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<concept id="GUID-114D4F3F-9358-5B50-94DC-45CCBA783DF4" xml:lang="en"><title>Alarm

Server Overview</title><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>Alarm Server is a system server, which starts during device start-up. It

is responsible for maintaining a queue of all system-wide alarms. </p>

<p>It allows clients to query the status of alarms, set alarms, remove alarms

and perform other utility functions. The Alarm client API allows other components

to interact with the Alarm Server. The Alarm Server sends notification of

alarm expiry to the Alert Server, which then notifies the Alarm UI to display

dialogs and play sound. </p>

<p>The typical clients of Alarm Server include Clock and Calendar applications. </p>

<section><title>Purpose</title> <p>The Alarm Server manages the alarms in

the system and provides the following functionality: </p> <ul>

<li id="GUID-56175798-4930-55A3-ACD8-848192C07A63"><p>adding, updating and

deleting alarms. </p> </li>

<li id="GUID-FCF13562-7E88-5A5B-84B9-05B7934E7277"><p>getting and setting

client-specific data associated with the alarm. </p> </li>

<li id="GUID-44A49D6B-A12E-5C05-A7D7-9BDE3E430521"><p>performing alarm category-based

operations such as retrieval and deletion. Retrieving alarm information includes

alarm count, unique identifiers based on alarm states. </p> </li>

<li id="GUID-57B8169F-1166-5534-9236-D1C367AB2413"><p>getting and setting

Alarm Server’s global sound state and play intervals. </p> </li>

<li id="GUID-7BB3AD26-5650-5B6A-B656-76A24EF9086A"><p>notifying the client

when alarm settings change and when the alarm expires. </p> </li>

</ul> </section>

<section><title>Key concepts and terms</title> <dl>

<dlentry>

<dt>Duration</dt>

<dd><p>It is the time period, in seconds, for which the alarm sound is played. </p> </dd>

</dlentry>

<dlentry>

<dt>Offset</dt>

<dd><p>It is the time (in minutes) duration of alarm sound played after the

alarm expiry. </p> </dd>

</dlentry>

<dlentry>

<dt>Alarm play interval</dt>

<dd><p>Alarm play interval consists of duration and an offset. At each offset,

the Alarm Server makes a request to the Alarm Alert Server to display the

alarm dialog and play the alarm sound. </p> </dd>

</dlentry>

<dlentry>

<dt>Universal Time Coordinated (UTC)</dt>

<dd><p>It is the international time standard. It is the current term for what

was commonly referred as Greenwich Meridian Time (GMT) . Zero hours UTC is

midnight in Greenwich England, which lies on the zero longitudinal meridian.

Universal time is based on a 24-hour clock. Therefore, afternoon hours such

as 4 PM are expressed as 16:00 UTC. </p> </dd>

</dlentry>

<dlentry>

<dt>Daylight Saving Time (DST)</dt>

<dd><p>Daylight Saving Time or Summer Time, is a way of utilizing more daylight

by advancing the local time by one hour during the summer. </p> </dd>

</dlentry>

<dlentry>

<dt>Session alarms</dt>

<dd><p>The alarms that are removed from the alarm queue when their session

owners disconnect are referred as Session Alarms. </p> </dd>

</dlentry>

<dlentry>

<dt>Non-Session alarms</dt>

<dd><p>The alarms that continue to persist in the alarm queue, even after

their session owner which added these alarms disconnect, are referred as Non-Session

alarms. These alarms are also referred to as Orphaned Session alarms. </p> </dd>

</dlentry>

<dlentry>

<dt>Wake-Up alarms</dt>

<dd><p>An alarm that wakes-up the device if the device is switched OFF when

the alarm occurs, is referred to as Wake-Up alarm. </p> </dd>

</dlentry>

<dlentry>

<dt>Skipped/Missed Calendar alarms</dt>

<dd><p>An alarm which does not expire normally because of an environment change

but the alarm’s expiry time is put in the past, is referred as Skipped Calendar

alarms. </p> </dd>

</dlentry>

</dl> </section>

<section><title>Architecture</title> <p>Alarm Server is implemented using

the Symbian platform IPC client-server architecture. It has an interface to

the Alarm Alert server, which is delivered as part of the Application Framework

(UIKON component). Alarm Alert Server is responsible for displaying the alarm

dialog when an alarm expires. The Alarm Server implements the Alarm Alert

server’s client side DLL to send and receive notifications to and from the

Alarm UI. Alarm Alert Server is a part of the UIKON server (<codeph>Eiksrv.exe</codeph>).

The Alarm Server itself implements the client-side APIs since it is the only

client for the Alarm Alert server. The following diagram illustrates the Alarm

Server architecture: </p> <fig id="GUID-D6309F3E-4835-5703-8929-8A108CC5D376">

<title>              Alarm Server Architecture            </title>

<image href="GUID-7CD8F0E3-68C3-5939-A96D-547740D796E5_d0e152190_href.png" placement="inline"/>

</fig> <p><b>Alarm Client and Alarm Shared</b> </p> <p>They are the static

interface DLLs. Alarm client is the client side of the Alarm Server, which

allows other components to interact with the Alarm Server. </p> <p>The Alarm

Shared facilitates a common format shared across server and its clients for

providing definition for an alarm. It consists of shared objects such as alarm

class, IPC messages, repeat definitions, alarm states. </p> <p><b>Alarm Server</b> </p> <p>Alarm

Server manages all alarms on the device and enables client UI applications

to use the services provided by the Alarm Server. It relies on the Alarm UI

to notify, which includes displaying and playing sounds. </p> <p>It uses a

resource file to configure the sound intervals required for the alarm to repeat.

