INT 31 P - DPMIsee DOS Protected-Mode Interface 1.0+ - GET MEMORY BLOCK SIZE AND BASE
	AX = 050Ah
	SI:DI = memory block handle
Return: CF clear if successful
	    SI:DI = size in bytes
	    BX:CX = base address
	CF set on error
	    AX = error code (8023h) (see #03143)
SeeAlso: AX=0501h,AX=0504h