systemd/man/sd_bus_message_append_array.xml
Lennart Poettering 3802a3d3d7 man: add emacs header to get correct indention in nxml-mode for the manpage XML files that use 2ch indenting
In the long run we really should figure out if we want to stick with 8ch
or 2ch indenting, and not continue with half-and-half. For now, just
make emacs aware of the files that use 2ch indenting.
2014-11-21 20:44:48 +01:00

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<?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
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You should have received a copy of the GNU Lesser General Public License
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-->
<refentry id="sd_bus_message_append_array" conditional="ENABLE_KDBUS"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_bus_message_append_array</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_array</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_bus_message_append_array</refname>
<refname>sd_bus_message_append_array_memfd</refname>
<refname>sd_bus_message_append_array_iovec</refname>
<refname>sd_bus_message_append_array_space</refname>
<refpurpose>Attach an array of items to a message</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int sd_bus_message_append_array</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>char <parameter>type</parameter></paramdef>
<paramdef>char void *<parameter>ptr</parameter></paramdef>
<paramdef>size_t <parameter>size</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_append_array_memfd</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>char <parameter>type</parameter></paramdef>
<paramdef>int <parameter>memfd</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_append_array_iovec</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>char <parameter>type</parameter></paramdef>
<paramdef>const struct iovec *<parameter>iov</parameter></paramdef>
<paramdef>unsigned <parameter>n</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_append_array_space</funcdef>
<paramdef>char <parameter>type</parameter></paramdef>
<paramdef>size_t <parameter>size</parameter></paramdef>
<paramdef>char void **<parameter>ptr</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>The <function>sd_bus_message_append_array</function> functionc
appends items to message <parameter>m</parameter> as the single
array. A container will be opened, items appended, and the
container closed. Parameter <parameter>type</parameter> determines
how pointer <parameter>p</parameter> is interpreted.
<parameter>type</parameter> must be one of the "trivial" types
<literal>y</literal>, <literal>n</literal>, <literal>q</literal>,
<literal>i</literal>, <literal>u</literal>, <literal>x</literal>,
<literal>t</literal>, <literal>d</literal> (but not
<literal>b</literal>), 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
<citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
Pointer <parameter>p</parameter> must point to an array of size
<parameter>size</parameter> bytes containing items of the
respective type. Size <parameter>size</parameter> must be a
multiple of the size of the type <parameter>type</parameter>. As a
special case, <parameter>p</parameter> may be
<constant>NULL</constant>, if <parameter>size</parameter> is 0.
</para>
<para>The memory pointed at by <parameter>p</parameter> is copied
into the memory area containing the message and may be changed
after this call.</para>
<para>The
<function>sd_bus_message_append_array_memfd</function> function appends
items to message <parameter>m</parameter>, similarly to
<function>sd_bus_message_append_array</function>. Contents of the
memory file descriptor <parameter>memfd</parameter> are used as
the contents of the array. Their size must be a multiple of the
size of the type <parameter>type</parameter>.</para>
<para>The descriptor specified with <parameter>memfd</parameter>
will be sealed and cannot be modified after this call.</para>
<para>The
<function>sd_bus_message_append_array_iovec</function> function appends
items to message <parameter>m</parameter>, similarly to
<function>sd_bus_message_append_array</function>. Contents of the
iovec <parameter>iov</parameter> are used as the contents of the
array. The total size of <parameter>iov</parameter> payload (the
sum of <structfield>iov_len</structfield> fields) must be a multiple
of the size of the type <parameter>type</parameter>.</para>
<para>The <parameter>iov</parameter> argument must point to
<parameter>n</parameter> <structname>struct iovec</structname>
structures. Each structure may have the
<structname>iov_base</structname> field set, in which case the
memory pointed to will be copied into the message, or unset, in
which case a block of zeros of length
<structname>iov_len</structname> bytes will be inserted. The
memory pointed at by <parameter>iov</parameter> may be changed
after this call.</para>
<para>The
<function>sd_bus_message_append_array_space</function> function appends
space for an array of items to message <parameter>m</parameter>.
It behaves the same as
<function>sd_bus_message_append_array</function>, but instead
of copying items to the message, it returns a pointer to the
destination area to the caller in pointer <parameter>p</parameter>.
</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para>On success, these calls return 0 or a positive integer. On
failure, they returns a negative errno-style error code.</para>
</refsect1>
<xi:include href="sd_bus_message_append_basic.xml" xpointer="errors" />
<refsect1>
<title>Notes</title>
<para><function>sd_bus_append_array()</function> and other
functions described here are available as a shared library, which
can be compiled and linked to with the
<constant>libsystemd</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>,
<citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html">The D-Bus specification</ulink>
</para>
</refsect1>
</refentry>