systemd/man/systemd-stdio-bridge.xml
Lennart Poettering a2012854f5 man: systemd-stdio-bridge doesn't connect "two busses"
In D-Bus, clients connect to a bus (the usual case), or use direct
questions to each other (the unusual case). A bus is a program one can
connect to and implemented by dbus-daemon or dbus-broker. HOwever,
busses never connect between each other, that doesn't exist. Hence don't
claim so.

This is probably confusion about the fact that sd-bus calls D-Bus
connection objects just "sd_bus" for simplicity, given they are used in
99% of the cases to connect to a bus — only in exceptional cases they
are used for direct connections between peers without involving a bus.

Follow-up for b7bb58ef70
2022-02-04 17:43:44 +00:00

92 lines
3.6 KiB
XML

<?xml version='1.0'?> <!--*-nxml-*-->
<!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 -->
<refentry id="systemd-stdio-bridge"
xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>systemd-stdio-bridge</title>
<productname>systemd</productname>
</refentryinfo>
<refmeta>
<refentrytitle>systemd-stdio-bridge</refentrytitle>
<manvolnum>1</manvolnum>
</refmeta>
<refnamediv>
<refname>systemd-stdio-bridge</refname>
<refpurpose>D-Bus proxy</refpurpose>
</refnamediv>
<refsynopsisdiv>
<cmdsynopsis>
<command>systemd-stdio-bridge</command>
<arg choice="opt" rep="repeat">OPTIONS</arg>
</cmdsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><command>systemd-stdio-bridge</command> implements a proxy between STDIN/STDOUT and a D-Bus bus. It
expects to receive an open connection via STDIN/STDOUT when started, and will create a new connection to
the specified bus. It will then forward messages between the two connections. This program is suitable
for socket activation: the first connection may be a pipe or a socket and must be passed as either
standard input, or as an open file descriptor according to the protocol described in
<citerefentry><refentrytitle>sd_listen_fds</refentrytitle><manvolnum>3</manvolnum></citerefentry>. The
second connection will be made by default to the local system bus, but this can be influenced by the
<option>--user</option>, <option>--system</option>, <option>--machine=</option>, and
<option>--bus-path=</option> options described below.</para>
<para><citerefentry><refentrytitle>sd-bus</refentrytitle><manvolnum>3</manvolnum></citerefentry> uses
<command>systemd-stdio-bridge</command> to forward D-Bus connections over
<citerefentry project='die-net'><refentrytitle>ssh</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
or to connect to the bus of a different user, see
<citerefentry><refentrytitle>sd_bus_set_address</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
</para>
</refsect1>
<refsect1>
<title>Options</title>
<para>The following options are understood:</para>
<variablelist>
<xi:include href="user-system-options.xml" xpointer="user" />
<xi:include href="user-system-options.xml" xpointer="system" />
<xi:include href="user-system-options.xml" xpointer="machine" />
<varlistentry>
<term><option>-p <replaceable>PATH</replaceable></option></term>
<term><option>--bus-path=<replaceable>PATH</replaceable></option></term>
<listitem><para>Path to the bus address. Default: <literal>unix:path=/run/dbus/system_bus_socket</literal>
</para></listitem>
</varlistentry>
<xi:include href="standard-options.xml" xpointer="help" />
<xi:include href="standard-options.xml" xpointer="version" />
</variablelist>
</refsect1>
<refsect1>
<title>Exit status</title>
<para>On success, 0 is returned, a non-zero failure code otherwise.</para>
</refsect1>
<refsect1>
<title>See Also</title>
<para>
<citerefentry project='dbus'><refentrytitle>dbus-daemon</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<citerefentry project='dbus'><refentrytitle>dbus-broker</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
<ulink url="https://www.freedesktop.org/wiki/Software/dbus">D-Bus</ulink>,
<citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>