Intern had no idea what not to do, so nearly mangled a mainframe
- Reference: 1759127413
- News link: https://www.theregister.co.uk/2025/09/29/who_me/
- Source link:
This week, meet a reader we'll Regomize as "Benedict" who shared the story of the summer internship he endured many years ago.
"I worked at a big corporation running on mainframes, in the stone age when using a computer meant writing jobs on punched cards and submitting them to be executed," Benedict reminisced. "Our usual job involved working on source files with a batch editor which interleaved commands to skip, modify, insert, and delete new lines into our program."
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Then as now, interns tried to impress their temporary employers in the hope of landing a job offer.
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Benedict therefore read IBM's documentation for the batch editor and, in a fit of youthful enthusiasm and hubris, decided he could improve it.
"I wrote some clever commands, probably something like a search and replace which was pretty spiffy back then," he wrote.
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But Benedict didn't know that some of the full-time staff had already modified the behavior of the batch editor with custom extensions. His code therefore overwrote many files.
"The manual didn't say that could happen," Benedict said. "And there was no manual for the extensions."
[5]Bored developers accidentally turned their watercooler into a bootleg brewery
[6]After deleting a web server, I started checking what I typed before hitting 'Enter'
[7]Playing ball games in the datacenter was obviously stupid, but we had to win the league
[8]I was a part-time DBA. After this failover foul-up, they hired a full-time DBA
Despite this error not being entirely Benedict's fault, his summer employer banned him from using the batch editor, which rather put a dampener on the internship.
He nonetheless persisted with attempts at proactivity by doing things like loading and unloading tapes, and typing simple commands into the mainframe console to prepare it for real jobs.
"When they noticed that, they were horrified at the magnitude of risk I posed, and banned me from that too," he lamented.
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But then he looked at the upside.
"They were still paying me and the summer was glorious," Benedict told Who, Me? "And at the exit interview before I went back to school, the manager said I had finished more tasks than they expected."
Benedict never worked for this very large company again but does celebrate what he learned from it.
"The experience did not cure me from adventurous programming, fortunately," he told Who, Me?
What did you break, or almost break, as an intern? [10]Click here to send us an email so we can share your story in a future edition of Who, Me? ®
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[6] https://www.theregister.com/2025/09/15/who_me/
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Re: "horrified at the magnitude of risk I posed"
Sounds like they got Eggs Benedict on their face though...
Expensive Lessons
When you've paid for an expensive lesson (you being the corporation), it's really a waste to throw that value away by not using the person for the things they've learned.
I never hold back. Someone on my team makes an expensive mistake, and I *know* they won't be making that mistake again. Someone new might. (Maybe we need better training materials.. better guard-rails on our systems, perhaps. Expensive lessons.)
Re: Expensive Lessons
"Sorry Son, but you'll never make Senior Management with that attitude..."
Senior management thinking:
- All workers are interchangeable.
- Someone must be responsible for every mistake.
- All mistakes must be punished.
- If a problem isnt going to affect this quarter's company profits, it's solution can be put off until next quarter (ad infinitum).
Re: Expensive Lessons
"Maybe we need better training materials"
Training materials are expensive, not having training materials can be much more expensive.
(Disclosure: I write training materials, though currently for the heavy lifting industry rather than IT. Talking of crashes, some years ago folks at a nuclear power station decided they could lift a 400 t piece of kit themselves, only they got it wrong and dropped it on top of the reactor. Amazingly, no serious damage (though probably some clean trousers needed). Those lifting operations are now done by one of my customers, using procedures I wrote, No crashes, so far.)
Angle Park
In the mid-70s a select group of secondary students descended on Angle Park Computing Centre where we could run batch jobs with ab turn around measured in minutes instead of days, and where there were two or three interactive terminals, which we shared in something like 30 minute turns. Such joy.
The machine, an IBM 370, mostly ran APL, and as I recall would crash fairly frequently. Oh, APL, you language of )commands.
One time, it was my turn on a terminal when the system was brought back up after a crash. I would have been 15, and showing off, I called friends to gather around while I typed )crash. Hah hah, so funny, except it didn't respond with invalid system command, it sat there thinking for a minute.
Yes, about a minute, that being how long it took the system operator to find out which terminal, race out of the machine room to my terminal, and look at my screen.
I guess the systems programmer wanted to test a crash recovery process so made )crash cause one. Who knew?
⍎A←'⍎A'
Somewhat lacking in detail...
Possibly one of the least-informative and functionally-dubious Who, Me? s there has been.
What was this IBM mainframe "batch editor" of which Benedict speaks? And for which IBM operating system?
And what were the "simple commands [he typed] into the mainframe console to prepare it for real jobs"? I can't see any self-respecting computer operator of the time letting anyone do something like that to 'their' mainframe.
I detect the sound of the bottoms of barrels being scraped...
MVS OS/360 - Almost certainly
It won't have been MTO as this has an on-screen editor rather than a batch edtor.
It could have been VM/CMS, but why would you run in batch on the console if you could run in a VM.
So I am guessing MVS OS/360. That definitely has a console mode with a batch editor, and made heavy use of tapes in a time when disk space was ridicululously expensive.
Ahh, thoe were days. Who can forget PRGM=iebgenr dd-in=TAPE01 dd-out=TAPE02
"horrified at the magnitude of risk I posed"
What? Loading and unloading tapes? Really? Why the hell did they hire him, then?