--- /dev/null
+<?xml version='1.0'?> <!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+ "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+ This file is part of elogind.
+
+ Copyright 2013 Lennart Poettering
+
+ elogind is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ elogind is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_bus_message_get_cookie">
+
+ <refentryinfo>
+ <title>sd_bus_message_get_cookie</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_bus_message_get_cookie</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_bus_message_get_cookie</refname>
+ <refname>sd_bus_message_get_reply_cookie</refname>
+ <refpurpose>Returns the transaction cookie of a message</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-bus.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_bus_message_get_cookie</function></funcdef>
+ <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
+ <paramdef>uint64_t *<parameter>cookie</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_bus_message_get_reply_cookie</function></funcdef>
+ <paramdef>sd_bus_message *<parameter>message</parameter></paramdef>
+ <paramdef>uint64_t *<parameter>cookie</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_bus_message_get_cookie()</function> returns the
+ transaction cookie of a message. The cookie uniquely identifies a
+ message within each bus peer, but is not globally unique. It is
+ assigned when a message is sent.</para>
+
+ <para><function>sd_bus_message_get_reply_cookie()</function>
+ returns the transaction cookie of the message the specified
+ message is a response to. When a reply message is generated for a
+ method call message, its cookie is copied over into this field.
+ Note that while every message that is transferred is identified by
+ a cookie, only response messages carry a reply cookie
+ field.</para>
+
+ <para>Both functions take a message object as first parameter and
+ a place to store the 64-bit cookie in.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, these calls return 0 or a positive integer. On
+ failure, these calls return a negative errno-style error
+ code.</para>
+
+ <para>On success, the cookie/reply cookie is returned in the
+ specified 64-bit unsigned integer variable.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>A specified parameter
+ is invalid.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENODATA</constant></term>
+
+ <listitem><para>No cookie has been assigned to this message.
+ This either indicates that the message has not been sent yet
+ and hence has no cookie assigned, or that the message is not a
+ method response message and hence carries a reply cookie
+ field.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>The <function>sd_bus_message_get_cookie()</function> and
+ <function>sd_bus_message_get_reply_cookie()</function> interfaces
+ are available as a shared library, which can be compiled and
+ linked to with the
+ <constant>libelogind</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ file.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_bus_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / blobdiff