Dos and unix on same Disk

[Christopher Justice]

I'm having a problem installing both AT+T System V R3.2.2 and Dos 4.0 on the 
same disk drive.  I partioned the drive (330 meg) into an 80 meg Dos 
partition and the rest for unix.  They installed succesfully, but Dos gives
me a "General failure reading drive C:" when I try to run programs.  This
happens irregularly.  Unix has given me a couple of "unrequested harddrive
interrupt errors". 

Our computer Vendor is trying to tell us that you can not install unix
and dos on the same drive, or possibly that dos can not take up more than
9% of the drive.  I find this hard to believe.  If Dos and unix are on
different partitions, it shouldn't matter.  

Is using Dos and unix on the same drive common?  Can you do this?  I'd like
to hear about your experience with doing this.

Thank you!

Chris Justice
justicec at cs.colostate.edu
Chris Justice                          
justicec at cs.colostate.edu