310600 INT 31 P - DPMI 0.9+ - LOCK LINEAR REGION
310601 INT 31 P - DPMI 0.9+ - UNLOCK LINEAR REGION
310602 INT 31 P - DPMI 0.9+ - MARK REAL MODE REGION AS PAGEABLE
310603 INT 31 P - DPMI 0.9+ - RELOCK REAL MODE REGION
310604 INT 31 P - DPMI 0.9+ - GET PAGE SIZE