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<concept id="GUID-485B1284-9DB0-5AF7-906A-89A830B9FE44" xml:lang="en"><title>Handles

Overview</title><shortdesc>This document provides an overview of handles.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<section id="GUID-115D8AE7-F04D-47DE-83B4-0F651D721006"><title>Purpose</title> <p>Allows

a thread or process to identify an object which is owned or managed by another

thread or process. Handles allow a client to access, or refer to, Kernel objects.</p> </section>

<section id="GUID-245AC90F-A46C-488E-B4FE-435F93851682"><title>Architectural

relationships</title> <p>All handles are instances of classes derived from <codeph>RHandleBase</codeph>.

Interactions between the holder of a handle and the object which the handle

represents are mediated through the Kernel. Handles are also used in client-server

relations; the client side refers to a server side session through a handle,

an<codeph>RSessionBase</codeph> object.</p> </section>

<section id="GUID-DCBCFDE8-F8BA-455A-8918-0EC26EADE2C8"><title>Description</title> <p>The

handle class, <xref href="GUID-727D2B62-09A9-3CBC-AB6F-591E52EC68EB.dita"><apiname>RHandleBase</apiname></xref>, encapsulates the basic behavior

common to all handles; for example, <codeph>Close()</codeph> to close a handle.

In particular, the class hides the handle-number which identifies the object

which the handle represents.</p> <p>The class is abstract in the sense that

a <codeph>RHandleBase</codeph> object is never explicitly instantiated. It

is always a base class to a concrete handle class; for example, <codeph>RSemaphore</codeph>, <codeph>RMutex</codeph>, <codeph>RThread</codeph> etc.</p> </section>

<section id="GUID-9ABD8697-9E59-44D6-8F2C-4D73A3EF15E9"><title>See also</title> <p><xref href="GUID-BE0C94BE-94F0-54B3-8674-366C09261E5D.dita">Reference Counting Objects

Overview</xref> </p> <p><xref href="GUID-5D4B86D3-20C4-5D87-A6C1-225018D32347.dita">Threads

and Process Management Overview</xref> </p> <p><xref href="GUID-D0D27AEA-FDDB-5F6F-94F6-ADDF5910DC47.dita">Client/Server

Overview</xref> </p> </section>