Plan 9 (operating system)

Plan 9 is an operating system descended from Unix and developed by Bell Laboratories. It is not a Unix variant, but is very similar. Plan 9 explored several "simplifications" to the original Unix model that improved the experience of using and programming the system, notably in distributed multi-user environments. Plan 9 was a Bell Labs internal project for a number of years, but a public release was made in 1993, followed by a shrink-wrapped version in 1995. Bell lost commercial interest in the project in the later 1990s, and released a third version under a non-free license (but with source code available) in 2000, and finally under a new open source license in 2002. This is the 4th, and current, edition of the system.

See also

Standard Plan 9 utilities

• rc - the Plan 9 shell
• sam - a text editor
• acme - a user interface for programmers
• plumber - interprocess messaging
• Mk - A tool for building software, analogous to the traditional Unix make utility.
• namespace
• rio - the new Plan 9 windowing system
• 8½ - the old Plan 9 windowing system

Implementation artifacts

• 9P - a filesystem protocol
• rendezvous - a basic synchronization mechanism
• Brazil - what became the Fourth Edition of Plan 9.

Influenced

• Plan 9 from User Space - a port of many Plan 9 libraries and applications to Unix-like operating systems.
• Inferno - distributed operating system following up Plan 9
• Plan B - research operating system based in Plan 9
• 9wm - X Window manager that clones the Plan 9 interface
• wmii - X Window manager that uses a file system-like interface based on 9P