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+
9 <refentry id="sd_bus_message_append_string_memfd"
10 xmlns:xi="http://www.w3.org/2001/XInclude">
13 <title>sd_bus_message_append_string_memfd</title>
14 <productname>elogind</productname>
18 <contrib>A monkey with a typewriter</contrib>
19 <firstname>Zbigniew</firstname>
20 <surname>Jędrzejewski-Szmek</surname>
21 <email>zbyszek@in.waw.pl</email>
27 <refentrytitle>sd_bus_message_append_string_memfd</refentrytitle>
28 <manvolnum>3</manvolnum>
32 <refname>sd_bus_message_append_string_memfd</refname>
33 <refname>sd_bus_message_append_string_iovec</refname>
34 <refname>sd_bus_message_append_string_space</refname>
36 <refpurpose>Attach a string to a message</refpurpose>
41 <funcsynopsisinfo>#include <elogind/sd-bus.h></funcsynopsisinfo>
44 <funcdef>int sd_bus_message_append_string_memfd</funcdef>
45 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
46 <paramdef>int <parameter>memfd</parameter></paramdef>
50 <funcdef>int sd_bus_message_append_string_iovec</funcdef>
51 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
52 <paramdef>const struct iovec *<parameter>iov</parameter></paramdef>
53 <paramdef>unsigned <parameter>n</parameter></paramdef>
57 <funcdef>int sd_bus_message_append_string_space</funcdef>
58 <paramdef>sd_bus_message *<parameter>m</parameter></paramdef>
59 <paramdef>size_t <parameter>size</parameter></paramdef>
60 <paramdef>char **<parameter>s</parameter></paramdef>
66 <title>Description</title>
69 <function>sd_bus_message_append_string_memfd</function> and
70 <function>sd_bus_message_append_string_iovec</function> can be
71 used to append a single string (item of type <literal>s</literal>)
72 to message <parameter>m</parameter>.</para>
75 <function>sd_bus_message_append_string_memfd</function>, the
76 contents of <parameter>memfd</parameter> are the string. They must
77 satisfy the same constraints as described for the
78 <literal>s</literal> type in
79 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
82 <function>sd_bus_message_append_string_iovec</function>, the
83 payload of <parameter>iov</parameter> is the string. It must
84 satisfy the same constraints as described for the
85 <literal>s</literal> type in
86 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
88 <para>The <parameter>iov</parameter> argument must point to
89 <parameter>n</parameter> <structname>struct iovec</structname>
90 structures. Each structure may have the
91 <structname>iov_base</structname> field set, in which case the
92 memory pointed to will be copied into the message, or unset, in
93 which case a block of spaces (ASCII 32) of length
94 <structname>iov_len</structname> will be inserted. The
95 memory pointed at by <parameter>iov</parameter> may be changed
96 after this call.</para>
99 <function>sd_bus_message_append_string_space</function> function appends
100 space for a string to message <parameter>m</parameter>. It behaves
101 similar to <function>sd_bus_message_append_basic</function> with
102 type <literal>s</literal>, but instead of copying a string into
103 the message, it returns a pointer to the destination area to
104 the caller in pointer <parameter>p</parameter>. Space for the string
105 of length <parameter>size</parameter> plus the terminating
106 <constant>NUL</constant> is allocated.</para>
110 <title>Return Value</title>
112 <para>On success, those calls return 0 or a positive integer. On
113 failure, they returns a negative errno-style error code.</para>
116 <xi:include href="sd_bus_message_append_basic.xml" xpointer="errors" />
118 <xi:include href="libelogind-pkgconfig.xml" />
121 <title>See Also</title>
124 <!-- 0 /// elogind is in section 8
125 <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
127 <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
129 <citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
130 <citerefentry><refentrytitle>sd_bus_message_append_basic</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
131 <ulink url="http://dbus.freedesktop.org/doc/dbus-specification.html">The D-Bus specification</ulink>