--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd-event" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd-event</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd-event</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd-event</refname>
+ <refpurpose>A generic event loop implementation</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+ </funcsynopsis>
+
+ <cmdsynopsis>
+ <command>pkg-config --cflags --libs libelogind</command>
+ </cmdsynopsis>
+
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><filename>sd-event.h</filename> provides a generic event
+ loop implementation, based on Linux <citerefentry
+ project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>.
+ </para>
+
+ <para>See
+ <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_run</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_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_get_event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_get_pending</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_prepare</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_set_watchdog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for more information about the functions available.</para>
+
+ <para>The event loop design is targeted on running a separate
+ instance of the event loop in each thread; it has no concept of
+ distributing events from a single event loop instance onto
+ multiple worker threads. Dispatching events is strictly ordered
+ and subject to configurable priorities. In each event loop
+ iteration a single event source is dispatched. Each time an event
+ source is dispatched the kernel is polled for new events, before
+ the next event source is dispatched. The event loop is designed to
+ honour priorities and provide fairness within each priority. It is
+ not designed to provide optimal throughput, as this contradicts
+ these goals due the limitations of the underlying <citerefentry
+ project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+ primitives.</para>
+
+ <para>The event loop implementation provides the following features:</para>
+
+ <orderedlist>
+ <listitem><para>I/O event sources, based on <citerefentry
+ project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>'s
+ file descriptor watching, including edge triggered events (<constant>EPOLLET</constant>). See <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>Timer event sources, based on <citerefentry
+ project='man-pages'><refentrytitle>timerfd_create</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ supporting the <constant>CLOCK_MONOTONIC</constant>,
+ <constant>CLOCK_REALTIME</constant>,
+ <constant>CLOCK_BOOTIME</constant> clocks, as well as the
+ <constant>CLOCK_REALTIME_ALARM</constant> and
+ <constant>CLOCK_BOOTTIME_ALARM</constant> clocks that can resume
+ the system from suspend. When creating timer events a required
+ accuracy parameter may be specified which allows coalescing of
+ timer events to minimize power consumption. See <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>UNIX process signal events, based on
+ <citerefentry
+ project='man-pages'><refentrytitle>signalfd</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ including full support for real-time signals, and queued parameters. See <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>Child process state change events, based on
+ <citerefentry project='man-pages'><refentrytitle>waitid</refentrytitle><manvolnum>2</manvolnum></citerefentry>. See <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>Static event sources, of three types: defer,
+ post and exit, for invoking calls in each event loop, after
+ other event sources or at event loop termination. See
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>Event sources may be assigned a 64bit priority
+ value, that controls the order in which event sources are
+ dispatched if multiple are pending simultanously. See
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>The event loop may automatically send watchdog
+ notification messages to the service manager. See
+ <citerefentry><refentrytitle>sd_event_set_watchdog</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ <listitem><para>The event loop may be integrated into foreign
+ event loops, such as the GLib one. See
+ <citerefentry><refentrytitle>sd_event_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for an example.</para></listitem>
+ </orderedlist>
+
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_run</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_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_get_event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_get_pending</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_prepare</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_wait</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_get_fd</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_set_watchdog</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>timerfd_create</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>signalfd</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>waitid</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_add_io" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_add_io</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_add_io</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_add_io</refname>
+ <refname>sd_event_source_get_io_events</refname>
+ <refname>sd_event_source_set_io_events</refname>
+ <refname>sd_event_source_get_io_revents</refname>
+ <refname>sd_event_source_get_io_fd</refname>
+ <refname>sd_event_source_set_io_fd</refname>
+ <refname>sd_event_source</refname>
+ <refname>sd_event_io_handler_t</refname>
+
+ <refpurpose>Add an I/O event source to an event loop</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcsynopsisinfo><token>typedef</token> struct sd_event_source sd_event_source;</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>typedef int (*<function>sd_event_io_handler_t</function>)</funcdef>
