1
0
mirror of https://github.com/systemd/systemd.git synced 2024-11-14 15:21:37 +03:00
systemd/man/sd_bus_negotiate_fds.xml
Zbigniew Jędrzejewski-Szmek 5aded36978 man: add a mapping for external manpages
It is annoying when we have dead links on fd.o.

Add project='man-pages|die-net|archlinux' to <citerefentry>-ies.

In generated html, add external links to
http://man7.org/linux/man-pages/man, http://linux.die.net/man/,
https://www.archlinux.org/.

By default, pages in sections 2 and 4 go to man7, since Michael
Kerrisk is the autorative source on kernel related stuff.

The rest of links goes to linux.die.net, because they have the
manpages.

Except for the pacman stuff, since it seems to be only available from
archlinux.org.

Poor gummiboot gets no link, because gummitboot(8) ain't to be found
on the net. According to common wisdom, that would mean that it does
not exist. But I have seen Kay using it, so I know it does, and
deserves to be found. Can somebody be nice and put it up somewhere?
2014-07-07 18:36:55 -04:00

177 lines
7.2 KiB
XML
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<?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 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" conditional="ENABLE_KDBUS">
<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>
<refentrytitle>sd_bus_negotiate_fds</refentrytitle>
<manvolnum>3</manvolnum>
</refmeta>
<refnamediv>
<refname>sd_bus_negotiate_fds</refname>
<refname>sd_bus_negotiate_timestamps</refname>
<refname>sd_bus_negotiate_creds</refname>
<refpurpose>Control feature negotiation on bus connections</refpurpose>
</refnamediv>
<refsynopsisdiv>
<funcsynopsis>
<funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
<funcprototype>
<funcdef>int <function>sd_bus_negotiate_fds</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>int <parameter>b</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_bus_negotiate_timestamp</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>int <parameter>b</parameter></paramdef>
</funcprototype>
<funcprototype>
<funcdef>int <function>sd_bus_negotiate_creds</function></funcdef>
<paramdef>sd_bus *<parameter>bus</parameter></paramdef>
<paramdef>int <parameter>b</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Description</title>
<para><function>sd_bus_negotiate_fds()</function> controls whether
file descriptor passing shall be negotiated for the specified bus
connection. It takes a bus object and a boolean, which, when true,
enables file descriptor passing, and, when false, disables it. Note
that not all transports and servers support file descriptor
passing. To find out whether file descriptor passing is available
after negotiation, use
<citerefentry><refentrytitle>sd_bus_can_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>
and pass <constant>SD_BUS_TYPE_UNIX_FD</constant>. Note that file
descriptor passing is always enabled for both sending and
receiving or for neither, but never only in one direction. By
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. If
this is disabled,
<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_seqno</refentrytitle><manvolnum>3</manvolnum></citerefentry>
fail with <constant>-ENODATA</constant> on incoming messages. Note
that not all transports support timestamping of messages. On local
transports, the timestamping is applied by the kernel and cannot be
manipulated by userspace.</para>
<para><function>sd_bus_negotiate_creds()</function> controls
whether implicit sender credentials shall be attached
automatically to all incoming messages. Takes a bus object and a
bit mask value, which controls which credential parameters are
attached. If this is not used,
<citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
fails with <constant>-ENODATA</constant> on incoming
messages. Note that not all transports support attaching sender
credentials to messages, or do not support all types of sender
credential parameters. On local transports, the sender credentials
are attached by the kernel and cannot be manipulated by
userspace. By default, no sender credentials are attached.</para>
<para>These functions may be called only before the connection has
been started with
<citerefentry><refentrytitle>sd_bus_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
</refsect1>
<refsect1>
<title>Return Value</title>
<para>On success, these functions returns 0 or a
positive integer. On failure, they return a negative errno-style
error code.</para>
</refsect1>
<refsect1>
<title>Errors</title>
<para>Returned errors may indicate the following problems:</para>
<variablelist>
<varlistentry>
<term><varname>-EPERM</varname></term>
<listitem><para>The bus connection has already been started.</para></listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Notes</title>
<para><function>sd_bus_negotiate_fs()</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>
<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_start</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_can_send</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_monotonic_usec</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_bus_message_get_creds</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>
</refentry>