how to install Xenix plus PC DOS on IBM PC hard disk

[Earl H. Kinmonth]

In article <8903030223.AA18546 at decwrl.dec.com> pogoh at zgom21.dec.com writes:
>I would like to have Xenix & DOS coexist on the hard disk of an IBM PC
>XT compatible.  Can someone tell me in detail how to install the two
>OS on the hard disk?  What must we do upon booting up for the first time

I did this a number of times with an ATT 6300.  The basic trick is to
follow the manual.  Do the DOS side first.  Use fdisk to set up your DOS
partition, then do Xenix.  The only real nastiness, as I remember, is
ambiguity in the instructions.  If you screw up or decide you want to
change sizes and have done at least part of the Xenix installation, use
the Xenix fdisk command to delete the Xenix partition.  Then, start over.
If you do not do this, msdos fdisk cannot change the partition size.

>and how do we switch from DOS partition to Xenix partition & vice versa?

This is explained fairly coherently in the documentation.  When running
Xenix, you have two alternatives:

(a)	as root run fdisk, make the dos partition active, haltsys,
	hit any key;

(b)	insert a bootable msdos floppy, haltsys, hit any key.

>From msdos, use fdisk to make the xenix partition active, use alt-ctl-del.

>Can 'FDISK' on the DOS be used to create & format the partition for Xenix?

NO.

Recent versions of SCO Xenix allow you to haltsys, hit a key, and type
dos to reboot under MSDOS.  Since I no longer use the 8086 version and
do not have updates, I cannot tell you whether this feature has been
added.  It is in the 80286 versions.