Direct disk access in DOS
I'm writing a small disk utility that will allow the user to view the bootsector, bootstrap, partition tables, FATs, and also browse their drive sector by sector.
I'm using the INT 13 API under Win98SE but Windows is continually blocking my INT 13 calls so that all registers return 0's. I've even issued the Lock Physical Volume INT 21h, subfunction 484Bh, to lock the volume so I can directly access the disk. Still no go. Windows will not even let me get the drive parameters for the drive so it is impossible for me to even do CHS or CHS to LBA translation on the drive.
Does anyone know how to tell Windows to lock the volume so that I can directly access the disk (hard disk - floppies will work). I really need this information and I've done a lot of research but none of the pages talked about this problem.
When I issue Lock Physical Volume to DOS 7.20 I get 0005h in AX which means ACCESS DENIED. I have to tell Windows to take a hike before I can access the drive. Please help.