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<!DOCTYPE concept
  PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd">
<concept id="GUID-239AA6F5-30CE-5FF0-9C36-93D39FECE1DD" xml:lang="en"><title>How
to switch heaps</title><shortdesc>After a call to <codeph>User::SwitchHeap()</codeph>, any new request
for memory is satisfied from the new heap.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody>
<p>A thread can switch between heaps using <codeph>User::SwitchHeap()</codeph>. </p>
<p>After a call to this function, any new request for memory is satisfied
from the new heap.</p>
<p>When freeing memory, it is <b>extremely important</b> that the current
heap is the heap from which it was allocated. Trying to free a memory cell
from a heap when it was allocated from a different heap has undefined consequences.</p>
<codeblock id="GUID-8265D4CF-CDCE-51EF-AC31-765830961D8E" xml:space="preserve">Thing* mything = new Thing;                // Allocate on current heap
RHeap* oldHeap = User::SwitchHeap(newHeap);// Change heaps
...                                        // Use new heap
User::SwitchHeap(oldHeap);                 // Change to old heap
delete mything;                            // before deleting.</codeblock>
</conbody></concept>