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─────Run-Time Library───────────────────────────────────────────────────────
 
  Variable:  _amblksiz
 
  Include:   <malloc.h>
 
  Syntax:    unsigned _amblksiz;
 
     The value of _amblksize is used to control how memory is obtained
     from the operating system for the heap. The initial requested
     size for a segment of memory for the heap manager is based on the
     amount of current allocation request plus overhead for the heap
     manager's bookkeeping chores─that is, just enough to satisfy the
     allocation request at hand (for example, a malloc or calloc).
 
     However, when the heap manager grows a segment, it does so in
     multiples of _amblksize. The value of _amblksize represents a
     trade-off between the number of times the operating system must
     be called to grow a segment to its maximum size (no more than
     640K for DOS) and the amount of memory potentially wasted
     (available but not used) at the end of the heap.
 
     The default value of _amblksize is 8K. The value can be changed
     by direct assignment in your program. For example:
 
          _amblksize = 2048;
 
     The actual value used internally by the heap manager will be the
     given value, rounded up to the nearest whole power of 2 (so an
     _amblksize value of 4K-1 is the same as a value of 4K).
 
     Note that adjusting the value of _amblksize affects allocation
     in the near, far, and based heaps. The value of _amblksize has
     no effect on huge memory blocks (those allocated with _halloc
     and similar functions).
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