Symbian3/SDK/Source/GUID-F4BD69B6-008E-51DB-ABFF-1E17E10B053F.dita
author Dominic Pinkman <dominic.pinkman@nokia.com>
Fri, 11 Jun 2010 12:39:03 +0100
changeset 8 ae94777fff8f
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permissions -rw-r--r--
Week 23 contribution of SDK documentation content. See release notes for details. Fixes bugs Bug 2714, Bug 462.
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<?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 concept
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  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
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<concept id="GUID-F4BD69B6-008E-51DB-ABFF-1E17E10B053F" xml:lang="en"><title>How
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to use sessions efficiently</title><shortdesc>This topic describes how to use file server session effectively.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
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<p>For most purposes, it is not necessary for the user of the file server
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to be aware that it is implemented in a client-server architecture. However,
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for some purposes, you can make your programs much more efficient if you are
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aware of the implications of client-server interaction. </p>
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<p>Essentially, you gain efficiency by using as few as possible client-server
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calls. The main technique for achieving this is to transfer more data with
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each file server function call. Things to watch out for include: </p>
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<ul>
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<li id="GUID-FD15653A-9127-5665-A572-C45B95705D93"><p>Data transfer: use a
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large buffer, and then read bytes from the buffer. The main data-transfer
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clients of the file server all operate through the stream store and the relational
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database. Buffering has been highly optimized for these two components. Therefore,
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application programs using these components automatically gain the maximum
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efficiency in data transfer, without needing any explicit optimization. </p> </li>
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<li id="GUID-52E7009A-368B-5596-AD14-D5C493119472"><p>Reading directories </p> <p>There
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are functions to read a single directory entry at a time, but it is often
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more useful to read multiple directory entries from the server and then to
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scan through them client-side. </p> </li>
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<li id="GUID-4E5A5D73-018B-5ED9-8B3C-5968F40F07C7"><p>Large-scale copying,
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moving and other file management operations </p> <p>A single class, <xref href="GUID-82CEC14F-1479-3922-846A-9FCDB6465EF7.dita"><apiname>CFileMan</apiname></xref>,
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provides high-level function for this, involving only a small number of client-server
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calls. </p> </li>
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</ul>
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<p>The <xref href="GUID-F673F02A-AC5B-3D0F-8D14-21E6221E5015.dita"><apiname>TParseBase</apiname></xref> hierarchy of classes, for analyzing file
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names, operates without client-server interaction. </p>
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</conbody></concept>