There are those that persist in writing DOS/Windows applications,
often leaving their customers no other choice but to maintain some sort
of DOS capability in order to run this particular software. Particularly
well known sinners in this respect are banks, for electronic banking applications.
I must say that to my joy the Dutch RaboBank has recently brought electronic
banking to the Internet for its customers, allowing me to ditch their DOS
EB-application. I pray other banks follow soon (especially ABN AMRO since
I am a customer there as well (6 accounts!)).
Another company that insisted in thrusting a DOS application on me is
KPN TELECOM, the Dutch telecommunications monopolist (non-mobile, for all
practical purposes though the market has theoretically opened up for other
competitors as well). When we moved to our new house last year, we bought
a KPN Telecom ISDN/2-8+ telephone switch to handle internal and external
telephone traffic. The switch can be programmed in two ways: through a
DOS application (centrale.exe) or through the main ISDN telephone. This
last option is incredibly complex and kind of boils down to reprogramming
the switch's microcode by entering the binary values of the processor's
machine language on the keypad of the telephone. The DOS application is
not particularly brilliant, but a lot easier to handle.
I had initially programmed the switch using the old "Jadzia" laptop
when it still ran Windows NT. You connect a serial port to the switch,
fire up "centrale.exe" and start interacting with the various configuration
screens. The configuration program has features to upload and download
configurations to and from the switch through this serial connection, but
can store complete configurations locally as well (for backup purposes).
Since my complete switch to Unix (Linux), I had not felt it necessary to
configure the switch, but, for some reasons I won't delve into, that had
changed.
So I had to reconfigure my home's telephone switch. Using the
archaic configuration method (using telephone keys) still did not seem
like a viable option, so I decided that I would have to run the DOS configuration
program. Obviously I could have made life easy by creating a DOS floppy,
boot my portable from floppy and run the "centrale.exe" program from that
floppy. Or, even easier, I could have used my wife's laptop, which still
runs Windows 95. But, I am always one for a challenge, and running it under
the Linux DOS emulator seemed much more fun. I had always known about the
"dosemu" package, I had even installed it when installing SuSE Linux on
my laptop. Now obviously the time had come to configure it.
When I am teaching, I always define "emulation" as "the worst of both
worlds, multiplied". Emulating an entire operating system under another
operating system is no mean feat. There are all kinds of things to take
care of, and especially emulation of hardware devices such as disks and
serial ports require special attention. So, contrary to my general approach
to all things IT, I started out by reading the documentation. Amongst others,
there is a quite helpful HOWTO document on the DOS emulator that covers
most things you need to know and do in order to get the DOS emulator running.
