<?xml version='1.0'?> <!--*- Mode: nxml; nxml-child-indent: 2; indent-tabs-mode: nil -*--> <!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 2016 Julian Orth 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_process"> <refentryinfo> <title>sd_bus_process</title> <productname>systemd</productname> <authorgroup> <author> <firstname>Julian</firstname> <surname>Orth</surname> <email>ju.orth@gmail.com</email> </author> </authorgroup> </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>r</parameter></paramdef> </funcprototype> </funcsynopsis> </refsynopsisdiv> <refsect1> <title>Description</title> <para> <function>sd_bus_process()</function> drives the connection between the message bus and the client. That is, it handles connecting, authentication, and message processing. It should be called in a loop until no further progress can be made or an error occurs. </para> <para> Once no further progress can be made, <citerefentry><refentrytitle>sd_bus_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry> should be called. Alternatively the user can wait for incoming data on the file descriptor returned by <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>r</parameter> is not NULL and the call processed a message, <code>*r</code> 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>r</parameter> is not NULL, progress was made, but no message was processed, <code>*r</code> is set to NULL. </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 errno-style error code is returned. </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>, </para> </refsect1> </refentry>