+ <paramdef>sd_event_source *<parameter>s</parameter></paramdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>uint32_t <parameter>revents</parameter></paramdef>
+ <paramdef>void *<parameter>userdata</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_add_io</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>sd_event_source **<parameter>source</parameter></paramdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>uint32_t <parameter>events</parameter></paramdef>
+ <paramdef>sd_event_io_handler_t <parameter>handler</parameter></paramdef>
+ <paramdef>void *<parameter>userdata</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_io_events</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>uint32_t *<parameter>events</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_io_events</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>uint32_t <parameter>events</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_io_revents</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>uint32_t *<parameter>revents</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_io_fd</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_io_fd</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_add_io()</function> adds a new I/O event
+ source to an event loop. The event loop object is specified in the
+ <parameter>event</parameter> parameter, the event source object is
+ returned in the <parameter>source</parameter> parameter. The
+ <parameter>fd</parameter> parameter takes the UNIX file descriptor
+ to watch, which may refer to a socket, a FIFO, a message queue, a
+ serial connection, a character device or any other file descriptor
+ compatible with Linux <citerefentry
+ project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>. The
+ <parameter>events</parameter> parameter takes a bit mask of I/O
+ events to watch the file descriptor for, a combination of the
+ following event flags: <constant>EPOLLIN</constant>,
+ <constant>EPOLLOUT</constant>, <constant>EPOLLRDHUP</constant>,
+ <constant>EPOLLPRI</constant> and <constant>EPOLLET</constant>,
+ see <citerefentry
+ project='man-pages'><refentrytitle>epoll_ctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ for details. The <parameter>handler</parameter> shall reference a
+ function to call when the I/O event source is triggered. The
+ handler function will be passed the
+ <parameter>userdata</parameter> pointer, which may be chosen
+ freely by the caller. The handler will also be passed the file
+ descriptor the event was seen on as well as the actual event flags
+ seen. It's generally a subset of the events watched, however may
+ additionally have <constant>EPOLLERR</constant> and
+ <constant>EPOLLHUP</constant> set.</para>
+
+ <para>By default, the I/O event source will stay enabled
+ continously (<constant>SD_EVENT_ON</constant>), but this may be
+ changed with
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>.
+ If the handler function returns a negative error code, it will be
+ disabled after the invocation, even if the
+ <constant>SD_EVENT_ON</constant> mode was requested before. Note
+ that an I/O event source set to <constant>SD_EVENT_ON</constant> will
+ fire continously unless data is read or written to the file
+ descriptor in order to reset the mask of events seen.
+ </para>
+
+ <para>Setting the I/O event mask to watch for to 0 does not mean
+ that the event source won't be triggered anymore, as
+ <constant>EPOLLHUP</constant> and <constant>EPOLLERR</constant>
+ may be triggered even with a zero event mask. To temporarily
+ disable an I/O event source use
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ with <constant>SD_EVENT_OFF</constant> instead.</para>
+
+ <para>To destroy an event source object use
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ but note that the event source is only removed from the event loop
+ when all references to the event source are dropped. To make sure
+ an event source does not fire anymore, even when there's still a
+ reference to it kept, consider setting the event source to
+ <constant>SD_EVENT_OFF</constant> with
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+
+ <para>If the the second parameter of
+ <function>sd_event_add_io()</function> is passed as NULL no
+ reference to the event source object is returned. In this case the
+ event source is considered "floating", and will be destroyed
+ implicitly when the event loop itself is destroyed.</para>
+
+ <para>It is recommended to use
+ <function>sd_event_add_io()</function> only in conjunction with
+ file descriptors that have <constant>O_NONBLOCK</constant> set, to
+ ensure that all I/O operations from invoked handlers are properly
+ asynchronous and non-blocking. Using file descriptors without
+ <constant>O_NONBLOCK</constant> might result in unexpected
+ starving of other event sources. See <citerefentry
+ project='man-pages'><refentrytitle>fcntl</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ for details on enabling <constant>O_NONBLOCK</constant> mode.</para>
+
+ <para><function>sd_event_source_get_io_events()</function> retrieves
+ the configured I/O event mask to watch of an I/O event source created
+ previously with <function>sd_event_add_io()</function>. It takes
+ the event source object and a pointer to a variable to store the
+ event mask in.</para>
+
+ <para><function>sd_event_source_set_io_events()</function> changes the
+ configured I/O event mask to watch of an I/O event source created previously
+ with <function>sd_event_add_io()</function>. It takes the event
+ source object and the new event mask to set.</para>
+
+ <para><function>sd_event_source_get_io_events()</function>
+ retrieves the I/O event mask of currently seen but undispatched
+ events from an I/O event source created previously with
+ <function>sd_event_add_io()</function>. It takes the event source
+ object and a pointer to a variable to store the event mask
+ in. When called from a handler function on the handler's event
