1 <?xml version="1.0" encoding="utf-8"?>

     2 <!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->

     3 <!-- This component and the accompanying materials are made available under the terms of the License 

     4 "Eclipse Public License v1.0" which accompanies this distribution, 

     5 and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->

     6 <!-- Initial Contributors:

     7     Nokia Corporation - initial contribution.

     8 Contributors: 

     9 -->

    10 <!DOCTYPE concept

    11   PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">

    12 <concept id="GUID-88A5F321-17BA-566B-B025-22DB11664E54" xml:lang="en"><title>Public

    13 and Subscribe Events for Backup and Restore</title><shortdesc> This section describes the subscribe and publish flag for backup

    14 and restore. </shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <section><title>Description</title><p>Applications and servers are made aware

    16 that a backup or restore takes place through the <xref href="GUID-A81C65CF-CF4E-571C-8080-9D387F46AAD6.dita">Publish

    17 and Subscribe</xref> (P&amp;S) events. The P&amp;S server maintains a list

    18 of subscribers expressing an interest in the backup and restore <i>status

    19 flag</i>. Any published changes to this flag by the Backup Engine notifies

    20 all the subscribers. The flag provides information on whether a backup or

    21 restore operation is in progress, whether a backup is base or incremental,

    22 and whether the operation is full or partial.</p><p> <codeph>RProperty::Subscribe()</codeph> is

    23 used to subscribe to a flag. The function must be used in conjunction with

    24 an active object to be notified when the value changes. The following category

    25 and key values must be used (defined in <codeph>epoc32\include\connect\sbdefs.h</codeph>):</p> <p>Category: <codeph>KUidSystemCategoryValue</codeph>  </p> <p>Key: <codeph>KUidBackupRestoreKey</codeph>  </p> </section>

    26 <example><codeblock id="GUID-CA14430C-AB7C-5C65-BA41-16FD5A879F9B" xml:space="preserve">#include &lt;e32property.h&gt; 

    27 

    28 RProperty iProperty;

    29 

    30 iProperty.Attach(KUidSystemCategory, KUidBackupRestoreKey);

    31 CActiveScheduler::Add(this);

    32 iStatus = KRequestPending;

    33 iProperty.Subscribe(iStatus);

    34 SetActive();

    35 

    36 // In RunL, to get the state: TInt

    37 backupStateValue = 0;

    38 iProperty.Get(backupStateValue);      </codeblock></example>

    39 </conbody><related-links>

    40 <link href="GUID-796916B2-8B23-5AD8-9DB8-8B0DA7868A62.dita"><linktext>Backup-aware

    41 Software (Data Owner)</linktext></link>

    42 <link href="GUID-743D2832-E73A-5184-A85D-306B2A6FFACC.dita"><linktext>Active Backup

    43 Client</linktext></link>

    44 </related-links></concept>