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<!DOCTYPE concept

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

<concept id="GUID-C549EC51-D81F-5AEC-80EA-EF83B2D9AF51" xml:lang="en"><title>Structure

of a heap</title><shortdesc>A heap consists of two lists of cells; the list of allocated cells

and the list of free cells.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>

<p>A heap simply consists of two lists of cells; one is the list of allocated

cells and the other the list of free cells. Each list is anchored in the heap

object.</p>

<p>A cell consists of a cell header followed by the body of the cell itself.

The body of the cell is the area of memory which is considered allocated.</p>

<p>The cell header is a struct of type <codeph>RHeap::SCell</codeph> defined

as part of the <codeph>RHeap</codeph> class in <filepath>e32std.h</filepath>.</p>

<p>The following diagram shows a typical mix of free and allocated cells.</p>

<fig id="GUID-A066C7F2-B6E9-5F64-8A00-F2AC5D16B585">

<title>Example of the allocated and free cells in a heap</title>

<image href="GUID-4B4110D9-0CAA-5CA1-A994-9DAF501119E4_d0e240294_href.png" placement="inline"/>

</fig>