Unix Was Built to Play a Game
Zusammenfassung
Ken Thompson created Unix in 1969 partly because he wanted to play a video game. His game “Space Travel” — a simulation of the solar system — had been running expensively on a GE 645 mainframe at Bell Labs. When Thompson found a disused PDP-7 with a nice vector display, he ported the game to it. To run the game properly, he needed an operating system. He wrote one. The operating system became Unix.
The $50 Game
Ken Thompson had written Space Travel for the GECOS operating system on a GE 645 mainframe. The game simulated travel through the solar system — players could pilot a spacecraft and land on planets. It worked, but each run cost roughly $50 in computer time, and GECOS’s batch-processing model meant long pauses between moves.
Thompson found a neglected PDP-7 minicomputer in a corner of Bell Labs. It had a sharp vector display, it was available whenever he wanted it, and it was essentially free to use. He ported Space Travel to the PDP-7 — but the machine had no operating system suitable for the game. So Thompson began writing one.
The Operating System Written in Three Weeks
Dennis Ritchie later described Thompson’s approach: he needed a file system, a process model, and a small set of utilities. Working quickly, Thompson implemented these over roughly three weeks. The system he produced was an early prototype of Unix.
Ritchie joined the project. Together they formalized the design, rewrote the kernel in C (a language Ritchie was simultaneously developing), and produced the operating system that would eventually run everything from servers to smartphones. The PDP-7 itself was a dead-end machine — Bell Labs moved to a PDP-11 shortly after — but the OS it spawned was not.
The Connection Thompson Made Himself
The causal chain is direct, and Thompson and Ritchie both described it plainly: there was a game, it needed hardware, the hardware needed software, and the software grew into an operating system. The game itself is historically minor; the operating system written to host it is not.
Space Travel was never commercially released. The source code survives and has been ported to modern systems. Unix, meanwhile, is the ancestor of Linux, macOS, iOS, Android, and every major operating system except Windows.