The A-Z of geek: D is for DOS

This summer I purchased an IBM PS/1 computer.  This machine was originally released 26 years ago in 1990, the year that the Hubble space telescope was launched; Thatcher was replaced by John Major; Iraq invaded Kuwait; the Channel Tunnel between France and England was completed and Deee-lite released "Groove Is in the heart". 

The IBM PS/1 runs an Intel 80286 processor at 10 MHz and has a massive 1024KiB of RAM.  The system has one 31/2 inch floppy disk-drive and a 40MB hard disk.

...So, prepare to type "cd.." because today...

D is for DOS

DOS is the name for a family of command line disk operating systems popular throughout the 1980s and 90s. My IBM PS/1 runs IBM DOS4.01.

An IBM PS/1 in slightly better condition than mine.

The computer does not run Windows. Instead it has a four-quadrant graphical displaying giving access to a fairly comprehensive system tutorial; MS-Works office tools; file explorer and DOS. The display can be navigated with either the mouse or cursor keys.

The IBM Graphical User Interface.
This machine was designed for home users with little experience of computers, and so everything has been made as simple as possible. In fact, you do not need to know any DOS commands to use the system, but seriously, where is the fun in that?

The IBM has a graphical 'file explorer' program built-in. They have tried to make it look like a filing cabinet, and although it looks great, DOS is much more fun.

The first thing that I needed for my computer was a text editor program to edit bat files.  I chose to use a shareware application called "QEDIT" from SemWare. I then created a bat file in the DOS folder. The bat file contains the following two commands:

c:\utils\qedit\q.exe %1
type %1

The first line is the path to the qedit program which allows an optional parameter. The second line passes the parameter to the qedit program. I then saved the file as "c:\dos\qedit.bat".

This allows me to edit any text file, or create a new text file, by typing "qedit <filename>" from anywhere in the command line.

DOS was really a great system because it allowed you to create as many bat files as you wanted. If they were saved to the DOS folder (or another folder that you could specify in the configuration settings) thus expanding the system's vocabulary.

The second job I did with the IBM was to create a 'help' file to allow me to keep track of all of the user-defined bat files that I was creating.

The help file is accessed by the command 'help' (which, of course, runs the 'c:\dos\help.bat' script), or 'help <topic>' which then gets information about the specified topic.  This is achieved with the following code:

@echo off
ECHO Greeting message
IF %1. == . GOTO showall
IF %1. == helptopic1 GOTO helptopic1
IF %1. == helptopic2 GOTO helptopic2

GOTO end

ECHO SYNTAX: help <topic>
ECHO Help available for the following commands:
ECHO helptopic1, helptopic2, etc
GOTO end

ECHO help provided here
GOTO end

ECHO help provided here
GOTO end

ECHO That's all folks!

Well that's about all I've done with DOS on my IBM PC apart from loading several DOS games, and also playing with the version of BASIC that comes with it.

If you find the need to dust off your DOS computer, then there are a load of DOS games archived on various websites, not least, this one.

So, it's video time.

Here is an IBM PS/1 promotional video, with (hilarious) jab at Apple computers.

IBM PS/1 showing boot-up time.

An IBM running Prince of Persia

An IBM PS/1 running Windows 3.0