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Quality control, Soviet style: Here's another fine message you've gotten me into

Hacker News - Mon Apr 12 11:40

Who, Me? We return to the Cold War in today's Who, Me? Start your week with suspected sabotage, computer sleuthery, and a satisfying slug of Grand Marnier deep in the heart of 1970s Москва.

It was 1978 and our reader was working for a firm that had just sold a computer to the company that manufactured the Moskvitch.

Sadly now defunct, the Moskvitch was the must-have car of the time for citizens of the Soviet Union (officially, at least). Despite being the butt of a thousand jokes, demand for the vehicle outstripped supply and people found themselves with a substantial wait before they could get their hands on the rear-wheel-drive engineering marvel.

Our reader, who was initially Regomised as "Boris", but whom we've opted to call "Ivan Ivanovich" was sent to the site to investigate multiple mysterious system crashes.

A bit of background: a bespoke application known as "the 'Quality Control' system" ran on this computer. "It was actually a messaging system," Ivan explained, "whereby inspectors at the end of the line could send messages to assembly stations, such as 'rear door installed upside down.' I know it seems laughable now, but at that time, this was big business."

However, there were problems. The system crashed at least once per shift, causing delays in production. "An enterprising salesman took advantage of the problem to sell them more memory, and the fault reduced to once a day (they worked two shifts a day)," said Ivan.

A bit better, but still not right. The company's top communications experts looked into the problem, but came up empty. And so it was that Ivan who, by his own admission, "knew nothing about comms" was sent to Moscow on a year's contract as Project Manager and given a simple brief: "Just stop the bloody dumps!"

At the plant, Ivan shared an office with 13 other programmers and a VDU, which had been negotiated as part of the contract. His job title also scored him his own car and a diplomatic apartment. Not really knowing where to start, he fired up the newfangled screen and watched the internals of the computer doing its stuff.

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"I had imagined a dynamic environment," he said, "with messages flying hither and yon as the treasured vehicles issued forth from the track..."

He did not see that. What he actually saw was a queue of messages sent to one assembly station. A queue that got bigger and bigger until the memory filled up and the computer crashed.

"A little delving," he told us, "showed that the fancy Italian teletype terminals (3-case: upper, lower, Cyrillic) were put into 'send' mode when any key was pressed, and could only return to 'receive' mode when 'send' was pressed.

"Someone on the track had learned how to silence the poxy terminal – just press a key!"

The bespoke software had no way of knowing what had befallen the terminal and so just kept on sending messages until the computer fell over.

The fix was trivial. Ivan told us it was a mere 13-line patch that added a 255-second timeout on the input. What was not trivial was how to test his work.

"After much negotiation, a meeting was scheduled at the control centre of the production line for midnight-thirty, after the second shift had closed.

"The production manager, the computing manager, the translator, the chief programmer, the protocol (KGB) lady and I – we all assembled in the silent factory.

"I loaded the fixed comms software, started a program which sent regular messages to an adjacent teletype, looked at my watch... and pressed a key. We waited. My watch showed 250 seconds, 255... 256... 257... OMG! And then the tty burst forth, pouring out messages until there were no more.

"The system clock was a little slow."

He headed back to his apartment through the dark and silent city, a large and suitably adult beverage on his mind.

As for the remainder of this contract – all 45 weeks of it – Ivan didn't have much to do so amused himself by writing an interactive debugger. Doubtless handy for tracking down issues not related to someone on the production line getting creative with the keyboard. Although the sabotage that had caused the problem in the first place was never mentioned again.

On his last day he brought in six bottles of spirits and he and the programmers made many toasts to the quality of the Moskvitch. It was, he admitted, "a very enjoyable day's work" and, lubricated by Cointreau and Grand Marnier, the team spoke more than they had for the whole of the preceding year: "They were human after all!"

"I never drove a Moskvitch, though – I had a Lada."

Ever applied a patch under the suspicious eyes of the intelligence services? Or bought a car with a door fitted upside down? Let us know, with an email to Who, Me?. ®