!*** MODULE PAGEDEF ***
!DEC$ OPTIONS/ALIGN=(RECORDS=PACKED,COMMONS=PACKED)/NOWARN
	PARAMETER MMG$C_VAX_PAGE_SIZE = '00000200'X  !  SIZE OF VAX PAGE
	PARAMETER MMG$C_ALPHA_MAX_PAGE_SIZE = '00010000'X  !  MAX. PAGE SIZE
	PARAMETER IOC$C_DISK_BLKSIZ = '00000200'X  !  STANDARD DISK BLOCK SIZE
	PARAMETER IOC$C_CD_DVD_BLKSIZ = '00000800'X  !  Typical CD and DVD sector size
	PARAMETER IOC$M_BLOCK_BYTEMASK = '000001FF'X
	PARAMETER IOC$M_BLOCK_BLKNUM = 'FFFFFE00'X
	STRUCTURE /BLOCKDEF/
	UNION
	    MAP
	        PARAMETER IOC$S_BLOCK_BYTEMASK = 9
	        PARAMETER IOC$V_BLOCK_BYTEMASK = 0	 ! BYTE VIELD 
	        PARAMETER IOC$S_BLOCK_BLKNUM = 23
	        PARAMETER IOC$V_BLOCK_BLKNUM = 9
	        BYTE %FILL (4)				 ! BLOCK NUMBER 
	    END MAP
	END UNION
	END STRUCTURE	! BLOCKDEF
	PARAMETER IOC$M_DVDBLK_BYTEMASK = '000007FF'X
	PARAMETER IOC$M_DVDBLK_BLKNUM = 'FFFFF800'X
	STRUCTURE /DVDBLKDEF/
	UNION
	    MAP
	        PARAMETER IOC$S_DVDBLK_BYTEMASK = 11
	        PARAMETER IOC$V_DVDBLK_BYTEMASK = 0	 !  CD/DVD Vield 
	        PARAMETER IOC$S_DVDBLK_BLKNUM = 21
	        PARAMETER IOC$V_DVDBLK_BLKNUM = 11
	        BYTE %FILL (4)				 !  CD/DVD Block Number
	    END MAP
	END UNION
	END STRUCTURE	! DVDBLKDEF
!DEC$ END OPTIONS