Just think of it as interactive debugging

It's the early 1970s, and students in this university engineering course write their Fortran programs on paper, have them punched onto cards and then hand the decks in to be run, says a pilot fish who was there.

"I was working on a difficult assignment: calculating the area under a curve using Simpson's Rule," fish says. "By putting print statements throughout the code, the student could easily debug the program.

"The problem was that we were charged for however much CPU and printer time was used. Those debugging statements cost printer time and paper, and if too many debugging lines printed, it really added up."

Fish learns that the hard way. The first run of his program results in a six-inch stack of paper -- and a giant bill to pay.

But he's noticed that a lot of students seem to congregate around a window that looks into the computer room where the mainframe and its related machines live. He assumes that's just because these are engineering students, so seeing a state-of-the-art computer that takes up a whole room is cool.

He's also noticed that a lot of students aren't collecting giant printouts, so he asks around.

Turns out the students at the window aren't just gawking at the Big Iron -- they're actually watching for their jobs to be run. And if the printer spits out more than the few pages they're expecting, they knock on the window and tell the computer operator to kill the job, knowing they've made a mistake.

"I guess after paying one whopping bill, they learned quick how to kill a running job the hard way," says fish.

"The next semester, our instructor taught us how to put exits into our programs to minimize costs."

Keep Sharky up and running by sending me your true tales of IT life at sharky@computerworld.com. You'll snag a snazzy Shark shirt every time I use one. Comment on today's tale at Sharky's Google+ community, and read thousands of great old tales in the Sharkives.

Get your daily dose of out-takes from the IT Theater of the Absurd delivered directly to your Inbox. Subscribe now to the Daily Shark Newsletter.

How AI will change enterprise mobility
Shop Tech Products at Amazon