We caught up with the pioneers who brought us the Unix operating system and asked them to share some memories of the early days of Unix development.
Unix co-developer Ken Thompson worked at Bell Labs from 1966 until he retired in December 2000. He recalls this prank:
"The Unix room was on the sixth floor at one end of Bell Labs. The cafeteria was on the ground floor about a quarter of a mile away. There were dozens of ways to walk to lunch. You could pick one of four or five staircases and any segment of the six floors. One day, we were walking through the fourth floor, which was being renovated. It looked like a bombed-out city. The walls and ceilings were open with pipes and wires hanging everywhere. I noticed that there were, what looked like, speakers throughout the ceiling. I had always wanted to tap into the Bell Labs PA system and thought this was a perfect chance.
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"At night, I examined the speakers more closely and discovered that they were not really speakers, but white noise transducers. I chased the wires back to a panel that contained the generator and amplifier. Without anything specific on my mind, I borrowed the keys to the panel, duplicated them and put them back. Months later, after the construction was all done, I discovered the keys in my desk and decided to investigate. The generator was active and the amplifier volume was set to 1. In the office area, I could hear the noise, but only because I knew it was there.
"OK, I started turning the volume up by one notch every week. I would walk through the office area at least once a week on the way to the cafeteria. By the time that the volume was up to 8, still no one had noticed it but, to me, it sounded like Niagara. Everyone in the offices was screaming at each other. At that point, I couldn't help but laugh. On questioning, I told my lunch buddies what was going on. The word spread like a virus and, the very next day, the panel was open and the amplifier was removed. I still have a mental image of two people sitting across a table from each other yelling at each other in a normal conversation."
Doug McIlroy remembers Unix co-developer Dennis Ritchie, who died in 2011: