On Tue, 19 Jun 2001, Peter Jay Salzman wrote:
> read the source code for a program that reads raw data from an arbitrary
> block device on a level BELOW the filesystem abstraction?
I don't think this is as complicated as you think it is.
> i don't suppose you want to do this for me, eh?
Yeah, I do this sort of thing all the time. There's nothing to it. All
you are doing is reading raw data. You aren't committing anything to the
disk. You're going to, more than likely, just see an open to a device
file, then some system call which effectively performs a read of data.
To extract the meaning of those parameters you are talking about, you are
probably just going to trace out their usage and see how they affect/work
with the I/O operations to the device file. Somewhere along the line,
you'll also seem some basic, higher-level file i/o code that will take the
data retrieved through the system call, and commit it to a file on disk.
And, of course, who knows, maybe the parameters are all documented nicely
in the comments of the source code.
If you really really want to know how it works, I'll explain it.
--
Pavan Tumati ([EMAIL PROTECTED]) http://www.students.uiuc.edu/~tumati
Computer Engineering Student University of Illinois @ Urbana-Champaign
"[...] the problem is almost certainly with your OS, not with the kernel."
- Peter J. Salzman, former chair of Linux Users Group of Davis, CA
(LUGOD), assisting youngsters on proper Linux kernel recompilation.
