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-4DAC39E0-2EC2-40F7-9AEF-4FDA09F1A151" xml:lang="en"><title>Asynchronous

    13 Requests</title><shortdesc>This document discusses the use of asynchronous requests by device

    14 drivers.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <p>An asynchronous request is typically used to start an operation on a device

    16 that completes at a later point of time. It returns immediately after starting

    17 the operation on the device or making a request to the driver. The user side

    18 thread is not blocked and can continue with other operations, including issuing

    19 other requests (synchronous or asynchronous). </p>

    20 <p>A driver lists the available asynchronous request types in an enumeration. </p>

    21 </conbody></concept>