+ source object this will return the same mask as passed to the
+ handler's <parameter>revents</parameter> parameter. This call is
+ primarily useful to check for undispatched events of an event
+ source from the handler of an unrelated (possibly higher priority)
+ event source. Note the relation between
+ <function>sd_event_source_get_pending()</function> and
+ <function>sd_event_source_get_io_revents()</function>: both
+ functions will report non-zero results when there's an event
+ pending for the event source, but the former applies to all event
+ source types, the latter only to I/O event sources.</para>
+
+ <para><function>sd_event_source_get_io_fd()</function> retrieves
+ the UNIX file descriptor of an I/O event source created previously
+ with <function>sd_event_add_io()</function>. It takes the event
+ source object and returns the positive file descriptor in the return
+ value, or a negative error number on error (see below).</para>
+
+ <para><function>sd_event_source_set_io_fd()</function>
+ changes the UNIX file descriptor of an I/O event source created
+ previously with <function>sd_event_add_io()</function>. It takes
+ the event source object and the new file descriptor to set.</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>
+ </refsect1>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory to allocate an object.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>An invalid argument has been passed.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop is already terminated.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EDOM</constant></term>
+
+ <listitem><para>The passed event source is not an I/O event source.</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_get_pending</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>epoll_ctl</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>epoll</refentrytitle><manvolnum>7</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_exit" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_exit</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_exit</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_exit</refname>
+ <refname>sd_event_get_exit_code</refname>
+
+ <refpurpose>Ask the event loop to exit</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_exit</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>int <parameter>code</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_get_exit_code</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>int *<parameter>code</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_exit()</function> requests the event loop
+ specified in the <parameter>event</parameter> event loop object to
+ exit. The <parameter>code</parameter> parameter may be any integer
+ value and is returned as-is by
+ <citerefentry><refentrytitle>sd_event_loop</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ after the last event loop iteration. It may also be be queried
+ using <function>sd_event_get_exit_code()</function>, see
+ below. </para>
+
+ <para>When exiting is requested the event loop will stop listening
+ for and dispatching regular event sources. Instead it will proceed
+ with executing only event sources registered with
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ in the order defined by their priority. After all exit event
+ sources have been dispatched the event loop is terminated.</para>
+
+ <para>If <function>sd_event_exit()</function> is invoked a second
+ time while the event loop is still processing exit event sources,
+ the exit code stored in the event loop object is updated, but
+ otherwise no further operation is executed.</para>
+
+ <para><function>sd_event_get_exit_code()</function> may be used to
+ query the exit code passed into
+ <function>sd_event_exit()</function> earlier.</para>
+
+ <para>While the full positive and negative integer ranges may be used
+ for the exit code, care should be taken not pick exit codes that
+ conflict with regular exit codes returned by
+ <function>sd_event_loop()</function>, if these exit codes shall be
+ distinguishable.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_event_exit()</function> and
+ <function>sd_event_get_exit_code()</function> return 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><constant>-EINVAL</constant></term>
+
+ <listitem><para>The event loop object or error code pointer are invalid.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop was created in a different process.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop has exited already and all exit handlers are already processed.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENODATA</constant></term>
+
+ <listitem><para>The event loop has not been requested to exit yet.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_now" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_now</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_now</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_now</refname>
+
+ <refpurpose>Retrieve current event loop iteration timestamp</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_now</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>clockid_t <parameter>clock</parameter></paramdef>
+ <paramdef>uint64_t *<parameter>usec</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_now()</function> returns the timestamp
+ the most recent event loop iteration began. This timestamp is
+ taken right after after returning from the event sleep, and before
+ dispatching any event sources. The <parameter>event</parameter>
+ parameter takes the even loop object to retrieve the timestamp
+ from. The <parameter>clock</parameter> parameter specifies the clock to
+ retrieve the timestamp for, and is one of
+ <constant>CLOCK_REALTIME</constant> (or its equivalent
+ <constant>CLOCK_REALTIME_ALARM</constant>),
+ <constant>CLOCK_MONOTONIC</constant> or
+ <constant>CLOCK_BOOTTIME</constant> (or its equivalent
+ <constant>CLOCK_BOOTTIME_ALARM</constant>), see <citerefentry
