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diff --git a/man/sd_bus_slot_set_floating.xml b/man/sd_bus_slot_set_floating.xml new file mode 100644 index 0000000..df2cbc6 --- /dev/null +++ b/man/sd_bus_slot_set_floating.xml @@ -0,0 +1,123 @@ +<?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 <systemd/sd-bus.h></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> |