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 This file is part of systemd.
10 Copyright 2014 Zbigniew Jędrzejewski-Szmek
13 <refentry id=
"sd_bus_message_append_string_memfd"
14 xmlns:
xi=
"http://www.w3.org/2001/XInclude">
17 <title>sd_bus_message_append_string_memfd
</title>
18 <productname>systemd
</productname>
22 <contrib>A monkey with a typewriter
</contrib>
23 <firstname>Zbigniew
</firstname>
24 <surname>Jędrzejewski-Szmek
</surname>
25 <email>zbyszek@in.waw.pl
</email>
31 <refentrytitle>sd_bus_message_append_string_memfd
</refentrytitle>
32 <manvolnum>3</manvolnum>
36 <refname>sd_bus_message_append_string_memfd
</refname>
37 <refname>sd_bus_message_append_string_iovec
</refname>
38 <refname>sd_bus_message_append_string_space
</refname>
40 <refpurpose>Attach a string to a message
</refpurpose>
45 <funcsynopsisinfo>#include
<systemd/sd-bus.h
></funcsynopsisinfo>
48 <funcdef>int sd_bus_message_append_string_memfd
</funcdef>
49 <paramdef>sd_bus_message *
<parameter>m
</parameter></paramdef>
50 <paramdef>int
<parameter>memfd
</parameter></paramdef>
54 <funcdef>int sd_bus_message_append_string_iovec
</funcdef>
55 <paramdef>sd_bus_message *
<parameter>m
</parameter></paramdef>
56 <paramdef>const struct iovec *
<parameter>iov
</parameter></paramdef>
57 <paramdef>unsigned
<parameter>n
</parameter></paramdef>
61 <funcdef>int sd_bus_message_append_string_space
</funcdef>
62 <paramdef>sd_bus_message *
<parameter>m
</parameter></paramdef>
63 <paramdef>size_t
<parameter>size
</parameter></paramdef>
64 <paramdef>char **
<parameter>s
</parameter></paramdef>
70 <title>Description
</title>
73 <function>sd_bus_message_append_string_memfd
</function> and
74 <function>sd_bus_message_append_string_iovec
</function> can be
75 used to append a single string (item of type
<literal>s
</literal>)
76 to message
<parameter>m
</parameter>.
</para>
79 <function>sd_bus_message_append_string_memfd
</function>, the
80 contents of
<parameter>memfd
</parameter> are the string. They must
81 satisfy the same constraints as described for the
82 <literal>s
</literal> type in
83 <citerefentry><refentrytitle>sd_bus_message_append_basic
</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
</para>
86 <function>sd_bus_message_append_string_iovec
</function>, the
87 payload of
<parameter>iov
</parameter> is the string. It must
88 satisfy the same constraints as described for the
89 <literal>s
</literal> type in
90 <citerefentry><refentrytitle>sd_bus_message_append_basic
</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
</para>
92 <para>The
<parameter>iov
</parameter> argument must point to
93 <parameter>n
</parameter> <structname>struct iovec
</structname>
94 structures. Each structure may have the
95 <structname>iov_base
</structname> field set, in which case the
96 memory pointed to will be copied into the message, or unset, in
97 which case a block of spaces (ASCII
32) of length
98 <structname>iov_len
</structname> will be inserted. The
99 memory pointed at by
<parameter>iov
</parameter> may be changed
100 after this call.
</para>
103 <function>sd_bus_message_append_string_space
</function> function appends
104 space for a string to message
<parameter>m
</parameter>. It behaves
105 similar to
<function>sd_bus_message_append_basic
</function> with
106 type
<literal>s
</literal>, but instead of copying a string into
107 the message, it returns a pointer to the destination area to
108 the caller in pointer
<parameter>p
</parameter>. Space for the string
109 of length
<parameter>size
</parameter> plus the terminating
110 <constant>NUL
</constant> is allocated.
</para>
114 <title>Return Value
</title>
116 <para>On success, those calls return
0 or a positive integer. On
117 failure, they returns a negative errno-style error code.
</para>
120 <xi:include href=
"sd_bus_message_append_basic.xml" xpointer=
"errors" />
122 <xi:include href=
"libsystemd-pkgconfig.xml" />
125 <title>See Also
</title>
128 <citerefentry><refentrytitle>systemd
</refentrytitle><manvolnum>1</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>