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<!-- Initial Contributors:+
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    Nokia Corporation - initial contribution.+
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Contributors: +
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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-3829BD20-3DCB-5489-8FC4-07F954E391BF" xml:lang="en"><title>Local+
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and global handles</title><shortdesc>This document explains the distinction between local and global+
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handles.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>+
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<p>This is the issue of Kernel side object visibility.</p>+
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<p>Handles are said to be local or global.</p>+
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<p>A handle is <i>local</i>, if the Kernel object which that handle represents+
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is only visible to the thread that created it; no other thread can open a+
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handle to the same Kernel object.</p>+
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<p>Typically, code constructs the appropriate <codeph>RHandleBase</codeph> derived+
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object, e.g. an <codeph>RMutex</codeph>, and calls its <codeph>Create()</codeph>, <codeph>CreateLocal()</codeph> or+
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equivalent function to create the corresponding Kernel object.</p>+
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<p>A handle is <i>global</i>, if the Kernel object which that handle represents+
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is visible to all threads across all processes; any thread in any process+
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can open a handle to that same Kernel object. Typically, such a Kernel object+
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is intended for sharing.</p>+
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<p>For a global handle. the corresponding Kernel object is assigned a name.+
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The name gives that Kernel object an identity and is the key property which+
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allows other threads to open a handle onto that same object. It is usual to+
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use a <codeph>TFindHandleBase</codeph>  <i>derived</i> class to locate a global+
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Kernel object. The following diagram shows the general idea.</p>+
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<fig id="GUID-01C60CFA-8CA7-51CC-904E-158EC02959DE">+
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<image href="GUID-5398C2DC-9AFA-5517-BCBF-5964970B9656_d0e205824_href.png" placement="inline"/>+
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</fig>+
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<p>See also:</p>+
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<ul>+
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<li id="GUID-56D39619-C90C-51DF-9475-3B75FB189258"><p><xref href="GUID-FC639517-F138-5E84-B57A-6347F5A47B88.dita">Names+
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and fullnames</xref> in reference counting objects.</p> </li>+
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</ul>+
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</conbody></concept>+
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