--- /dev/null
+<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
+<!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 systemd.
+
+ Copyright 2014 Zbigniew Jędrzejewski-Szmek
+
+ systemd 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.
+
+ systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_bus_message_append_basic">
+
+ <refentryinfo>
+ <title>sd_bus_message_append_basic</title>
+ <productname>systemd</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>A monkey with a typewriter</contrib>
+ <firstname>Zbigniew</firstname>
+ <surname>Jędrzejewski-Szmek</surname>
+ <email>zbyszek@in.waw.pl</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_bus_message_append_basic</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_bus_message_append_basic</refname>
+
+ <refpurpose>Attach a single field to a message</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int sd_bus_message_append_basic</funcdef>
+ <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
+ <paramdef>char <parameter>type</parameter></paramdef>
+ <paramdef>const void *<parameter>p</parameter></paramdef>
+ </funcprototype>
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_bus_message_append_basic()</function> appends a
+ single field to the message <parameter>m</parameter>. The
+ parameter <parameter>type</parameter> determines how the pointer
+ <parameter>p</parameter> is interpreted.
+ <parameter>type</parameter> must be one of the basic types as
+ defined by the <ulink
+ url="http://dbus.freedesktop.org/doc/dbus-specification.html#basic-types">Basic
+ Types</ulink> section of the D-Bus specification, and listed in
+ the table below.
+ </para>
+
+ <table id='format-specifiers'>
+ <title>Item type specifiers</title>
+
+ <tgroup cols='5'>
+ <colspec colname='specifier' />
+ <colspec colname='constant' />
+ <colspec colname='description' />
+ <colspec colname='size' />
+ <colspec colname='ctype' />
+ <thead>
+ <row>
+ <entry>Specifier</entry>
+ <entry>Constant</entry>
+ <entry>Description</entry>
+ <entry>Size</entry>
+ <entry>Expected C Type</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry><literal>y</literal></entry>
+ <entry><constant>SD_BUS_TYPE_BYTE</constant></entry>
+ <entry>unsigned integer</entry>
+ <entry>1 byte</entry>
+ <entry>uint8_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>b</literal></entry>
+ <entry><constant>SD_BUS_TYPE_BOOLEAN</constant></entry>
+ <entry>boolean</entry>
+ <entry>4 bytes</entry>
+ <entry>int</entry>
+ </row>
+
+ <row>
+ <entry><literal>n</literal></entry>
+ <entry><constant>SD_BUS_TYPE_INT16</constant></entry>
+ <entry>signed integer</entry>
+ <entry>2 bytes</entry>
+ <entry>int16_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>q</literal></entry>
+ <entry><constant>SD_BUS_TYPE_UINT16</constant></entry>
+ <entry>unsigned integer</entry>
+ <entry>2 bytes</entry>
+ <entry>uint16_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>i</literal></entry>
+ <entry><constant>SD_BUS_TYPE_INT32</constant></entry>
+ <entry>signed integer</entry>
+ <entry>4 bytes</entry>
+ <entry>int32_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>u</literal></entry>
+ <entry><constant>SD_BUS_TYPE_UINT32</constant></entry>
+ <entry>unsigned integer</entry>
+ <entry>4 bytes</entry>
+ <entry>uint32_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>x</literal></entry>
+ <entry><constant>SD_BUS_TYPE_INT64</constant></entry>
+ <entry>signed integer</entry>
+ <entry>8 bytes</entry>
+ <entry>int64_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>t</literal></entry>
+ <entry><constant>SD_BUS_TYPE_UINT64</constant></entry>
+ <entry>unsigned integer</entry>
+ <entry>8 bytes</entry>
+ <entry>uint64_t</entry>
+ </row>
+
+ <row>
+ <entry><literal>d</literal></entry>
+ <entry><constant>SD_BUS_TYPE_DOUBLE</constant></entry>
+ <entry>floating-point</entry>
+ <entry>8 bytes</entry>
+ <entry>double</entry>
+ </row>
+
+ <row>
+ <entry><literal>s</literal></entry>
+ <entry><constant>SD_BUS_TYPE_STRING</constant></entry>
+ <entry>Unicode string</entry>
+ <entry>variable</entry>
+ <entry>char[]</entry>
+ </row>
+
+ <row>
+ <entry><literal>o</literal></entry>
+ <entry><constant>SD_BUS_TYPE_OBJECT_PATH</constant></entry>
+ <entry>object path</entry>
+ <entry>variable</entry>
+ <entry>char[]</entry>
+ </row>
+
+ <row>
+ <entry><literal>g</literal></entry>
+ <entry><constant>SD_BUS_TYPE_SIGNATURE</constant></entry>
+ <entry>signature</entry>
+ <entry>variable</entry>
+ <entry>char[]</entry>
+ </row>
+
+ <row>
+ <entry><literal>h</literal></entry>
+ <entry><constant>SD_BUS_TYPE_UNIX_FD</constant></entry>
+ <entry>UNIX file descriptor</entry>
+ <entry>4 bytes</entry>
+ <entry>int</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+
+ <para>The value of the parameter is copied into a memory area held
+ by the message object, stays in the possession of the caller and
+ may hence be freely changed after this call without affecting the
+ bus message it has been added to. If <parameter>type</parameter>
+ is <literal>h</literal> (UNIX file descriptor), the descriptor is
+ duplicated by this call and the passed descriptor stays in
+ possession of the caller.</para>
+
+ <para>For types <literal>s</literal>, <literal>o</literal>, and
+ <literal>g</literal>, the parameter <parameter>p</parameter> is
+ interpreted as a pointer to a <constant>NUL</constant>-terminated
+ character sequence. As a special case, a <constant>NULL</constant>
+ pointer is interpreted as an empty string. The string should be
+ valid Unicode string encoded as UTF-8. In case of the two latter
+ types, the additional requirements for a D-Bus object path or
+ type signature should be satisfied. Those requirements should be
+ verified by the recipient of the message.
+ </para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, this call returns 0 or a positive integer. On
+ failure, it returns a negative errno-style error code.</para>
+ </refsect1>
+
+ <refsect1 id='errors'>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>Specified parameter is invalid.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EPERM</constant></term>
+
+ <listitem><para>Message has been sealed.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>Message is in invalid state.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENXIO</constant></term>
+
+ <listitem><para>Message cannot be appended to.
+ </para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Memory allocation failed.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Notes</title>
+
+ <para>The <function>sd_bus_append_basic()</function> function
+ described here is 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>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_bus_message_append</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html">The D-Bus specification</ulink>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / blobdiff