systemd/man/sd_bus_message_append_string_memfd.xml
Zbigniew Jędrzejewski-Szmek 7d6b27238f man: xinclude the generic text to talk about libsystemd pkgconfig
The only difference is that functions are not individually listed by name,
but that seems completely pointless, since all functions that are documented
are always exported, so the generic text tells the user all she or he needs
to know.
2018-06-06 23:01:25 +02:00

136 lines
5.1 KiB
XML

<?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">
<!--
SPDX-License-Identifier: LGPL-2.1+
This file is part of systemd.
Copyright 2014 Zbigniew Jędrzejewski-Szmek
-->
<refentry id="sd_bus_message_append_string_memfd"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_bus_message_append_string_memfd</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_string_memfd</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_bus_message_append_string_memfd</refname>
<refname>sd_bus_message_append_string_iovec</refname>
<refname>sd_bus_message_append_string_space</refname>
<refpurpose>Attach a string to a message</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int sd_bus_message_append_string_memfd</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>int <parameter>memfd</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_append_string_iovec</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>const struct iovec *<parameter>iov</parameter></paramdef>
<paramdef>unsigned <parameter>n</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int sd_bus_message_append_string_space</funcdef>
<paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
<paramdef>size_t <parameter>size</parameter></paramdef>
<paramdef>char **<parameter>s</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para>The functions
<function>sd_bus_message_append_string_memfd</function> and
<function>sd_bus_message_append_string_iovec</function> can be
used to append a single string (item of type <literal>s</literal>)
to message <parameter>m</parameter>.</para>
<para>In case of
<function>sd_bus_message_append_string_memfd</function>, the
contents of <parameter>memfd</parameter> are the string. They must
satisfy the same constraints as described for the
<literal>s</literal> type in
<citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
<para>In case of
<function>sd_bus_message_append_string_iovec</function>, the
payload of <parameter>iov</parameter> is the string. It must
satisfy the same constraints as described for the
<literal>s</literal> type in
<citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</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 spaces (ASCII 32) of length
<structname>iov_len</structname> 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_string_space</function> function appends
space for a string to message <parameter>m</parameter>. It behaves
similar to <function>sd_bus_message_append_basic</function> with
type <literal>s</literal>, but instead of copying a string into
the message, it returns a pointer to the destination area to
the caller in pointer <parameter>p</parameter>. Space for the string
of length <parameter>size</parameter> plus the terminating
<constant>NUL</constant> is allocated.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para>On success, those 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" />
<xi:include href="libsystemd-pkgconfig.xml" />
<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_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html">The D-Bus specification</ulink>
</para>
</refsect1>
</refentry>