Int 31/AX=FF1Fh

AX = FF1Fh ESI = starting application-relative linear address EBX = size of region in bytes

Return:
CF clear if successful CF set on error

Desc: Prevent memory from being swapped out by the virtual memory manager

Note: Locks are applied on 4K page boundaries, so memory above and below the specified region may be locked as well

See Also: AX=FF1Ch - AX=FF20h