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    10 <!DOCTYPE concept

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

    12 <concept id="GUID-AB705D21-87A3-5F32-A4B9-17B7593DD5C3" xml:lang="en"><title>UID

    13 Manipulation Overview</title><shortdesc>Describes how globally unique identifiers are manipulated.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

    14 <section id="GUID-78302F5A-97C3-4B95-9F72-842D91C2C25C"><title>Purpose</title> <p>To guarantee uniqueness,

    15 all UID values are assigned to developers centrally by Symbian. </p> </section>

    16 <section id="GUID-0600181A-2383-419B-BB57-2833C05F9AE3"><title>Architectural relationships</title> <p>Symbian platform makes

    17 extensive use of UIDs to provide lightweight identification of file types.

    18 This includes both document and executable files. APIs that need to manipulate

    19 files therefore typically use UIDs.</p> </section>

    20 <section id="GUID-B4652BA6-A500-4F3E-9AFF-02C339706B2B"><title>Description</title> <p>The API has two key concepts: UID and

    21 compound identifier. </p> <p><b>UID</b> </p> <p>The

    22 UID is a small wrapper class around a 32-bit value that provides comparison

    23 operators and conversion to text.</p> <p>The UID interface is provided by <xref href="GUID-530281E6-29FC-33F2-BC9B-610FBA389444.dita"><apiname>TUid</apiname></xref>.</p> <p><b>Compound identifier</b> </p> <p>The compound identifier is a group of

    24 up to three UIDs that identify the type of a file. The meaning of the UIDs

    25 varies according to whether the file is a DLL, or document file, etc. </p> <p>The

    26 compound identifier interface is provided by <xref href="GUID-B6D6B0AD-B15C-339A-8540-40540885089A.dita"><apiname>TUidType</apiname></xref>.</p> </section>

    27 <section id="GUID-ECF8B994-B8F0-4EC4-8CE8-06F031541D79"><title>See also</title> <p><xref href="GUID-260C7ACD-0024-59DE-B1C6-0C852E44C457.dita">Dynamically

    28 Loading Link Libraries Overview</xref> </p> <p><xref href="GUID-B69FE02E-3A78-5438-BA7C-F7BB4CD3EB76.dita">File

    29 Server Client Side Overview</xref> </p> <p><xref href="GUID-21CF1D5F-44C5-5407-B3C9-8BC103C97079.dita">File

    30 Stores Overview</xref> </p> </section>

    31 </conbody></concept>