man/sd_bus_message_rewind.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 <!-- SPDX-License-Identifier: LGPL-2.1+ -->
   5
   6 <refentry id="sd_bus_message_rewind"
   7           xmlns:xi="http://www.w3.org/2001/XInclude">
   8
   9   <refentryinfo>
  10     <title>sd_bus_message_rewind</title>
  11     <productname>systemd</productname>
  12   </refentryinfo>
  13
  14   <refmeta>
  15     <refentrytitle>sd_bus_message_rewind</refentrytitle>
  16     <manvolnum>3</manvolnum>
  17   </refmeta>
  18
  19   <refnamediv>
  20     <refname>sd_bus_message_rewind</refname>
  21
  22     <refpurpose>Return to begining of message or current container</refpurpose>
  23   </refnamediv>
  24
  25   <refsynopsisdiv>
  26     <funcsynopsis>
  27       <funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
  28
  29       <funcprototype>
  30         <funcdef>int <function>sd_bus_message_rewind</function></funcdef>
  31         <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
  32         <paramdef>int <parameter>complete</parameter></paramdef>
  33       </funcprototype>
  34     </funcsynopsis>
  35   </refsynopsisdiv>
  36
  37   <refsect1>
  38     <title>Description</title>
  39
  40     <para><function>sd_bus_message_rewind()</function> moves the "read pointer" in the message
  41     <parameter>m</parameter> to either the begining of the message (if
  42     <parameter>complete</parameter> is true) or to the beginning of the currently open container. If
  43     no container is open, <parameter>complete</parameter> has no effect.</para>
  44   </refsect1>
  45
  46   <refsect1>
  47     <title>Return Value</title>
  48
  49     <para>
  50       On success, this function returns 0 or a positive integer. The value is zero if the current
  51       container or whole message in case no container is open is empty, and positive otherwise. On
  52       failure, it returns a negative errno-style error code.
  53     </para>
  54   </refsect1>
  55
  56   <xi:include href="libsystemd-pkgconfig.xml" />
  57
  58   <refsect1>
  59     <title>Errors</title>
  60
  61     <para>Returned errors may indicate the following problems:</para>
  62
  63     <variablelist>
  64       <varlistentry>
  65         <term><constant>-EINVAL</constant></term>
  66
  67         <listitem><para>The <parameter>m</parameter> parameter is <constant>NULL</constant>.</para></listitem>
  68       </varlistentry>
  69
  70       <varlistentry>
  71         <term><constant>-EPERM</constant></term>
  72
  73         <listitem><para>The message <parameter>m</parameter> has not been sealed.</para></listitem>
  74       </varlistentry>
  75     </variablelist>
  76   </refsect1>
  77
  78   <refsect1>
  79     <title>See Also</title>
  80
  81     <para>
  82       <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
  83       <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
  84       <citerefentry><refentrytitle>sd_bus_message_read</refentrytitle><manvolnum>3</manvolnum></citerefentry>
  85     </para>
  86   </refsect1>
  87
  88 </refentry>