INT 67H 4d00H: Get Page Information For All Handles

                                                     Compatibility: EMS 3.2+ 
 Expects: AX    4d00H
          ES:DI buffer to receive return information
 Returns: AH    EMM status (0=successful)
          BX    count of active handles
          ES:DI buffer contains (BX*4) bytes of data
    Info: Returns the size of allocations for all currently-open EMM

    ES:DI on entry, the buffer at this address should be large enough to
          hold the returned data.  You need 4 bytes for each handle.  Use
          INT 67H 4c00H to see how many handles exist.

          On return, this buffer contains BX entries in the form:

           Offset Size Contents
           ▀▀▀▀▀▀ ▀▀▀▀ ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
            +0      2  wHandle    the handle number
            +2      2  wAllocdPgs size of allocation, in 16K units
                    4             size of one record

See Also: INT 67H: EMM Services
          Extended Memory Specification (XMS)
          Interrupts and BIOS Services