<?xml version="1.0" encoding="utf-8"?>+
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<!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. -->+
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<!-- This component and the accompanying materials are made available under the terms of the License +
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"Eclipse Public License v1.0" which accompanies this distribution, +
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and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". -->+
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<!-- Initial Contributors:+
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    Nokia Corporation - initial contribution.+
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Contributors: +
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-->+
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<!DOCTYPE task+
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  PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">+
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<task id="GUID-C4C8395E-F982-4D6A-88D3-28EDC494817F" xml:lang="en"><title>Requesting+
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RAM Asynchronously</title><shortdesc>This section describes how an application can request for free+
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RAM asynchronously.</shortdesc><prolog><metadata><keywords/></metadata></prolog><taskbody>+
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<prereq id="GUID-6C258B11-CE78-42F2-828D-E9C68598C193"><p>Perform the steps+
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described in <xref href="GUID-50CA5439-29A1-426C-83BA-EC048FE86CDE.dita">Allowing+
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Large Memory Allocation</xref>.</p></prereq>+
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<context id="GUID-D36C0590-A436-458B-B7A6-F2E8577E26C6">       <p>Requesting+
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free RAM asynchronously is recommended as the application is not blocked during+
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the method call handling.</p>     </context>+
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<steps id="GUID-4DD07DEC-6017-4237-BE46-1D69E5FBD744-GENID-1-12-1-12-1-1-9-1-5-1-6-1-6-1-5-1-3-3">+
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<step id="GUID-9A69E5AD-E938-4092-A8C2-CB65C37C8962-GENID-1-12-1-12-1-1-9-1-5-1-6-1-6-1-5-1-3-3-1"><cmd>Start an asynchronous+
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request for a block of memory.</cmd>+
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<info><codeblock xml:space="preserve">CMemoryAllocatingObject::StartFunctionalityRequiringAllocationL()+
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    {+
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    User::LeaveIfError(iOomMonitorSession.Connect());+
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    iMemoryRequester = CMemoryRequester::NewL(iOomMonitorSession, *this);+
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    iMemoryRequester-&gt;Start(KLargeValueToAllocate);+
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    }+
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</codeblock></info>+
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</step>+
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<step id="GUID-9A69E5AD-E938-4092-A8C2-CB65C37C8962-GENID-1-12-1-12-1-1-9-1-5-1-6-1-6-1-5-1-3-3-2"><cmd>Implement the active+
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object and request for free memory.</cmd>+
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<info><codeblock xml:space="preserve">void CMemoryRequester::Start(TInt aBytesRequested)+
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    {+
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    iOomMonitorSession.RequestFreeMemory(aBytesRequested, iStatus);    +
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    SetActive();+
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    }+
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</codeblock></info>+
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</step>+
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</steps>+
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<example><p>The following code snippet illustrates an asynchronous request+
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for free RAM allocation: </p><codeblock xml:space="preserve">const TInt KLargeValueToAllocate = 2097152; //2MB+
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+
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// Start an asynchronous request for block of memory+
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CMemoryAllocatingObject::StartFunctionalityRequiringAllocationL()+
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    {+
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    User::LeaveIfError(iOomMonitorSession.Connect());+
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    iMemoryRequester = CMemoryRequester::NewL(iOomMonitorSession, *this);+
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    iMemoryRequester-&gt;Start(KLargeValueToAllocate);+
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    }+
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+
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// Called when the asynchronous request is completed+
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CMemoryAllocatingObject::MemoryRequestCompleteL(TInt aResult)+
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    {+
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    if (aResult == KErrNone)+
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        {+
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        DoFunctionRequiring_KLargeValueToAllocate_BytesL();+
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        }+
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    iOomMonitorSession.Close();+
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    }+
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The active object implementation is the following:+
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+
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// Start an asynchronous request for block of memory+
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void CMemoryRequester::Start(TInt aBytesRequested)+
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    {+
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    iOomMonitorSession.RequestFreeMemory(aBytesRequested, iStatus);    +
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    SetActive();+
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    }+
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    +
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+
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// Called when the asynchronous request is completed+
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void CMemoryRequester::RunL()+
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    {+
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    iObserver.MemoryRequestCompleteL(iStatus.Int());+
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    }+
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</codeblock></example>+
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</taskbody><related-links>+
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<link href="GUID-CE308C71-D8B2-43B3-97FD-B868285ED5FB.dita"><linktext>OOM Monitor+
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Priority</linktext></link>+
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<link href="GUID-39A8FBC9-5FD6-4F92-B71E-5C5438ECFD46.dita"><linktext>OOM Monitor+
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Overview</linktext></link>+
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<link href="GUID-88752800-83BD-4845-80A0-6B65D8D81924.dita"><linktext>OOM Monitor+
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Reference</linktext></link>+
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</related-links></task>+
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