QuickBASIC is very similar to QBasic since the latter is just a stripped down version of the former. It had a few functions QBasic did not have — such as the ability to compile programs and libraries, allowed for more than one module, and could create programs which were larger in size. It also had this annoying bug where the memory management model in the interpreter was different than the one used by the compiler; this was a problem when your program worked in the debugger, which used the interpreter, but not when the program was actually compiled and run from the shell.

QBasic shipped with MS-DOS 5 and consisted of only an interpreter, meaning it translated small chunks of code into machine code as they were executed (I believe it did cache the translated portions, so it wouldn’t need to translate them again). QuickBASIC was more advanced and had a compiler as well as an interpreter, which allowed it to translate and optimize the machine code it generated before you ran it. It had only one dependency during compilation, and that was the QB.LIB library. Using the QuickBASIC IDE or the command line, you could compile multiple modules into a single target which could be a library or an executable program.

QuickBASIC was handy for prototyping and demos. I didn’t need to do many of these for my own projects; although, I did a lot of experimentation with network interrupts before porting those routines and programs to C. QuickBASIC was mainly used for projects and demos at school and eventually college; many of them were also written in C due to a few course requirements.

While in college, I had written a chat application over a local area network for DOS before the concept became popular. It was using the SPX protocol for some parts, and the IPX protocol for others. It only supported peer-to-peer communication and only with one other person, bit it served as a demo for simple network communication, and many of the students used it quite regularly.

In other programs, I was using Novell Netware interrupts for communication, broadcasts and client machine discovery. I loved it and found coding these applications fun and exciting; my Ralph Brown textbook was well used during this time. I think my interest in programming these network applications stemmed from my days playing DOOM over similar networks. Basically, I just loved lot the potential for interactivity, which is a tad ironic since I was fairly quiet programmer back then. A few of my friends became interested in the software I was writing and one day I decided to play a few practical jokes on my fellow students. I created a custom program for sending messages via the Netware API. These messages could be broadcast to every machine on the network, a group of machines, or a specific machine. When a machine received one of these messages, it would display a dialog and show the user a message. Pretty simple concept, but many people were not aware their machines could even do that, or what it meant to even be on a network.

Simply using the network software which came with Netware wasn’t an option, since the message dialogs produced by those tools contained the name or address of the machine from which the message originated. According to Steve Wozniak, co-founder of Apple Computers and well-known prankster, the most important element to any gag is not to get caught. We needed to customize the message being sent so that it included only the details we wanted to send, and the only way to do that was to write a custom program. This was fairly easy since I had been writing software on Netware for several months, and when the packets were sent off through the network, our machine name was carefully omitted and our address forged.

We used the program to send funny or confusing messages to some of the students. No profanity or crude humour, mind you… well nothing too crude anyway. My goal was always to get the user to believe what the machine was telling them. I had convinced one student her computer didn’t like the way she typed; her keystrokes were always too hard or fast for the computer’s liking. Several computers were being used by students to view pornography, so I did my best to make them feel uncomfortable in a public setting. Many of them believed they were being watched by the network administrators, which could have been true, although network monitoring software was much more limited at this time). Anyway, these people quickly shuffled out of the room red-faced, hoping not to get caught on their way out. I still get a chuckle out of it even now, when I think about it.

In a way, I am kind of saddened by the complexity of today’s operating systems. Trying to write the same software on modern machines would be extraordinarily more difficult today, mostly because of new operating system and network security features. They just aren’t managed in the same way anymore, so a programmer’s ability to exploit a network so directly has disappeared. I don’t particularly disapprove, it’s just not as easy to have a little fun.

Categories: PC, Reflections
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