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

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     7     Nokia Corporation - initial contribution.

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    10 <!DOCTYPE concept

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

    12 <concept id="GUID-2C7AF56F-F741-5C9B-83B9-46C175330ED1" xml:lang="en"><title>Safe

    13 data access</title><shortdesc>Describes how the parameters that are passed to the descriptors

    14 are checked to ensure the they are not accessing illegal data.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    15 <p>The parameters that are passed to descriptor functions which access or

    16 operate on data, are checked to ensure that those operations are correctly

    17 specified and that no data outside the data area represented by the descriptor

    18 is accessed or changed.</p>

    19 <p>It is the programmer’s responsibility to ensure that all accesses to descriptor

    20 data are within bounds and that descriptors are sufficiently large to contain

    21 their data, either by making the original allocation large enough at program

    22 compile time or by dynamically allocating the descriptor at run-time.</p>

    23 <p>An illegal data access raises an exception, known as a panic, causing immediate

    24 program termination. In this event, it can be assumed that no illegal access

    25 of memory has taken place and that no data has been moved or damaged.</p>

    26 <p>The Format() function which operates on descriptor data is the only case

    27 where a program is offered the opportunity to handle a potential exception.</p>

    28 <section id="GUID-6C0DFCF4-2742-4F07-A161-A1A23879F99F"><title>See also</title> <p><xref href="GUID-445B19E5-E2EE-32E2-8D6C-C7D6A9B3C507.dita#GUID-445B19E5-E2EE-32E2-8D6C-C7D6A9B3C507/GUID-EE7DBF18-A16C-3983-924F-20C1907E7AAA"><apiname>TDes8::Format()</apiname></xref> </p> <p><xref href="GUID-C04A9A0C-DBA7-37DA-B744-54FBF3D544CD.dita#GUID-C04A9A0C-DBA7-37DA-B744-54FBF3D544CD/GUID-F3ED8A38-74C5-3C4D-AEAF-B405A0C5807D"><apiname>TDes16::Format()</apiname></xref> </p> </section>

    29 </conbody></concept>