-<?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">
+<?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+ -->
-<!--
- This file is part of systemd.
-
- Copyright 2014 Lennart Poettering
-
- 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_negotiate_fds">
+<refentry id="sd_bus_negotiate_fds" xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_bus_negotiate_fds</title>
<productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
</refentryinfo>
<refmeta>
<refnamediv>
<refname>sd_bus_negotiate_fds</refname>
- <refname>sd_bus_negotiate_timestamps</refname>
+ <refname>sd_bus_negotiate_timestamp</refname>
<refname>sd_bus_negotiate_creds</refname>
<refpurpose>Control feature negotiation on bus connections</refpurpose>
default, file descriptor passing is negotiated for all
connections.</para>
- <para>Note that when bus activation is used, it is highly
- recommended to set the <option>AcceptFileDescriptors=</option>
- setting in the <filename>.busname</filename> unit file to the same
- setting as negotiated by the program ultimately activated. By
- default, file descriptor passing is enabled for both.</para>
-
- <para><function>sd_bus_negotiate_timestamps()</function> controls
- whether implicit sender timestamps shall be attached automatically
- to all incoming messages. Takes a bus object and a boolean, which,
- when true, enables timestamping, and, when false, disables it.
- Use
+ <para><function>sd_bus_negotiate_timestamp()</function> controls whether implicit sender
+ timestamps shall be attached automatically to all incoming messages. Takes a bus object and a
+ boolean, which, when true, enables timestamping, and, when false, disables it. Use
<citerefentry><refentrytitle>sd_bus_message_get_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_seqnum</refentrytitle><manvolnum>3</manvolnum></citerefentry>
- to query the timestamps of incoming messages. If negotiation is
- disabled or not supported these calls will fail with
- <constant>-ENODATA</constant>. Note that not all transports
- support timestamping of messages. Specifically, timestamping is
- only available on the kdbus transport, but not on dbus1. The
- timestamping is applied by the kernel and cannot be manipulated by
- userspace. By default, message timestamping is not negotiated for
+ to query the timestamps of incoming messages. If negotiation is disabled or not supported, these
+ calls will fail with <constant>-ENODATA</constant>. Note that currently no transports support
+ timestamping of messages. By default, message timestamping is not negotiated for
connections.</para>
- <para><function>sd_bus_negotiate_creds()</function> controls
- whether and which implicit sender credentials shall be attached
- automatically to all incoming messages. Takes a bus object, a
- boolean indicating whether to enable or disable the credential
- parts encoded in the bit mask value argument. Note that not all
- transports support attaching sender credentials to messages, or do
- not support all types of sender credential parameters, or might
- suppress them under certain circumstances for individual
- messages. Specifically, implicit sender credentials on messages
- are only fully supported on kdbus transports, and dbus1 only
- supports <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>. The sender
- credentials are attached by the kernel and cannot be manipulated
- by userspace, and are thus suitable for authorization
- decisions. By default, only
- <constant>SD_BUS_CREDS_WELL_KNOWN_NAMES</constant> and
- <constant>SD_BUS_CREDS_UNIQUE_NAME</constant> are enabled. In
- fact, these two credential fields are always sent along and cannot
- be turned off.</para>
+ <para><function>sd_bus_negotiate_creds()</function> controls whether and which implicit sender
+ credentials shall be attached automatically to all incoming messages. Takes a bus object and a
+ boolean indicating whether to enable or disable the credential parts encoded in the bit mask
+ value argument. Note that not all transports support attaching sender credentials to messages,
+ or do not support all types of sender credential parameters, or might suppress them under
+ certain circumstances for individual messages. Specifically, dbus1 only supports
+ <constant>SD_BUS_CREDS_UNIQUE_NAME</constant>. The sender credentials are suitable for
+ authorization decisions. By default, only <constant>SD_BUS_CREDS_WELL_KNOWN_NAMES</constant> and
+ <constant>SD_BUS_CREDS_UNIQUE_NAME</constant> are enabled. In fact, these two credential fields
+ are always sent along and cannot be turned off.</para>
<para>The <function>sd_bus_negotiate_fds()</function> function may
be called only before the connection has been started with
<citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Both
<function>sd_bus_negotiate_timestamp()</function> and
<function>sd_bus_negotiate_creds()</function> may also be called
- after a connection has been set up. Note that when operating on a
+ after a connection has been set up. Note that, when operating on a
connection that is shared between multiple components of the same
program (for example via
- <citerefentry><refentrytitle>sd_bus_default</refentrytitle><manvolnum>3</manvolnum></citerefentry>)
+ <citerefentry><refentrytitle>sd_bus_default</refentrytitle><manvolnum>3</manvolnum></citerefentry>),
it is highly recommended to only enable additional per message
metadata fields, but never disable them again, in order not to
disable functionality needed by other components.</para>
<refsect1>
<title>Return Value</title>
- <para>On success, these functions returns 0 or a
+ <para>On success, these functions return 0 or a
positive integer. On failure, they return a negative errno-style
error code.</para>
- </refsect1>
- <refsect1>
- <title>Errors</title>
+ <refsect2>
+ <title>Errors</title>
- <para>Returned errors may indicate the following problems:</para>
+
<para>Returned errors may indicate the following problems:</para>
- <variablelist>
- <varlistentry>
- <term><constant>-EPERM</constant></term>
+ <variablelist>
+ <varlistentry>
+ <term><constant>-EPERM</constant></term>
- <listitem><para>The bus connection has already been started.</para></listitem>
- </varlistentry>
- </variablelist>
+ <listitem><para>The bus connection has already been started.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
</refsect1>
- <refsect1>
- <title>Notes</title>
-
- <para><function>sd_bus_negotiate_fds()</function> and the other
- functions described here are available as a shared library, which
- can be compiled and linked to with the
- <constant>libsystemd</constant> <citerefentry project='die-net'><refentrytitle>pkg-config</refentrytitle><manvolnum>1</manvolnum></citerefentry>
- file.</para>
- </refsect1>
+ <xi:include href="libsystemd-pkgconfig.xml" />
<refsect1>
<title>See Also</title>
<citerefentry><refentrytitle>sd_bus_message_get_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_realtime_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_seqnum</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>systemd.busname</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>
projects / thirdparty / systemd.git / blobdiff