C programming question

[Peter L. Peres]

On Fri, 19 Dec 2003, Jim Skehill wrote:

> If you are programming in C you can go down to the assembler level and issue
> a BIOS interrupt (sorry I don't recall the number) to write to a particular
> disk location.
> DOS interrupt 25H allows you to write to a particular disk sector, but
> seeing that this is the TLUG Mailing list, I don't imagine that's of much
> help to you.

Except you can't do that in linux since the bios is not functioning while
in linux. There are equivalent functions in the kernel, not available from
user space. In theory you can acheieve the same effect by using the raw
device (e.g. /dev/hda) and use (f)seek & co. to acceess a physical sector
(which you get to compute using the disk geometry). You have to be root to
do this and the potential for problems is enormous.

Peter
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