Msdos hidden files viewable from linux?

Mark J. Dulcey mdulcey at pryder.pn.com
Wed Oct 25 23:48:26 EDT 1995


On Wed, 25 Oct 1995, Albert Cahalan wrote:

> Note that it is _impossible_ to correctly backup and restore DOS system
> files without low-level disk access (read: dangerous).  The system bit
> means that the file is sensitive to it's physical position on disk.
> As far as I know, you can't back up and restore /boot or the kernel
> either, because lilo gets confused.  The same goes for msdos.sys and
> io.sys.  Maybe someone could write a program to fix the boot sector to
> point to these files.

Actually, the DOS system files are no longer position-sensitive in DOS 5 
and later.  The only thing special about IO.SYS and MSDOS.SYS is that 
they must be the first two files listed in the root directory; they can 
be stored anywhere on the disk.  DBLSPACE.BIN has no special requirements 
at all.

If you restore IO.SYS and MSDOS.SYS to a completely empty disk, they will 
automatically go into the required places in the directory.  Otherwise, 
you need low-level access to put them back.  It's simpler to just put 
them back with the SYS command from a DOS floppy if needed.

386SPART.PAR (Windows permanent swap file) IS position-sensitive; it 
must be in the place that /WINDOWS/SPART.PAR says it is supposed to be, 
or you get a "corrupt swap file" message when you start Windows.  
386SPART.PAR also must be in contiguous disk sectors; it can't be broken 
up by other files or bad sectors.



More information about the Discuss mailing list