DOS under Xenix

[John Tompkins]

I am interested in running DOS programs under UNIX, probably Xenix,  on a
386 machine using something like VP/IX. I was told by the SUN salesman, whose
386i will also run DOS, that programs using a lot of interrupt driven IO
will run slowly. They say it will be faster in the future but there is a lot
of overhead in the interrupt emulation. Does anyone have experience in 
using interrupts driven IO on any of the DOS emulators for UNIX/Xenix ? I am
looking at about 9600 baud on a serial port and maybe some type of DOS
networking on ethernet or arcnet. Thanks in advance.

John C. Tompkins