<?xml version="1.0" encoding="utf-8"?>
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    Nokia Corporation - initial contribution.
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<!DOCTYPE task
  PUBLIC "-//OASIS//DTD DITA Task//EN" "task.dtd">
<task id="GUID-9477D9DC-7B89-4D60-A7DF-B89411379A52" xml:lang="en"><title>Use
Agent-Specific Commands</title><shortdesc>This is an extension mechanism to allow a client to perform an
agent-specific function. The application needs to know the extended commands
that the agent supports and the format of the input and output buffers used
in the command. All of this is specified by the CAF agent, not the Content
Access Framework.</shortdesc><prolog><metadata><keywords/></metadata></prolog><taskbody>
<prereq>       <p>The manager object must be created using the <xref href="GUID-7F3D9E35-A8FC-35A6-8036-23396BAADFDC.dita#GUID-7F3D9E35-A8FC-35A6-8036-23396BAADFDC/GUID-2F4CB027-777F-3F16-AE9A-8902F4AE87E7"><apiname>CManager::NewL()</apiname></xref> function. </p> 
   </prereq>
<steps id="GUID-4DD07DEC-6017-4237-BE46-1D69E5FBD744-GENID-1-10-1-25-1-1-6-1-5-1-5-1-6-1-4-1-6-1-3-2">
<step id="GUID-9A69E5AD-E938-4092-A8C2-CB65C37C8962-GENID-1-10-1-25-1-1-6-1-5-1-5-1-6-1-4-1-6-1-3-2-1"><cmd>The buffers allow
agent specific objects to be externalized by an application, passed through
CAF and internalized by the agent. The same principle applies for data returned
from the agent to the application.</cmd>
<info><codeblock xml:space="preserve">TInt FancyApplicationFunction(CManager&amp; aManager, CAgent&amp; aAgent, CFancyAgentInputObject&amp; aInputObject, CFancyAgentOutputObject&amp; aOutputObject)
    {
    // Buffer large enough to hold the expected output object 
    TBuf &lt;1000&gt; outputBuffer; 

    // Dynamic buffer to serialize aInputObject 
    CBufFlat* inputBuffer = CBufFlat::NewL(50); 
    CleanupStack::PushL(inputBuffer); 
    RBufWriteStream streamIn(*inputBuffer); 
    CleanupClosePushL(streamIn); 

    // write aInputObject to the dynamic buffer 
    aInputObject.ExternalizeL(streamIn); 
    CleanupStack::PopAndDestroy(&amp;streamIn); 

    // Call the agent specific function #42 
    aManager.AgentSpecificCommand(aAgent, 42 ,inputBuffer-&gt;Ptr(0), outputBuffer); 

    // Don't need the input buffer any longer 
    delete *inputBuffer; 
    inputBuffer = NULL; 

    // Create a stream object to read the output buffer             
    RDesReadStream streamOut(outputBuffer); 

    // Build the output object from the output stream 
    aOutputBuffer.InternalizeL(streamOut); 
    }</codeblock></info>
</step>
</steps>
</taskbody><related-links>
<link href="GUID-E99E0092-5F1D-5715-945E-E83C307357C3.dita"><linktext>Managing
CAF Agents</linktext></link>
</related-links></task>