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diff --git a/man/sd_bus_process.xml b/man/sd_bus_process.xml new file mode 100644 index 0000000..193c16c --- /dev/null +++ b/man/sd_bus_process.xml @@ -0,0 +1,133 @@ +<?xml version='1.0'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd"> + +<!-- + SPDX-License-Identifier: LGPL-2.1-or-later + + Copyright © 2016 Julian Orth +--> + +<refentry id="sd_bus_process" xmlns:xi="http://www.w3.org/2001/XInclude"> + + <refentryinfo> + <title>sd_bus_process</title> + <productname>systemd</productname> + </refentryinfo> + + <refmeta> + <refentrytitle>sd_bus_process</refentrytitle> + <manvolnum>3</manvolnum> + </refmeta> + + <refnamediv> + <refname>sd_bus_process</refname> + + <refpurpose>Drive the connection</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcsynopsisinfo>#include <systemd/sd-bus.h></funcsynopsisinfo> + + <funcprototype> + <funcdef>int <function>sd_bus_process</function></funcdef> + <paramdef>sd_bus *<parameter>bus</parameter></paramdef> + <paramdef>sd_bus_message **<parameter>ret</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Description</title> + + <para><function>sd_bus_process()</function> drives the connection between the client and the message bus. That is, + it handles connecting, authentication, and message processing. When invoked pending I/O work is executed, and + queued incoming messages are dispatched to registered callbacks. Each time it is invoked a single operation is + executed. It returns zero when no operations were pending and positive if a message was processed. When zero is + returned the caller should synchronously poll for I/O events before calling into + <function>sd_bus_process()</function> again. For that either use the simple, synchronous + <citerefentry><refentrytitle>sd_bus_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry> call, or hook up + the bus connection object to an external or manual event loop using + <citerefentry><refentrytitle>sd_bus_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>. + </para> + + <para><function>sd_bus_process()</function> processes at most one incoming message per call. If the parameter + <parameter>ret</parameter> is not <constant>NULL</constant> and the call processed a message, + <parameter>*ret</parameter> is set to this message. The caller owns a reference to this message and should call + <citerefentry><refentrytitle>sd_bus_message_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry> when the + message is no longer needed. If <parameter>ret</parameter> is not <constant>NULL</constant>, progress was made, but no message was + processed, <parameter>*ret</parameter> is set to <constant>NULL</constant>.</para> + + <para>If the bus object is connected to an + <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry> event loop (with + <citerefentry><refentrytitle>sd_bus_attach_event</refentrytitle><manvolnum>3</manvolnum></citerefentry>), it is not + necessary to call <function>sd_bus_process()</function> directly as it is invoked automatically when + necessary.</para> + </refsect1> + + <refsect1> + <title>Return Value</title> + + <para>If progress was made, a positive integer is returned. If no progress was made, 0 is returned. If an + error occurs, a negative <varname>errno</varname>-style error code is returned.</para> + + <refsect2> + <title>Errors</title> + + <para>Returned errors may indicate the following problems:</para> + + <variablelist> + <varlistentry> + <term><constant>-EINVAL</constant></term> + + <listitem><para>An invalid bus object was passed.</para></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-ECHILD</constant></term> + + <listitem><para>The bus connection was allocated in a parent process and is being reused in a child + process after <function>fork()</function>.</para></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-ENOTCONN</constant></term> + + <listitem><para>The bus connection has been terminated already.</para></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-ECONNRESET</constant></term> + + <listitem><para>The bus connection has been terminated just now.</para></listitem> + </varlistentry> + + <varlistentry> + <term><constant>-EBUSY</constant></term> + + <listitem><para>This function is already being called, i.e. <function>sd_bus_process()</function> + has been called from a callback function that itself was called by + <function>sd_bus_process()</function>.</para></listitem> + </varlistentry> + </variablelist> + </refsect2> + </refsect1> + + <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_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_message_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>, + <citerefentry><refentrytitle>sd_bus_attach_event</refentrytitle><manvolnum>3</manvolnum></citerefentry> + </para> + </refsect1> + +</refentry> |