It's the late 1960s, and this U.S. Marine Corps pilot fish is charged with keeping track of more than 100,000 Marines in the Western Pacific and Hawaii -- using, fish says, "an IBM 1401 mainframe and lots of cards."

Which means fish spends much of his time traveling between Vietnam, Hawaii and Washington, updating the ranks and specialties of the Marines and how long it's been since they were rotated into or out of Vietnam.

As Christmas approaches, fish is in D.C. with his headquarters counterpart, frantically working on a semiannual staffing report.

"Because only one airline was serving Hawaii, I booked my return flight for Dec. 24 so I could be with my family for Christmas," fish says. "Next available flight was the middle of January."

But after a 24-hour shift pumping cards into the 1401, the machine prints out final tallies -- and out of 100,000 Marines, 55 are missing.

"What do you think happened?" asks fish's counterpart.

"Almost certainly the Radio Battalion," fish replies.

Fish knows the Radio Battalion does intelligence work, and its members are dispersed among other units -- "so super-secret that they're not acknowledged to exist," fish says. "The report totals were coming up wrong because of secret allocations to other units to disguise the existence of the Radio Battalion."

Fish reports to the general in charge, and explains the likely source of the discrepancy.

The general's response: "Fix it before you try to leave!"

Fish returns to the computer room, where his co-worker waits. "Give me a card," he says.

And a few minutes later, the totals add up.

"One card, one adjustment," fish says. "The totals were technically wrong, but the general officer understanding was perfect.

"Problem fixed, general happy -- and I had a great Christmas with my wife and kids."

Now help fix Sharky's problem: Never enough true tales of IT life. Send me your story, new or old, at sharky@computerworld.com. I'll be back to ring in the New Year, but in the meantime you can comment on today's classic tale at Sharky's Google+ community, and read thousands of great old tales like this one from the Sharkives.

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