The compiled resource file resides in the private directory of the Alarm Server.

The resource file is used only for initial configuration. </p> <p>Alarm Server

configurations are stored in <codeph>AlarmServer.ini</codeph> file and <codeph>Backup_Registration.xml</codeph> file

performs a passive backup of this <codeph>.ini</codeph> file to the PC-side

at runtime. For secure backup of this <codeph>.ini</codeph> file, <codeph>backuprestorenotification.lib</codeph> is

used. For more information on the resource file and backup, refer to the <xref href="GUID-A5F65344-BE05-5295-85BB-E8114505FB82.dita">Alarm Sound Play Control</xref>. </p> <p>It

provides Publish and Subscribe keys to enable the client to receive notifications

of the changes to the Alarm Server. The P&amp;S key are: </p> <ul>

<li id="GUID-BDB9B185-B20A-5598-AD66-29EE0DC25224"><p> <codeph>KMissingAlarmPubSubKey</codeph> -

provides information about missed calendar alarms, which were missed due to

the device being in the shutdown state. </p> </li>

<li id="GUID-D0ABBB1C-0796-5E5B-A7E0-216ECAD537F5"><p> <codeph>KSkippedAlarmInstancesPubSubKey</codeph> -

provides information about skipped calendar alarms instances which can used

for searching the required data in the calendar store. </p> </li>

<li id="GUID-2FCE4A66-7199-5B74-AE68-DCD702672FD3"><p> <codeph>KWakeupAlarmPubSubKey</codeph> -

provides information about an active wake-up alarm which is set or unset. </p> </li>

</ul> <p>For more information on Skipped Calendar Alarms and Wake-up Alarms,

refer to <xref href="GUID-12A32F8E-0C53-5311-9B2B-8E0EA373ED08.dita">Types of Alarm</xref> section. </p> <p>It

listens to the following events: </p> <ul>

<li id="GUID-266EBC9B-E834-5DCD-9B5F-F9E4A13EFF4E"><p>DST rollover - Using <codeph>KDSTChangePropertyKey</codeph> P&amp;S

key, Alarm Server listens to DST rollover information from <xref href="GUID-3CD0CEB1-CE8B-5108-A7F7-5E1414020C37.dita">Time

Zone Server</xref> resulting in the change of wall clock/local time clock. </p> </li>

<li id="GUID-F759197E-A22E-5C4F-89B7-247BF64134E1"><p>System state changes

- Using <xref href="GUID-788BD091-186A-5E25-B058-952C7629A8D4.dita">System State

Manager</xref> (SSM), Alarm Server listens to the system state changes (normal

and shutdown states) to synchronize the backup of the alarm server queue to

the <codeph>AlarmServer.ini</codeph> backup file. </p> </li>

<li id="GUID-42C04AB7-8BCC-57D6-A716-4F6B12F5AC30"><p>Environment change -

Using <xref href="GUID-7C6D3479-2159-5A9B-9970-0B3E625442A6.dita">Environment Change

Notifier</xref> (<codeph>bafl.dll</codeph>), Alarm Server listens to the changes

in the environment, such as system time/date change, workdays change or UTC

offset change. </p> </li>

</ul> <p><b>UIKON Server</b> </p> <p>UIKON server is responsible for starting

the Alarm Server at the device boot-up, by loading the polymorphic DLL, EIKSRVUI

provided by the device creator. </p> <p>It is also responsible for playing

sounds, flashing lights and displaying the message. Through the UIKON server,

alarms can be cleared, snoozed or silenced. Alarm server implements and uses

the client side interface. Alarm UI implements the server side of the UIKON

server. </p> </section>

<section><title>APIs</title> <p>The Alarm Server provides the following client

API: </p> <table id="GUID-60D7DF2B-BA9C-5CEC-9048-6B8536D04CFE">

<tgroup cols="2"><colspec colname="col0"/><colspec colname="col1"/>

<thead>

<row>

<entry>API</entry>

<entry>Description</entry>

</row>

</thead>

<tbody>

<row>

<entry><p> <xref href="GUID-3598EAEE-0EF4-35A2-89E5-F3B2555B1AB4.dita"><apiname>RASCliSession</apiname></xref>  </p> </entry>

<entry><p>Client interface to Alarm session on Symbian Platform. </p></entry>

</row>

</tbody>

</tgroup>

</table> </section>

<section><title>Typical uses</title> <p>The following are the typical use

cases of Alarm Server: </p> <ul>

<li id="GUID-854E8EA9-3194-5D0E-8BB5-3006B04BB6D3"><p>Using Alarm Server to

add, update and delete alarms, set alarm status and so on. </p> </li>

<li id="GUID-9A999DC2-6D48-58B8-B251-F22A88A1978C"><p>Playing an alarm continuously. </p> </li>

<li id="GUID-2D7D1AF6-2728-59CF-BD92-32D97FD6C6B6"><p>Activating an alarm

on specified days. </p> </li>

</ul> </section>

</conbody><related-links>

<link href="GUID-E6788741-EF34-57B7-B4D4-8AAC21B25774.dita"><linktext>Alarm Server

Concepts</linktext></link>

<link href="GUID-63730EBD-E5C1-5BA9-AB71-8FF668ECEF00.dita"><linktext>Alarm Server

Tutorials</linktext></link>

<link href="GUID-7BCA8B7A-E250-5452-9837-26C60F71F14F.dita"><linktext>Alarm Server

Reference</linktext></link>

<link href="GUID-74153585-D483-5761-85B6-2CF2D2615C00.dita"><linktext>Alarm Server

Example</linktext></link>

</related-links></concept>