A tale of mainframes and students being too clever by far

Behold, the Move of Certain Doom

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Who, Me? Take a trip back to the 1980s with a Monday morning cautionary tale of cleverness, COBOL and mainframe programming in today's Who, Me?

While some who lived through the 1980s remember it as a freewheeling time of Knight Rider, Magnum PI and, er, Worzel Gummidge, for Register reader Sam it was a period of hard work and code wrangling.

In those carefree days Sam could be found working at a bank as well as attending college through a workplace reimbursement program.

"This bank," he recalled, "ran fairly sophisticated and cutting-edge programs to help maintain a financial advantage over competitors."

Many banks did the same, and Sam told us: "There were several very intelligent and innovative programmers who came up with solutions that involved instructing the computer to do things not envisioned by the IBM engineers of the time."

The problem was that Sam's on-the-job education aimed at squeezing every last drop of performance out of big hunks of IBM metal did not sit too well with what was being taught in college.

The wheels finally came off when, having already annoyed his COBOL instructor "through the use of those new-fangled structured programming techniques", Sam was tasked to write some code requiring the use of tables.

The college expected that some looping code would be used to initialise the table ready for use. Sam knew better: "Through my work I had been shown an easy way to do this using a simple move statement."

Far more efficient but, alas, while the bank ran on IBM hardware, Univac ruled the roost at the college, and the machines did not work in quite the same way.

At the bank, the process would have been handled flawlessly. At the college... less so.

"The result," said Sam, "was to continue writing through memory until the operating system itself was overwritten and the mainframe shutdown nearly immediately and without warning."

When the mainframe recovered, the program request list (including Sam's move of doom) was run again. Again, everything fell over.

"Since everything in memory was essentially initialized," he explained, "it made debugging by the college IT staff impossible."

"I was told they had to bring in the computer vendor's team to figure out what was happening."

Sam's co-workers at the bank, who had shown him the trick, were not overly surprised to learn of the borkage. The hardware was incompatible, after all, but Sam was a tad too green to understand the implications.

And his course?

"The college IT administration was not happy. My instructor was even more unhappy since he felt it reflected upon him personally."

"I did not finish that class. I did not continue my education at that college."

Ever rolled out a nifty trick, only to have it explode messily in your face? Or poked a bit of memory that maybe you shouldn't have? Share your experience with an email to Who, Me? ®

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