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diff --git a/man/sd_bus_message_append.xml b/man/sd_bus_message_append.xml new file mode 100644 index 0000000000..2a1e95aa35 --- /dev/null +++ b/man/sd_bus_message_append.xml @@ -0,0 +1,254 @@ +<?xml version='1.0'?> <!--*-nxml-*--> +<!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 +WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +Lesser General Public License for more details. + +You should have received a copy of the GNU Lesser General Public License +along with systemd; If not, see <http://www.gnu.org/licenses/>. +--> + +<refentry id="sd_bus_message_append" conditional="ENABLE_KDBUS" + xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_message_append</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</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_message_append</refname> + + <refpurpose>Attach parts of message based on a format string</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int sd_bus_message_append</funcdef> + <paramdef>sd_bus_message *<parameter>m</parameter></paramdef> + <paramdef>const char *<parameter>types</parameter></paramdef> + <paramdef>...</paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para>Function <function>sd_bus_message_append</function> appends + a sequence of items to message <parameter>m</parameter>. The + format string <parameter>types</parameter> describes the types of + arguments that follow.</para> + + <para>The format string is composed of the elements shown in the + table below. It contains zero or more single "complete types". + Each complete type may be one of the basic types or a fully + described container type. A container type may be a structure, a + variant type code, an array with its element type, or a dictionary + with its entry type. The format string is + <constant>NUL</constant>-terminated.</para> + + <para>In case of a basic type, one argument of the corresponding + type is expected.</para> + + <para>A structure is denoted by a sequence of complete types + between <literal>(</literal> and <literal>)</literal>. This + sequence cannot be empty — it must contain at least one type. + Arguments corresponding to this nested sequence follow the same + rules as if they were not nested.</para> + + <para>A variant is denoted by <literal>v</literal>. Correspoding + arguments must include a format string denoting a complete type, + and following that, arguments corresponding to the specified type. + </para> + + <para>An array is denoted by <literal>a</literal> followed by a + complete type. Corresponding arguments must include the size of + the array, and then repeated this number of times, arguments + corresponding to the nested type.</para> + + <para>A dictionary is an array of dictionary entries, denoted by + <literal>a</literal> followed by a pair of complete types between + <literal>{</literal> and <literal>}</literal>. The first of those + types must be a basic type. Corresponding arguments must include + the size of the dictionary, and then repeated this number of + times, arguments corresponding to each of the two nested + types.</para> + + <table> + <title>Item format specifiers</title> + + <tgroup cols='4'> + <xi:include href="sd_bus_message_append_basic.xml" xpointer="xpointer(//table[@id='format-specifiers'])//colspec" /> + <xi:include href="sd_bus_message_append_basic.xml" xpointer="xpointer(//table[@id='format-specifiers']//thead)" /> + + <tbody> + <xi:include href="sd_bus_message_append_basic.xml" xpointer="xpointer(//table[@id='format-specifiers']//tbody/*)" /> + + <row> + <entry><literal>a</literal></entry> + <entry><constant>SD_BUS_TYPE_ARRAY</constant></entry> + <entry>array</entry> + <entry>determined by array type and size</entry> + </row> + + <row> + <entry><literal>v</literal></entry> + <entry><constant>SD_BUS_TYPE_VARIANT</constant></entry> + <entry>variant</entry> + <entry>determined by the type argument</entry> + </row> + + <row> + <entry><literal>(</literal></entry> + <entry><constant>SD_BUS_TYPE_STRUCT_BEGIN</constant></entry> + <entry>array start</entry> + <entry morerows="1">determined by the nested types</entry> + </row> + <row> + <entry><literal>)</literal></entry> + <entry><constant>SD_BUS_TYPE_STRUCT_END</constant></entry> + <entry>array end</entry> + </row> + + <row> + <entry><literal>{</literal></entry> + <entry><constant>SD_BUS_TYPE_DICT_ENTRY_BEGIN</constant></entry> + <entry>dictionary entry start</entry> + <entry morerows="1">determined by the nested types</entry> + </row> + <row> + <entry><literal>}</literal></entry> + <entry><constant>SD_BUS_TYPE_DICT_ENTRY_END</constant></entry> + <entry>dictionary entry end</entry> + </row> + </tbody> + </tgroup> + </table> + </refsect1> + + <refsect1> + <title>Types string grammar</title> + + <programlisting>types ::= complete_type* +complete_type ::= basic_type | variant | structure | array | dictionary +basic_type ::= "y" | "n" | "q" | "u" | "i" | "x" | "t" | "d" | + "b" | "h" | + "s" | "o" | "g" +variant ::= "v" +structure ::= "(" complete_type+ ")" +array ::= "a" complete_type +dictionary ::= "a" "{" basic_type complete_type "}" +</programlisting> + </refsect1> + + <refsect1> + <title>Examples</title> + + <para>Append a single basic type (the string <literal>a string</literal>): + </para> + + <programlisting>sd_bus_message *m; +... +sd_bus_message_append(m, "s", "a string");</programlisting> + + <para>Append all types of integers:</para> + + <programlisting>uint8_t y = 1; +int16_t n = 2; +uint16_t q = 3; +int32_t i = 4; +uint32_t u = 5; +int32_t x = 6; +uint32_t t = 7; +double d = 8.0; +sd_bus_message_append(m, "ynqiuxtd", y, n, q, i, u, x, t, d);</programlisting> + + <para>Append a structure composed of string and a D-Bus path:</para> + + <programlisting>sd_bus_message_append(m, "(so)", "a string", "/a/path"); +</programlisting> + + <para>Append an array of UNIX file descriptors:</para> + + <programlisting>sd_bus_message_append(m, "ah", 3, STDIN_FILENO, STDOUT_FILENO, STDERR_FILENO); +</programlisting> + + <para>Append a variant, with the real type "g" (signature), + and value "sdbusisgood":</para> + + <programlisting>sd_bus_message_append(m, "v", "g", "sdbusisgood");</programlisting> + + <para>Append a dictionary containing the mapping {1=>"a", 2=>"b", 3=>""}: + </para> + + <programlisting>sd_bus_message_append(m, "a{is}", 3, 1, "a", 2, "b", 3, NULL); + </programlisting> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>On success, this call returns 0 or a positive + integer. On failure, this call 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_open_user()</function> and other functions + described here are available as a shared library, which can be + compiled and linked to with the + <constant>libsystemd-bus</constant> <citerefentry><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_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_ref</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>ssh</refentrytitle><manvolnum>1</manvolnum></citerefentry>, + <citerefentry><refentrytitle>systemd-machined.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>, + <citerefentry><refentrytitle>machinectl</refentrytitle><manvolnum>1</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |