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diff --git a/man/sd_event_add_time.xml b/man/sd_event_add_time.xml deleted file mode 100644 index 5496b71529..0000000000 --- a/man/sd_event_add_time.xml +++ /dev/null @@ -1,313 +0,0 @@ -<?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 2014 Lennart Poettering - - systemd is free software; you can redistribute it and/or modify it - under the terms of the GNU Lesser General Public License as published by - the Free Software Foundation; either version 2.1 of the License, or - (at your option) any later version. - - systemd is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public License - along with systemd; If not, see <http://www.gnu.org/licenses/>. ---> - -<refentry id="sd_event_add_time" xmlns:xi="http://www.w3.org/2001/XInclude"> - - <refentryinfo> - <title>sd_event_add_time</title> - <productname>systemd</productname> - - <authorgroup> - <author> - <contrib>Developer</contrib> - <firstname>Lennart</firstname> - <surname>Poettering</surname> - <email>lennart@poettering.net</email> - </author> - </authorgroup> - </refentryinfo> - - <refmeta> - <refentrytitle>sd_event_add_time</refentrytitle> - <manvolnum>3</manvolnum> - </refmeta> - - <refnamediv> - <refname>sd_event_add_time</refname> - <refname>sd_event_source_get_time</refname> - <refname>sd_event_source_set_time</refname> - <refname>sd_event_source_get_time_accuracy</refname> - <refname>sd_event_source_set_time_accuracy</refname> - <refname>sd_event_source_get_time_clock</refname> - <refname>sd_event_time_handler_t</refname> - - <refpurpose>Add a timer event source to an event loop</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcsynopsisinfo>#include <systemd/sd-event.h></funcsynopsisinfo> - - <funcsynopsisinfo><token>typedef</token> struct sd_event_source sd_event_source;</funcsynopsisinfo> - - <funcprototype> - <funcdef>typedef int (*<function>sd_event_time_handler_t</function>)</funcdef> - <paramdef>sd_event_source *<parameter>s</parameter></paramdef> - <paramdef>uint64_t <parameter>usec</parameter></paramdef> - <paramdef>void *<parameter>userdata</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_add_time</function></funcdef> - <paramdef>sd_event *<parameter>event</parameter></paramdef> - <paramdef>sd_event_source **<parameter>source</parameter></paramdef> - <paramdef>clockid_t <parameter>clock</parameter></paramdef> - <paramdef>uint64_t <parameter>usec</parameter></paramdef> - <paramdef>uint64_t <parameter>accuracy</parameter></paramdef> - <paramdef>sd_event_time_handler_t <parameter>handler</parameter></paramdef> - <paramdef>void *<parameter>userdata</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_get_time</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>uint64_t *<parameter>usec</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_set_time</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>uint64_t <parameter>usec</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_get_time_accuracy</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>uint64_t *<parameter>usec</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_set_time_accuracy</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>uint64_t <parameter>usec</parameter></paramdef> - </funcprototype> - - <funcprototype> - <funcdef>int <function>sd_event_source_get_time_clock</function></funcdef> - <paramdef>sd_event_source *<parameter>source</parameter></paramdef> - <paramdef>clockid_t *<parameter>clock</parameter></paramdef> - </funcprototype> - - </funcsynopsis> - </refsynopsisdiv> - - <refsect1> - <title>Description</title> - - <para><function>sd_event_add_time()</function> adds a new timer 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>clock</parameter> parameter takes a clock identifier, one - of <constant>CLOCK_REALTIME</constant>, <constant>CLOCK_MONOTONIC</constant>, <constant>CLOCK_BOOTTIME</constant>, - <constant>CLOCK_REALTIME_ALARM</constant>, or <constant>CLOCK_BOOTTIME_ALARM</constant>. See - <citerefentry><refentrytitle>timerfd_create</refentrytitle><manvolnum>2</manvolnum></citerefentry> for details - regarding the various types of clocks. The <parameter>usec</parameter> parameter specifies the earliest time, in - microseconds (µs), relative to the clock's epoch, when the timer shall be triggered. If a time already in the past - is specified (including <constant>0</constant>), this timer source "fires" immediately and is ready to be - dispatched. If the parameter is specified as <constant>UINT64_MAX</constant> the timer event will never elapse, - which may be used as an alternative to explicitly disabling a timer event source with - <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry>. The - <parameter>accuracy</parameter> parameter specifies an additional accuracy value in µs specifying how much the - timer event may be delayed. Use <constant>0</constant> to select the default accuracy (250ms). Use 1µs for maximum - accuracy. Consider specifying 60000000µs (1min) or larger for long-running events that may be delayed - substantially. Picking higher accuracy values allows the system to coalesce timer events more aggressively, - improving power efficiency. The <parameter>handler</parameter> parameter shall reference a function to call when - the timer elapses. The handler function will be passed the <parameter>userdata</parameter> pointer, which may be - chosen freely by the caller. The handler is also passed the configured trigger time, even if it is actually called - slightly later, subject to the specified accuracy value, the kernel timer slack (see - <citerefentry><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry>), and additional - scheduling latencies. To query the actual time the handler was called use - <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> - - <para>By default, the timer will elapse once - (<constant>SD_EVENT_ONESHOT</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 a timer event set to <constant>SD_EVENT_ON</constant> will - fire continuously unless its configured time is updated using - <function>sd_event_source_set_time()</function>. - </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 if it is still referenced, - disable the event source using - <citerefentry><refentrytitle>sd_event_source_set_enabled</refentrytitle><manvolnum>3</manvolnum></citerefentry> - with <constant>SD_EVENT_OFF</constant>.</para> - - <para>If the second parameter of - <function>sd_event_add_time()</function> is - <constant>NULL</constant> 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>If the <parameter>handler</parameter> to - <function>sd_event_add_time()</function> is - <constant>NULL</constant>, and the event source fires, this will - be considered a request to exit the event loop. In this case, the - <parameter>userdata</parameter> parameter, cast to an integer, is - used for the exit code passed to - <citerefentry><refentrytitle>sd_event_exit</refentrytitle><manvolnum>3</manvolnum></citerefentry>.</para> - - <para>Use <constant>CLOCK_BOOTTIME_ALARM</constant> and - <constant>CLOCK_REALTIME_ALARM</constant> to define event sources - that may wake up the system from suspend.</para> - - <para>In order to set up relative timers (that is, relative to the - current time), retrieve the current time via - <citerefentry><refentrytitle>sd_event_now</refentrytitle><manvolnum>3</manvolnum></citerefentry>, - add the desired timespan to it, and use the result as - the <parameter>usec</parameter> parameter to - <function>sd_event_add_time()</function>.</para> - - <para>In order to set up repetitive timers (that is, timers that - are triggered in regular intervals), set up the timer normally, - for the first invocation. Each time the event handler is invoked, - update the timer's trigger time with - <citerefentry><refentrytitle>sd_event_source_set_time</refentrytitle><manvolnum>3</manvolnum></citerefentry> for the next timer - iteration, and reenable the timer using - <function>sd_event_source_set_enabled()</function>. To calculate - the next point in time to pass to - <function>sd_event_source_set_time()</function>, either use as - base the <parameter>usec</parameter> parameter passed to the timer - callback, or the timestamp returned by - <function>sd_event_now()</function>. In the former case timer - events will be regular, while in the latter case the scheduling - latency will keep accumulating on the timer.</para> - - <para><function>sd_event_source_get_time()</function> retrieves - the configured time value of an event source created - previously with <function>sd_event_add_time()</function>. It takes - the event source object and a pointer to a variable to store the - time in, relative to the selected clock's epoch, in µs.</para> - - <para><function>sd_event_source_set_time()</function> changes the - time of an event source created previously with - <function>sd_event_add_time()</function>. It takes the event - source object and a time relative to the selected clock's epoch, - in µs.</para> - - <para><function>sd_event_source_get_time_accuracy()</function> - retrieves the configured accuracy value of an event source - created previously with <function>sd_event_add_time()</function>. It - takes the event source object and a pointer to a variable to store - the accuracy in. The accuracy is specified in µs.</para> - - <para><function>sd_event_source_set_time_accuracy()</function> - changes the configured accuracy of a timer event source created - previously with <function>sd_event_add_time()</function>. It takes - the event source object and accuracy, in µs.</para> - - <para><function>sd_event_source_get_time_clock()</function> - retrieves the configured clock of an event source created - previously with <function>sd_event_add_time()</function>. It takes - the event source object and a pointer to a variable to store the - clock identifier in.</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 values 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>-EOPNOTSUPP</constant></term> - - <listitem><para>The selected clock is not supported by the event loop implementation.</para></listitem> - - </varlistentry> - - <varlistentry> - <term><constant>-EDOM</constant></term> - - <listitem><para>The passed event source is not a timer event source.</para></listitem> - </varlistentry> - </variablelist> - </refsect1> - - <xi:include href="libsystemd-pkgconfig.xml" /> - - <refsect1> - <title>See Also</title> - - <para> - <citerefentry><refentrytitle>systemd</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_io</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 project='man-pages'><refentrytitle>clock_gettime</refentrytitle><manvolnum>2</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>timerfd_create</refentrytitle><manvolnum>2</manvolnum></citerefentry>, - <citerefentry project='man-pages'><refentrytitle>prctl</refentrytitle><manvolnum>2</manvolnum></citerefentry> - </para> - </refsect1> - -</refentry> |