[net.micro.pc] PC/XT Help Needed

maciag@spar.UUCP (Chris Maciag) (02/08/85)

I am currently running MS-DOS and PC/IX (a bad copy of Unix System 3) on
an IBM XT.  Unfortunately, PC/IX can only be loaded from the active
partition.  I would like to be able to run a program from MS-DOS that
would bring up PC/IX, and vice-versa if possible (either way will be
extremely helpful).  To do this, I need to:

Read sector 0 of the fixed disk (C:)
change the 10th byte of the sector to
Write the the sector back (with change)
Reboot Fixed Disk (not a neccessity)

It would be good if this could be done independent of MS-DOS, that way I
could use the same routine, with a few changes, to get back to MS-DOS.
Any help you can give me will be greatly appreciated.

		Chris Maciag

johnl@ima.UUCP (02/09/85)

When I wanted to switch from PC/IX to DOS, I used regular Unix adb to patch
block 0; just adb -w /dev/hd8 (which is the whole disk) and patch location 10,
then run shutdown.  It's easily packaged up as a shell script.

MS-DOS being a much worse version of Unix than PC/IX, I suspect there's no way
around writing a little program that makes the patch.

John Levine, ima!johnl