I just found out the creator of Windows Task Manager accidentally left his phone number inside the app

Whenever I think of old-school programming, I think of people like Dave Plummer, the creator of the original Task Manager. Working for Microsoft in the 1990s, he built that app, which we now very much take for granted, brick by metaphorical brick. That isn't to say there was zero hackiness involved—far from it, as with much pre-2000s code.

Case in point is something I just learned about the original app: Plummer accidentally left his phone number inside it. "It's one of those tiny bits of old code that tells a story," he says.

It all started by him noticing, when developing the original app, that CPU utilisation was sometimes adding up to over 100%, which is "just not possible if the math is being done right."

After checking the math was right on his end and finding nothing wrong, the other possibility was that there was a bug in the kernel, as that's where the data was being pulled from. But it was difficult to get any of the kernel developers to take this idea seriously in part because of the "pecking order" at Microsoft in the '90s: "the kernel is where the silverbacks live."

"I was just a UI guy drawing little pictures of CPU usage. So, as you can imagine, when I proposed to the kernel guys that, 'hey, maybe it's your bug', they were what I would charitably call unsympathetic to my plight."

Plummer used 'asserts' in the code to help diagnose the problem, meaning if the correct and proper conditions weren't met—if the 'assertions' didn't hold—while the application was running, "it throws a fault and it stops in the debugger so that you can inspect the machine to determine exactly why your assertion proved false."

He added an assert that specified CPU usage shouldn't be above 100%, which was intended to help diagnose when and where the problem was occurring in the code. However, "it was a weird case that hardly ever happened and it never fired on my machine, of course, or on any of the machines of the other people on my team."

"So I did the one thing that I felt gave me the best odds of finding out if anybody hit this case. I put my name and home phone number in the assertion. That way, no matter who in the company hit it or when or where in what building, they would be given my contact info and let me know about it."

He never got a lead though, and before long he forgot all about it.

"And then we shipped the beta. Now, I don't know exactly how many people get the Windows beta, but if it's not millions of people it's certainly thousands of folks. And now they would all be armed with code that would display my home phone number in a dialogue if things went sideways."

Apparently, though, despite still having the same home phone number to this day, no one has ever called—not until he mentioned it on YouTube a couple of years ago, anyway. I don't like to imagine how the 'oh crap' realisation that he'd potentially doxxed himself must have felt.

These are, I suppose, just some of the lengths that were gone to in order to deliver those first versions of the operating systems and software that we're so familiar with today.

Oh, and if you're wondering about the bug, apparently that got caught on a lab machine and the kernel devs confirmed it was a problem on their side and fixed it. Sometimes it's the silverbacks after all.

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