+ project='man-pages'><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ for more information on the various clocks. The retrieved
+ timestamp is stored in the <parameter>usec</parameter> parameter,
+ in µs since the clock's epoch. If this function is invoked before
+ the first event loop iteration the current time is returned, as
+ reported by <function>clock_gettime()</function>. To distinguish
+ this case from a regular invocation the return value will be
+ positive non-zero in this case, while it is zero when the returned
+ timestamp refers to the actual event loop iteration.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>If the first event loop iteration has not run yet
+ <function>sd_event_now()</function> returns the requested
+ timestamp in <parameter>usec</parameter> and returns a positive,
+ non-zero return value. Otherwise, on success it will return the
+ iteration's timestamp in <parameter>usec</parameter> and 0 as
+ return value. On failure, the call returns a negative errno-style
+ error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <variablelist>
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>An invalid parameter was
+ passed.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop object was created in a
+ different process.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_new</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry project='man-pages'><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_set_watchdog" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_set_watchdog</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_set_watchdog</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_set_watchdog</refname>
+ <refname>sd_event_get_watchdog</refname>
+
+ <refpurpose>Enable event loop watchdog support</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_set_watchdog</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ <paramdef>int b</paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_get_watchdog</function></funcdef>
+ <paramdef>sd_event *<parameter>event</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_set_watchdog()</function> may be used to
+ enable or disable automatic watchdog notification support in the
+ event loop object specified in the <parameter>event</parameter>
+ parameter. Specifically, depending on the <parameter>b</parameter>
+ boolean argument this will make sure the event loop wakes up in
+ regular intervals and sends watchdog notification messages to the
+ service manager, if this was requested by the service
+ manager. Watchdog support is determined with
+ <citerefentry><refentrytitle>sd_watchdog_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ and watchdog messages are sent with
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>. See
+ the <varname>WatchdogSec=</varname> setting in
+ <citerefentry><refentrytitle>elogind.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ for details on how to enable watchdog support for a service and
+ the protocol used. The wake-up interval is chosen as half the
+ watchdog timeout declared by the service manager via the
+ <varname>$WATCHDOG_USEC</varname> environment variable. If the
+ service manager did not request watchdog notifications, or if the
+ process was not invoked by the service manager this call with a
+ true <parameter>b</parameter> parameter executes no
+ operation. Passing a false <parameter>b</parameter> parameter will
+ disable the automatic sending of watchdog notification messages if
+ it was enabled before. Newly allocated event loop objects have
+ this feature disabled.</para>
+
+ <para>The first watchdog notification message is sent immediately
+ when <function>set_event_set_watchdog()</function> is invoked with
+ a true <parameter>b</parameter> parameter.</para>
+
+ <para>The watchdog logic is designed to allow the service manager
+ to automatically detect services that ceased processing of
+ incoming events, and thus appear "hung". Watchdog notifications
+ are sent out only at the beginning of each event loop
+ iteration. If an event source dispatch function blocks for an
+ excessively long time and does not return execution to the event
+ loop quickly, this might hence cause the notification message to
+ be delayed, and possibly result in abnormal program termination,
+ as configured in the service unit file.</para>
+
+ <para><function>sd_event_get_watchdog()</function> may be used to
+ determine whether watchdog support was previously requested by a
+ call to <function>sd_event_set_watchdog()</function> with a true
+ <parameter>b</parameter> parameter and successfully
+ enabled.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_event_set_watchdog()</function> and
+ <function>sd_event_get_watchdog()</function> return a non-zero
+ positive integer if the service manager requested watchdog support
+ and watchdog support was successfully enabled. They return zero if
+ the service manager did not request watchdog support, or if
+ watchdog support was explicitly disabled with a false
+ <parameter>b</parameter> parameter. 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><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EINVAL</constant></term>
+
+ <listitem><para>The passed event loop object was invalid.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <citerefentry><refentrytitle>elogind</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_new</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_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_child</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_post</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_watchdog_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_notify</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>elogind.service</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_get_event" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_get_event</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_get_event</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_get_event</refname>
+
+ <refpurpose>Retrieve the event loop of an event source</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>sd_event* <function>sd_event_source_get_event</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_get_event()</function> may be used
+ to retrieve the event loop object the event source object specified
+ as <parameter>source</parameter> is associated with. The event
+ loop object is specified when creating an event source object with
+ calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ or
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_event_source_get_event()</function>
+ returns the associated event loop object. On failure, it returns
+ NULL.</para>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_get_pending" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_get_pending</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_get_pending</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_get_pending</refname>
+
+ <refpurpose>Determine pending state of event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_pending</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_get_pending()</function> may be
+ used to determine whether the event source object specified as
+ <parameter>source</parameter> has seen events but has not been
+ dispatched yet (and thus is marked "pending").</para>
+
+ <para>Event source objects initially are not marked pending, when
+ they are created with calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ with the exception of those created with
+ <citerefentry><refentrytitle>sd_event_add_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ which are immediately marked pending, and
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for which the "pending" concept is not defined. For details see
+ the respective manual pages.</para>
+
+ <para>In each event loop iteration one event source of those
+ marked pending is dispatched, in the order defined by the event
+ source priority, as set with
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para>
+
+ <para>For I/O event sources, as created with
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ the call
+ <citerefentry><refentrytitle>sd_event_get_io_revents</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ may be used to query the type of event pending in more
+ detail.</para>
+
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success,
+ <function>sd_event_source_get_pending()</function> returns an
+ integer greater than zero when the event source is marked pending,
+ and zero when the event source is not marked pending. On failure,
+ it returns a negative errno-style error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <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>
+
+ <varlistentry>
+ <term><constant>-EDOM</constant></term>
+
+ <listitem><para><parameter>source</parameter> refers to an
+ event source object created with
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop is already terminated.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2014 Zbigniew Jędrzejewski-Szmek
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_set_description" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_set_description</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>More text</contrib>
+ <firstname>Zbigniew</firstname>
+ <surname>Jędrzejewski-Szmek</surname>
+ <email>zbyszek@in.waw.pl</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_set_description</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_set_description</refname>
+ <refname>sd_event_source_get_description</refname>
+
+ <refpurpose>Set or retrieve descriptive names of event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_description</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>const char *<parameter>description</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_description</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>const char **<parameter>description</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_set_description()</function> may
+ be used to set an arbitrary descriptive name for the event source
+ object specified as <parameter>source</parameter>. This name will
+ be used in debugging messages generated by
+ <citerefentry><refentrytitle>sd-event</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ for this event source, and may be queried using
+ <function>sd_event_source_get_description()</function> for
+ debugging purposes. The <parameter>description</parameter> parameter shall
+ point to a <constant>NUL</constant>-terminated string or be
+ <constant>NULL</constant>. In the latter case, the descriptive
+ name will be unset. The string is copied internally, hence the
+ <parameter>description</parameter> argument is not referenced
+ after the function returns.</para>
+
+ <para><function>sd_event_source_get_description()</function> may
+ be used to query the current descriptive name assigned to the
+ event source object <parameter>source</parameter>. It returns a
+ pointer to the current name in <parameter>description</parameter>,
+ stored in memory internal to the event source. The memory is
+ invalidated when the event source is destroyed or the descriptive
+ name is changed.</para>
+
+ <para>Event source objects generally have no description set when
+ they are created, except for UNIX signal event sources created
+ with
+ <citerefentry><refentrytitle>sd_event_add_signal</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ whose descriptive name is initialized to the signal's C constant
+ name (e.g. <literal>SIGINT</literal> or
+ <literal>SIGTERM</literal>).</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_event_source_set_description()</function> and
+ <function>sd_event_source_get_description()</function> return a
+ non-negative 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><constant>-EINVAL</constant></term>
+
+ <listitem><para><parameter>source</parameter> is not a valid
+ pointer to an <structname>sd_event_source</structname>
