Symbian3/SDK/Source/GUID-FE2E8E58-6656-534E-A052-095AF559A482.dita
author Dominic Pinkman <dominic.pinkman@nokia.com>
Fri, 11 Jun 2010 15:24:34 +0100
changeset 9 59758314f811
parent 0 89d6a7a84779
permissions -rw-r--r--
Week 23 contribution of PDK documentation content. See release notes for details. Fixes bugs Bug 2714, Bug 462.

<?xml version="1.0" encoding="utf-8"?>
<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->
<!-- This component and the accompanying materials are made available under the terms of the License 
"Eclipse Public License v1.0" which accompanies this distribution, 
and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->
<!-- Initial Contributors:
    Nokia Corporation - initial contribution.
Contributors: 
-->
<!DOCTYPE concept
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-FE2E8E58-6656-534E-A052-095AF559A482" xml:lang="en"><title>Alarm
Time Formats</title><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>The Alarm Server supports two types of time formats used to express the
expiry time of an alarm: </p>
<ul>
<li id="GUID-90BAC4D4-DD00-51D2-8661-51E2680DA315"><p> <b>Fixed time format</b> -
The alarm expires at the given UTC time and has no associated UTC offset.
The alarm is not rescheduled when an UTC offset or DST change occur. </p> </li>
<li id="GUID-A007966C-84AD-56E2-B692-7CAE4B3A648F"><p> <b>Floating time format</b> -
The alarm expires at the given local (wall clock) time in the current UTC
offset and are re-scheduled when either the UTC offset or DST change occurs. </p> </li>
</ul>
<p>The Alarm Server maintains a queue of alarms and the format of these alarms
may be either fixed or floating time format. </p>
<p>Hence, if the user adds an alarm defining one of its characteristics as <xref href="GUID-20A42BF7-A0F5-3177-9592-E3AE097B4CF2.dita#GUID-20A42BF7-A0F5-3177-9592-E3AE097B4CF2/GUID-EBAEFA64-7892-32D6-B8BF-EBE4EC9AFB83"><apiname>TAlarmCharacteristics::EAlarmCharacteristicsIsFixed</apiname></xref>,
then it is added in the alarm queue as fixed time format based alarm. </p>
<p> </p>
<p> <b>NOTE</b>: </p>
<ul>
<li id="GUID-14A58869-C859-5F7B-A28A-319F180DD8CE"><p> <b>UTC time</b> is
the non-secure system time in UTC (UTC time range is from 0-24, so after 12,
the time is expressed in PM). </p> <p> <b>Standard Time</b> = UTC Time + Timezone/UTC
offset </p> <p> <b>Wall Clock/local time</b> = UTC Time + Timezone/UTC offset
± DST offset </p> </li>
<li id="GUID-24513E63-880C-5147-9A5F-AFF047370175"><p>All alarms (irrespective
of the time format) undergo rescheduling and re-evaluation of their next due
time (considering their repeat definition) only when either system time/date
or workdays change. </p> </li>
<li id="GUID-80D105D4-D99D-56F3-9D92-11F7686FF3C1"><p>Only the floating time
format based alarms undergo re-scheduling and re-evaluation of their next
due time if the system time/date, workdays, UTC offset changes or DST rollover
event occurs. </p> </li>
</ul>
</conbody></concept>