ot leave blocks locked for extended periods as this may interfere with heap compaction.</P>
<P>
When a process wants to use a block, it instructs the memory manager to lock the block by calling <CODE>
MemLock()</CODE>
 (see <A HREF="Memory_9.htm#70173"> MemLock() locks a block on the heap. It is passed the handle of the block; it returns a pointer to the start of the block on the heap. If the block has been discarded, MemLock() returns a null pointer.</A>
). The application passes the handle of the block, a