INT 67H 5c00H: Prepare for Warm Boot

                                                     Compatibility: EMS 4.0+ 
 Expects: AX    5c00H
          ──────────────────────────────────────────────────────────────────
 Returns: AH    EMM status (0=successful)
          ──────────────────────────────────────────────────────────────────
    Info: This is designed for use by operating systems only and may be
          disabled at any time.

          This fn warns the EMM that the system is about to reboot.  A very
          few hardware-based EMS implementations can maintain valid data
          across a warm boot.

          See INT 67H 52xxH (get/set handle attribute).

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