cur022%cluster@ukc.ac.uk (Bob Eager) (04/11/91)
In article <28023A20.23271@orion.oac.uci.edu>, ece134@venice.eng.uci.edu writes: > I was wondering if "diskcopy" copies all bytes of all sectors > (9 on 360K floppy disk, 15 on 1.2M floppy) on the first 2 tracks > (track 0 and 1). I have the believe that certain bytes are > not copied. Could anyone tell me > a) if I am right or wrong > b) what bytes are not copied (in case I am right) DISKCOPY will copy all bytes of all sectors as specified, unless you are using DISKCOPY on DOS 4.x or OS/2. On these systems, it does not copy the eight bytes immediately before the bootstrap code in the very first sector. You can locate these by looking at the boot sector with DEBUG, and finding the destination of the JMP instruction at the front. Eight bytes immediately preceding this jump destination are the disk serial number and are meant to provide a measure of uniqueness to cut down on mistakes when disk swapping (e.g. during a single-drive copy). It is possible that earlier OEM versions of DOS do this trick too. -------------------------+------------------------------------------------- Bob Eager | University of Kent at Canterbury | +44 227 764000 ext 7589 -------------------------+-------------------------------------------------