>
 118
 119           <listitem><para>The <parameter>message</parameter> parameter is <constant>NULL</constant>.
 120           </para></listitem>
 121         </varlistentry>
 122
 123         <varlistentry>
 124           <term><constant>-EPERM</constant></term>
 125
 126           <listitem>
 127           <para>The message <parameter>message</parameter> is sealed when trying to set a flag.</para>
 128
 129           <para>The message <parameter>message</parameter> has wrong type.</para>
 130           </listitem>
 131         </varlistentry>
 132       </variablelist>
 133     </refsect2>
 134   </refsect1>
 135
 136   <xi:include href="libsystemd-pkgconfig.xml" />
 137
 138   <refsect1>
 139     <title>History</title>
 140     <para><function>sd_bus_message_set_expect_reply()</function>,
 141     <function>sd_bus_message_get_expect_reply()</function>,
 142     <function>sd_bus_message_set_auto_start()</function>, and
 143     <function>sd_bus_message_get_auto_start()</function> were added in version 240.</para>
 144     <para><function>sd_bus_message_set_allow_interactive_authorization()</function> and
 145     <function>sd_bus_message_get_allow_interactive_authorization()</function> were added in version 246.</para>
 146   </refsect1>
 147
 148   <refsect1>
 149     <title>See Also</title>
 150
 151     <para><simplelist type="inline">
 152       <member><citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry></member>
 153       <member><citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
 154       <member><citerefentry><refentrytitle>sd_bus_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry></member>
 155     </simplelist></para>
 156   </refsect1>
 157 </refentry>