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1 <?xml version="1.0" encoding="utf-8"?> |
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2 <!-- Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies) All rights reserved. --> |
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3 <!-- This component and the accompanying materials are made available under the terms of the License |
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4 "Eclipse Public License v1.0" which accompanies this distribution, |
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5 and is available at the URL "http://www.eclipse.org/legal/epl-v10.html". --> |
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6 <!-- Initial Contributors: |
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7 Nokia Corporation - initial contribution. |
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8 Contributors: |
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9 --> |
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10 <!DOCTYPE concept |
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11 PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd"> |
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12 <concept id="GUID-3314123F-205D-5E05-9041-DB9836B7812B" xml:lang="en"><title>File |
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13 Access Example: Accessing the File System Using P.I.P.S.</title><prolog><metadata><keywords/></metadata></prolog><conbody> |
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14 <p>This example application shows, using a P.I.P.S. (P.I.P.S. Is POSIX on |
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15 the Symbian platform) program, the restrictions on file access that are imposed |
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16 by the Symbian platform Security model. </p> |
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17 <p>It shows that programs can access their own directories, but |
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18 cannot, without platform security capabilities not available to ordinary programs, |
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19 access the directories of other programs, or the system binary directory <filepath>sys/bin</filepath>. </p> |
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20 <p>This example defines an executable file with no platform security capabilities. |
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21 The program first creates its own secure directory that it can write to and |
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22 read from. It then attempts to use a file in a private directory of another |
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23 program, and then in <filepath>sys/bin</filepath>, and shows that these attempts |
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24 are denied. </p> |
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25 <section id="GUID-820F9B58-8877-414B-A18B-B591F6D67158"><title>Download</title> <p>Click |
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26 on the following link to download the example: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/zips/guid-2dae3cca-f112-4219-8f7c-6c48682d1f28.zip" scope="external">FileAccessExample.zip</xref></p><p>Click: <xref href="guid-6013a680-57f9-415b-8851-c4fa63356636/guid-2dae3cca-f112-4219-8f7c-6c48682d1f28.html" scope="peer">browse</xref> to view the example code. </p> </section> |
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27 <section id="GUID-3EAFEC43-CFDA-4E3D-8ACD-E3AAE48BE97D"><title>Description</title> <p>The |
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28 following sections provide more information about the steps that the example |
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29 performs. </p> <p><b> Create a secure directory</b> </p> <p>The example creates |
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30 an empty secure directory for the program by using the <xref href="GUID-5EA72F64-E826-3B15-9468-902BD57F6AA7.dita"><apiname>mkdir()</apiname></xref> function. </p> <p>This |
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31 empty secure directory is created in <filepath>C:\private\E80000C9</filepath>, |
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32 as 0xE80000C9 is a unique identifier for the program (as specified by the |
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33 third UID in its project file). </p></section> |
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34 <section id="GUID-D9F306FF-D14E-4BCC-BAE6-55804F31CA0D"> <p><b>Write and read |
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35 a file in the private directory </b> </p> <p>The example writes and reads |
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36 a file in the secure directory using the <xref href="GUID-64886CC6-072F-3542-855A-5D733FC761E8.dita"><apiname>fopen()</apiname></xref> and other |
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37 file stream functions. </p> <p><b> Write and read a file in the private directory |
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38 of another program </b> </p> <p>The example attempts to write and read a file |
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39 in the secure directory of another program. </p> <p>The <xref href="GUID-64886CC6-072F-3542-855A-5D733FC761E8.dita"><apiname>fopen()</apiname></xref> function |
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40 is expected to return <codeph>NULL</codeph>, indicating that access is not |
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41 possible, as the program has insufficient platform security capabilities. </p><p><b> Write |
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42 and read a file in the sys/bin directory</b> </p> <p>The example attempts |
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43 to write and read a file in the system's <filepath>sys/bin</filepath> directory, |
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44 where program binaries are stored. </p> <p>Again, the <xref href="GUID-64886CC6-072F-3542-855A-5D733FC761E8.dita"><apiname>fopen()</apiname></xref> function |
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45 is expected to return <codeph>NULL</codeph>, indicating that access is not |
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46 possible, as the program has insufficient platform security capabilities. </p> </section> |
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47 <section id="GUID-EB4F71F2-D55D-43C5-B55F-F211D170056F"><title>Related APIs</title><p><xref href="GUID-5EA72F64-E826-3B15-9468-902BD57F6AA7.dita"><apiname>mkdir()</apiname></xref></p><p><xref href="GUID-64886CC6-072F-3542-855A-5D733FC761E8.dita"><apiname>fopen()</apiname></xref></p></section> |
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48 <section id="GUID-81AA0C7F-5D43-4EFB-9DD0-4A8A79922576"><title>Build</title> <p>The <xref href="GUID-3100800B-B2F7-50EF-BD4C-3C345ECCB2A5.dita">Symbian build process</xref> describes |
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49 how to build this example application. </p> <p>The example builds an executable |
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50 called <filepath>fileaccessexample.exe</filepath> in the standard locations. </p> <p>To |
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51 run the example, start <filepath>fileaccessexample.exe</filepath> from the |
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52 file system or from your IDE. After launching the executable, depending on |
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53 the emulator you are using, you may need to navigate away from the application |
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54 launcher or shell screen to view the console. </p> </section> |
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55 </conbody></concept> |