1 <?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*-->
2 <!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
3 "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
6 SPDX-License-Identifier: LGPL-2.1+
8 Copyright 2014 Zbigniew Jędrzejewski-Szmek
11 <refentry id="sd_bus_message_append_string_memfd"
12 xmlns:xi="http://www.w3.org/2001/XInclude">
15 <title>sd_bus_message_append_string_memfd</title>
16 <productname>elogind</productname>
20 <contrib>A monkey with a typewriter</contrib>
21 <firstname>Zbigniew</firstname>
22 <surname>Jędrzejewski-Szmek</surname>
23 <email>zbyszek@in.waw.pl</email>
29 <refentrytitle>sd_bus_message_append_string_memfd</refentrytitle>
30 <manvolnum>3</manvolnum>
34 <refname>sd_bus_message_append_string_memfd</refname>
35 <refname>sd_bus_message_append_string_iovec</refname>
36 <refname>sd_bus_message_append_string_space</refname>
38 <refpurpose>Attach a string to a message</refpurpose>
43 <funcsynopsisinfo>#include <elogind/sd-bus.h></funcsynopsisinfo>
46 <funcdef>int sd_bus_message_append_string_memfd</funcdef>
47 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
48 <paramdef>int <parameter>memfd</parameter></paramdef>
52 <funcdef>int sd_bus_message_append_string_iovec</funcdef>
53 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
54 <paramdef>const struct iovec *<parameter>iov</parameter></paramdef>
55 <paramdef>unsigned <parameter>n</parameter></paramdef>
59 <funcdef>int sd_bus_message_append_string_space</funcdef>
60 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
61 <paramdef>size_t <parameter>size</parameter></paramdef>
62 <paramdef>char **<parameter>s</parameter></paramdef>
68 <title>Description</title>
71 <function>sd_bus_message_append_string_memfd</function> and
72 <function>sd_bus_message_append_string_iovec</function> can be
73 used to append a single string (item of type <literal>s</literal>)
74 to message <parameter>m</parameter>.</para>
77 <function>sd_bus_message_append_string_memfd</function>, the
78 contents of <parameter>memfd</parameter> are the string. They must
79 satisfy the same constraints as described for the
80 <literal>s</literal> type in
81 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
84 <function>sd_bus_message_append_string_iovec</function>, the
85 payload of <parameter>iov</parameter> is the string. It must
86 satisfy the same constraints as described for the
87 <literal>s</literal> type in
88 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
90 <para>The <parameter>iov</parameter> argument must point to
91 <parameter>n</parameter> <structname>struct iovec</structname>
92 structures. Each structure may have the
93 <structname>iov_base</structname> field set, in which case the
94 memory pointed to will be copied into the message, or unset, in
95 which case a block of spaces (ASCII 32) of length
96 <structname>iov_len</structname> will be inserted. The
97 memory pointed at by <parameter>iov</parameter> may be changed
98 after this call.</para>
101 <function>sd_bus_message_append_string_space</function> function appends
102 space for a string to message <parameter>m</parameter>. It behaves
103 similar to <function>sd_bus_message_append_basic</function> with
104 type <literal>s</literal>, but instead of copying a string into
105 the message, it returns a pointer to the destination area to
106 the caller in pointer <parameter>p</parameter>. Space for the string
107 of length <parameter>size</parameter> plus the terminating
108 <constant>NUL</constant> is allocated.</para>
112 <title>Return Value</title>
114 <para>On success, those calls return 0 or a positive integer. On
115 failure, they returns a negative errno-style error code.</para>
118 <xi:include href="sd_bus_message_append_basic.xml" xpointer="errors" />
120 <xi:include href="libelogind-pkgconfig.xml" />
123 <title>See Also</title>
126 <!-- 0 /// elogind is in section 8
127 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
129 <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
131 <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
132 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
133 <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html">The D-Bus specification</ulink>