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View Full Version : Can any Windows OS prevent unauthorized I/O?



Dinosaur
02-14-2003, 06:27 PM
The Turbo Tax installation process writes some data to unused sectors on the track containing the Partition Table. This is part of an anti-piracy scenario to prevent use of the same version of Turbo Tax on multiple systems.

I assume that machine language level I/O is required to write to that track.

In the mainframe world, it is almost impossible to issue machine language I/O from an application program. I/O commands cause interrupts, allowing the OS to monitor and prevent unauthorized I/O. A hacker would have to put a patch in the OS before it was loaded to get around this restriction.

Can an application program under Windows issue machine language level I/O?

Paul Komski
02-14-2003, 10:51 PM
I guess that peek and poke (as in old basic) can do this with an application such as at this link:- http://www.zealsoftstudio.com/memaccess/

... or maybe I'm just having delusions ... LOL ... thats RAM of course.

Might however be some currency in using WinHex (http://www.sf-soft.de/winhex/index-m.html) "The Disk Editor, that is part of the Tools menu, enables you to access floppy and hard disks below file system level. Disks consist of sectors (commonly units of 512 bytes). You may access a disk either logically (i. e. controlled by the operating system) or physically (controlled by the BIOS). On most computer systems you can even access CD-ROM and DVD media."