Int 31 Fn 0509  P - DPMI 1.0+ - Map Conventional Memory In Memory Block    [E]

   AX = 0509h
   ESI = memory block handle
   EBX = page-aligned offset within memory block of page(s) to map
   ECX = number of pages to map
   EDX = page-aligned linear address of conventional (below 1M) memory

Return: CF clear if successful
   CF set on error
       AX = error code (8001h,8003h,8023h,8025h) (see AX=0000h)

Notes: only supported by 32-bit DPMI hosts, but may be used by 16-bit clients
   support of this function is optional

See Also: AX=0504h,AX=0508h,AX=0801h