+ object or the <parameter>description</parameter> argument for
+ <function>sd_event_source_get_description()</function> is
+ <constant>NULL</constant>.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory to copy the
+ name.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ENXIO</constant></term>
+
+ <listitem><para>No name was set for the event
+ source.</para></listitem>
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_set_enabled" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_set_enabled</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_set_enabled</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_set_enabled</refname>
+ <refname>sd_event_source_get_enabled</refname>
+ <refname>SD_EVENT_ON</refname>
+ <refname>SD_EVENT_OFF</refname>
+ <refname>SD_EVENT_ONESHOT</refname>
+
+ <refpurpose>Enable or disable event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcsynopsisinfo><token>enum</token> {
+ <constant>SD_EVENT_OFF</constant> = 0,
+ <constant>SD_EVENT_ON</constant> = 1,
+ <constant>SD_EVENT_ONESHOT</constant> = -1,
+};</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_enabled</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>int <parameter>enabled</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_enabled</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>int *<parameter>enabled</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_set_enabled()</function> may be
+ used to enable or disable the event source object specified as
+ <parameter>source</parameter>. The <parameter>enabled</parameter>
+ parameter takes one of <constant>SD_EVENT_ON</constant> (to
+ enable), <constant>SD_EVENT_OFF</constant> (to disable) or
+ <constant>SD_EVENT_ONESHOT</constant>. If invoked with
+ <constant>SD_EVENT_ONESHOT</constant> the event source will be
+ enabled but automatically reset to
+ <constant>SD_EVENT_OFF</constant> after the event source was
+ dispatched once.</para>
+
+ <para>Event sources that are disabled will not result in event
+ loop wakeups and will not be dispatched, until they are enabled
+ again.</para>
+
+ <para><function>sd_event_source_get_enabled()</function> may be
+ used to query whether the event source object
+ <parameter>source</parameter> is currently enabled or not. It
+ returns the enablement state in
+ <parameter>enabled</parameter>.</para>
+
+ <para>Event source objects are enabled when they are first created
+ with calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>. However,
+ depending on the event source type they are enabled continously
+ (<constant>SD_EVENT_ON</constant>) or only for a single invocation
+ of the event source handler
+ (<constant>SD_EVENT_ONESHOT</constant>). For details see the
+ respective manual pages.</para>
+
+ <para>As event source objects stay active and may be dispatched as
+ long as there is at least one reference to them, in many cases it
+ is a good idea to combine a call to
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ with a prior call to
+ <function>sd_event_source_set_enabled()</function> with
+ <constant>SD_EVENT_OFF</constant>, to ensure the event source is
+ not dispatched again until all other remaining references are dropped.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success, <function>sd_event_source_set_enabled()</function> and
+ <function>sd_event_source_get_enabled()</function> return a
+ non-negative 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><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>
+
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_unref</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_set_prepare" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_set_prepare</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_set_prepare</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_set_prepare</refname>
+
+ <refpurpose>Set a preparation callback for event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_prepare</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>sd_event_handler_t <parameter>callback</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>typedef int (*<function>sd_event_handler_t</function>)</funcdef>
+ <paramdef>sd_event_source *<parameter>s</parameter></paramdef>
+ <paramdef>void *<parameter>userdata</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_set_prepare()</function> may be
+ used to set a prepartion callback for the event source object
+ specified as <parameter>source</parameter>. The callback function
+ specified as <parameter>callback</parameter> will be invoked
+ immediately before the event loop goes to sleep to wait for
+ incoming events. It is invoked with the user data pointer passed
+ when the event source was created. The callback function may be
+ used to reconfigure the precise events to wait for. If the
+ <parameter>callback</parameter> parameter is passed as NULL the
+ callback function is reset. </para>
+
+ <para>Event source objects have no preparation callback associated
+ when they are first created with calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Preparation
+ callback functions are supported for all event source types with
+ the exception of those created with
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Preparation
+ callback functions are dispatched in the order indicated by the
+ event source's priority field, as set with
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>. Preparation
+ callbacks of disabled event sources (see
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>)
+ are not invoked.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success,
+ <function>sd_event_source_set_prepare()</function> returns a
+ non-negative integer. On failure, it returns a negative
+ errno-style error code.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <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>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop is already terminated.</para></listitem>
+
+ </varlistentry>
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-EDOM</constant></term>
