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+<?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 -->
+
+<refentry id="sd_bus_slot_set_floating" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_bus_slot_set_floating</title>
+ <productname>systemd</productname>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_bus_slot_set_floating</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_bus_slot_set_floating</refname>
+ <refname>sd_bus_slot_get_floating</refname>
+
+ <refpurpose>Control whether a bus slot object is "floating"</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include &lt;systemd/sd-bus.h&gt;</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_bus_slot_set_floating</function></funcdef>
+ <paramdef>sd_bus_slot *<parameter>slot</parameter></paramdef>
+ <paramdef>int <parameter>b</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_bus_slot_get_floating</function></funcdef>
+ <paramdef>sd_bus_slot *<parameter>slot</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_bus_slot_set_floating()</function> controls whether the specified bus slot object
+ <parameter>slot</parameter> shall be "floating" or not. A floating bus slot object's lifetime is bound to the
+ lifetime of the bus object it is associated with, meaning that it remains allocated as long as the bus object
+ itself and is freed automatically when the bus object is freed. Regular (i.e. non-floating) bus slot objects keep
+ the bus referenced, hence the bus object remains allocated at least as long as there remains at least one
+ referenced bus slot object around. The floating state hence controls the direction of referencing between the bus
+ object and the bus slot objects: if floating the bus pins the bus slot, and otherwise the bus slot pins the bus
+ objects. Use <function>sd_bus_slot_set_floating()</function> to switch between both modes: if the
+ <parameter>b</parameter> parameter is zero, the slot object is considered floating, otherwise it is made a regular
+ (non-floating) slot object.</para>
+
+ <para>Bus slot objects may be allocated with calls such as
+ <citerefentry><refentrytitle>sd_bus_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>. If the
+ <parameter>slot</parameter> of these functions is non-<constant>NULL</constant> the slot object will be of the
+ regular kind (i.e. non-floating), otherwise it will be created floating. With
+ <function>sd_bus_slot_set_floating()</function> a bus slot object allocated as regular can be converted into a
+ floating object and back. This is particularly useful for creating a bus slot object, then changing parameters of
+ it, and then turning it into a floating object, whose lifecycle is managed by the bus object.</para>
+
+ <para><function>sd_bus_slot_get_floating()</function> returns the current floating state of the specified bus slot
+ object. It returns negative on error, zero if the bus slot object is a regular (non-floating) object and positive
+ otherwise.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, these functions return 0 or a positive integer. On failure, they return a negative
+ errno-style error code.</para>
+
+ <refsect2>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>The <parameter>slot</parameter> parameter is <constant>NULL</constant>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The bus connection has been created in a different process, library or module instance.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The bus object the specified bus slot object is associated with has already been
+ freed, and hence no change in the floating state can be made anymore.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect2>
+ </refsect1>
+
+ <xi:include href="libsystemd-pkgconfig.xml" />
+
+ <refsect1>
+ <title>History</title>
+ <para><function>sd_bus_slot_set_floating()</function> and
+ <function>sd_bus_slot_get_floating()</function> were added in version 239.</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_slot_set_destroy_callback</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_bus_add_match</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>