Plan 9
More info
- Creators
- Rob Pike, Ken Thompson and others, Bell Labs
- Released
- Type
- Operating system
- License
- MIT (since 2021)
Bell Labs' successor to Unix, built by the same people, taking "everything is a file" all the way — and used by almost nobody.
In Unix much is a file, but not everything: networking, windows and processes are reached through system calls with their own interfaces. Plan 9 made every resource a file system speaking the 9P protocol, which means a remote machine's graphics card or network card can be mounted locally with no special code. Every process also gets its own namespace — the same idea containers were built on twenty years later.
The system never became a widespread product, but its parts travelled. UTF-8 was sketched by Ken Thompson and Rob Pike for Plan 9 on a diner placemat in 1992 and is now the web's character encoding. Namespaces exist in Linux, and the Go language carries clear traces of the same thinking.