+
+ <listitem><para>The specified event source has been created
+ with
+ <citerefentry><refentrytitle>sd_event_add_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para></listitem>
+
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_priority</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_userdata</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_set_priority" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_set_priority</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_set_priority</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_set_priority</refname>
+ <refname>sd_event_source_get_priority</refname>
+ <refname>SD_EVENT_PRIORITY_IMPORTANT</refname>
+ <refname>SD_EVENT_PRIORITY_NORMAL</refname>
+ <refname>SD_EVENT_PRIORITY_IDLE</refname>
+
+ <refpurpose>Set or retrieve the priority of event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/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,
+};</funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_set_priority</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>int64_t <parameter>priority</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>int <function>sd_event_source_get_priority</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>int64_t *<parameter>priority</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_set_priority()</function> may be
+ used to set the priority for the event source object specified as
+ <parameter>source</parameter>. The priority is specified as an
+ arbitrary signed 64bit integer. The priority is initialized to
+ <constant>SD_EVENT_PRIORITY_NORMAL</constant> (0) when the event
+ source is allocated with a call such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ or
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ and may be changed with this call. If multiple event sources have seen events at the same time, they are dispatched in the order indicated by the
+ event sources' priorities. Event sources with smaller priority
+ values are dispatched first. As well-known points of reference,
+ the constants <constant>SD_EVENT_PRIORITY_IMPORTANT</constant>
+ (-100), <constant>SD_EVENT_PRIORITY_NORMAL</constant> (0) and
+ <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
+ signed integer range is available for ordering event
+ sources.</para>
+
+ <para>Priorities define the order in which event sources that have
+ seen events are dispatched. Care should be taken to ensure that
+ high-priority event sources (those with negative priority values
+ assigned) do not cause starvation of low-priority event sources
+ (those with positive priority values assigned).</para>
+
+ <para>The order in which event sources with the same priority are
+ dispatched is undefined, but the event loop generally tries to
+ dispatch them in the order it learnt about events on them. As the
+ backing kernel primitives do not provide accurate information
+ about the order in which events occured this is not necessarily
+ 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
+ particular event sources do not starve or dominate the event
+ loop.</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>
+
+ <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>
+
+ <refsect1>
+ <title>Errors</title>
+
+ <para>Returned errors may indicate the following problems:</para>
+
+ <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>
+
+ <varlistentry>
+ <term><constant>-ENOMEM</constant></term>
+
+ <listitem><para>Not enough memory.</para></listitem>
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ESTALE</constant></term>
+
+ <listitem><para>The event loop is already terminated.</para></listitem>
+
+ </varlistentry>
+
+ <varlistentry>
+ <term><constant>-ECHILD</constant></term>
+
+ <listitem><para>The event loop has been created in a different process.</para></listitem>
+
+ </varlistentry>
+
+ </variablelist>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_set_userdata" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_set_userdata</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_set_userdata</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_set_userdata</refname>
+ <refname>sd_event_source_get_userdata</refname>
+
+ <refpurpose>Set or retrieve user data pointer of event sources</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>void* <function>sd_event_source_set_userdata</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ <paramdef>void *<parameter>userdata</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>void* <function>sd_event_source_get_userdata</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_set_userdata()</function> may be
+ used to set an arbitrary user data pointer for the event source
+ object specified as <parameter>source</parameter>. The user data
+ pointer is usually specified when creating an event source object
+ with calls such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ or
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ and may be updated with this call. The user data pointer is also
+ passed to all handler callback functions associated with the event
+ source. The <parameter>userdata</parameter> parameter specifies
+ the new user data pointer to set, the function returns the
+ previous user data pointer. Note that <constant>NULL</constant> is
+ a valid user data pointer.</para>
+
+ <para><function>sd_event_source_get_userdata()</function> may be
+ used to query the current user data pointer assigned to the event
+ source object <parameter>source</parameter>.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para>On success,
+ <function>sd_event_source_set_userdata()</function> and
+ <function>sd_event_source_get_userdata()</function> return the
+ previously set user data pointer. On failure, they return
+ NULL.</para>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_description</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
--- /dev/null
+<?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 elogind.
