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

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

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     7     Nokia Corporation - initial contribution.

     8 Contributors: 

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    10 <!DOCTYPE concept

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

    12 <concept id="GUID-4F882837-0DA1-5243-BA7B-696B418A160E" xml:lang="en"><title>How to

    13 use a package buffer</title><shortdesc>Explains how to use <codeph>TPckg&lt; &gt;</codeph>.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <p>The following code fragments show an object or a C type struct being written

    15 to a file:</p>

    16 <codeblock id="GUID-852DE4D2-DF5B-50BD-B347-627809FBFA22" xml:space="preserve">TXxx x;                    // some structure

    17 TPtr8 xDes(&x, sizeof(x)); // descriptor of that structure

    18 file.Write(xDes);          // write structure to file</codeblock>

    19 <p>While this approach works, it is not type safe. The descriptor could be

    20 mistaken as referring to an object which is not of type <codeph>TXxx</codeph>.</p>

    21 <p>Use a package buffer which works in a similar way but enforces type safety,

    22 as the following code fragment shows:</p>

    23 <codeblock id="GUID-7EBF5473-C9C8-5056-AEFA-6B3CC8822765" xml:space="preserve">TXxx x;                    // some structure

    24 TPckg<TXxx> xDes(x);       // make into a package

    25 file.Write(xDes);          // now write structure t file</codeblock>

    26 </conbody></concept>