-<?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">
-
-<!--
- This file is part of systemd.
-
- Copyright 2015 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/>.
--->
+<?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+ -->
<refentry id="sd_event_source_set_priority" xmlns:xi="http://www.w3.org/2001/XInclude">
<refentryinfo>
<title>sd_event_source_set_priority</title>
<productname>systemd</productname>
-
- <authorgroup>
- <author>
- <contrib>Developer</contrib>
- <firstname>Lennart</firstname>
- <surname>Poettering</surname>
- <email>lennart@poettering.net</email>
- </author>
- </authorgroup>
</refentryinfo>
<refmeta>
<funcsynopsisinfo>#include <systemd/sd-event.h></funcsynopsisinfo>
<funcsynopsisinfo><token>enum</token> {
- <constant>SD_EVENT_SOURCE_IMPORTANT</constant> = -100,
- <constant>SD_EVENT_SOURCE_NORMAL</constant> = 0,
- <constant>SD_EVENT_SOURCE_IDLE</constant> = 100,
+ <constant>SD_EVENT_PRIORITY_IMPORTANT</constant> = -100,
+ <constant>SD_EVENT_PRIORITY_NORMAL</constant> = 0,
+ <constant>SD_EVENT_PRIORITY_IDLE</constant> = 100,
};</funcsynopsisinfo>
<funcprototype>
<constant>SD_EVENT_PRIORITY_IDLE</constant> (100) may be used to
indicate event sources that shall be dispatched early, normally or
late. It is recommended to specify priorities based on these
- definitions, and relative to them -- however, the full 64bit
+ definitions, and relative to them — however, the full 64bit
signed integer range is available for ordering event
sources.</para>
reliable. However, it is guaranteed that if events are seen on
multiple same-priority event sources at the same time, each one is
not dispatched again until all others have been dispatched
- once. This behaviour guarantees that within each priority
+ once. This behavior guarantees that within each priority
particular event sources do not starve or dominate the event
loop.</para>
+ <para>The priority of event sources may be changed at any time of their lifetime, with the exception of inotify
+ event sources (i.e. those created with
+ <citerefentry><refentrytitle>sd_event_add_inotify</refentrytitle><manvolnum>3</manvolnum></citerefentry>) whose
+ priority may only be changed in the time between their initial creation and the first subsequent event loop
+ iteration.</para>
+
<para><function>sd_event_source_get_priority()</function> may be
used to query the current priority assigned to the event source
object <parameter>source</parameter>.</para>
<refsect1>
<title>Return Value</title>
- <para>On success,
- <function>sd_event_source_set_priority()</function> and
- <function>sd_event_source_get_priority()</function> return a
- non-negative integer. On failure, they return a negative
- errno-style error code.</para>
- </refsect1>
+ <para>On success, <function>sd_event_source_set_priority()</function> and
+ <function>sd_event_source_get_priority()</function> return a non-negative integer. On failure, they
+ return a negative errno-style error code.</para>
- <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>-EINVAL</constant></term>
+ <variablelist>
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
- <listitem><para><parameter>source</parameter> is not a valid
- pointer to an <structname>sd_event_source</structname>
- object.</para></listitem>
- </varlistentry>
+ <listitem><para><parameter>source</parameter> is not a valid pointer to an
+ <structname>sd_event_source</structname> object.</para></listitem>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ENOMEM</constant></term>
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
- <listitem><para>Not enough memory.</para></listitem>
- </varlistentry>
+
<listitem><para>Not enough memory.</para></listitem>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ESTALE</constant></term>
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
- <listitem><para>The event loop is already terminated.</para></listitem>
+
<listitem><para>The event loop is already terminated.</para></listitem>
- </varlistentry>
+ </varlistentry>
- <varlistentry>
- <term><constant>-ECHILD</constant></term>
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
- <listitem><para>The event loop has been created in a different process.</para></listitem>
+
<listitem><para>The event loop has been created in a different process.</para></listitem>
- </varlistentry>
+ </varlistentry>
- </variablelist>
+ </variablelist>
+ </refsect2>
</refsect1>
<xi:include href="libsystemd-pkgconfig.xml" />
<citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_inotify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
<citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>
</para>
</refsect1>
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