+
+ Copyright 2015 Lennart Poettering
+
+ elogind 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.
+
+ elogind 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 elogind; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="sd_event_source_unref" xmlns:xi="http://www.w3.org/2001/XInclude">
+
+ <refentryinfo>
+ <title>sd_event_source_unref</title>
+ <productname>elogind</productname>
+
+ <authorgroup>
+ <author>
+ <contrib>Developer</contrib>
+ <firstname>Lennart</firstname>
+ <surname>Poettering</surname>
+ <email>lennart@poettering.net</email>
+ </author>
+ </authorgroup>
+ </refentryinfo>
+
+ <refmeta>
+ <refentrytitle>sd_event_source_unref</refentrytitle>
+ <manvolnum>3</manvolnum>
+ </refmeta>
+
+ <refnamediv>
+ <refname>sd_event_source_unref</refname>
+ <refname>sd_event_source_ref</refname>
+
+ <refpurpose>Increase or decrease event source reference counters</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcsynopsisinfo>#include <elogind/sd-event.h></funcsynopsisinfo>
+
+ <funcprototype>
+ <funcdef>sd_event_source* <function>sd_event_source_unref</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ <funcprototype>
+ <funcdef>sd_event_source* <function>sd_event_source_ref</function></funcdef>
+ <paramdef>sd_event_source *<parameter>source</parameter></paramdef>
+ </funcprototype>
+
+ </funcsynopsis>
+ </refsynopsisdiv>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para><function>sd_event_source_unref()</function> may be used to
+ decrement by one the reference counter of the event source object
+ specified as <parameter>source</parameter>. The reference counter
+ is initially set to one, when the event source is created with calls
+ such as
+ <citerefentry><refentrytitle>sd_event_add_io</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ or
+ <citerefentry><refentrytitle>sd_event_add_time</refentrytitle><manvolnum>3</manvolnum></citerefentry>. When
+ the reference counter reaches zero it is removed from its event loop
+ object and destroyed.</para>
+
+ <para><function>sd_event_source_ref()</function> may be used
+ to increase by one the reference counter of the event source object
+ specified as <parameter>source</parameter>.</para>
+
+ <para>Both functions execute no operation if the passed event
+ source object is <constant>NULL</constant>.</para>
+
+ <para>Note that event source objects stay alive and may be
+ dispatched as long as they have a reference counter greater than
+ zero. In order to drop a reference of an event source and make
+ sure the associated event source handler function is not called
+ anymore it is recommended to combine a call of
+ <function>sd_event_source_unref()</function> with a prior call to
+ <function>sd_event_source_set_enabled()</function> with
+ <constant>SD_EVENT_OFF</constant>.</para>
+ </refsect1>
+
+ <refsect1>
+ <title>Return Value</title>
+
+ <para><function>sd_event_source_unref()</function> always returns
+ <constant>NULL</constant>.
+ <function>sd_event_source_ref()</function> always returns the
+ event source object passed in.</para>
+ </refsect1>
+
+ <xi:include href="libelogind-pkgconfig.xml" />
+
+ <refsect1>
+ <title>See Also</title>
+
+ <para>
+ <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_defer</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>
+ </para>
+ </refsect1>
+
+</refentry>
~ianmdlvl / elogind.git / commitdiff