World Library  
Flag as Inappropriate
Email this Article

Rio (windowing system)


Rio (windowing system)

rio is Plan 9 from Bell Labs's windowing system. It is well known for making its window management transparent to the application. This allows running rio inside of another window manager.


  • Design concepts 1
  • History 2
  • See also 3
  • External links 4

Design concepts

Many of its features embody key Plan 9 design concepts:

  • Each window runs in its own private namespace.
  • It exports a file system interface to running applications. This interface is the same rio receives from the operating system, so rio can run inside a rio window without any special arrangements. Because the interface uses 9P, rio is network transparent even if it doesn't include any network-aware code.
  • Windows are treated as completely editable text.


rio is the latest in a long series of graphical user interfaces developed at Bell Labs, mostly developed by Rob Pike, including the first graphical window system for UNIX (which predated X), the concurrent window system, and the Blit.

rio was a complete rewrite of in Alef. Its main change was that it stopped parsing and rewriting graphical commands and let the client write pixels directly. This was done mainly for efficiency. As Alef disappeared due to being too difficult to maintain given the number of people working on Plan 9 at the time, rio was rewritten in C. This was done using the Plan 9 thread library which was inspired by Alef and had most of its features, like blocking channels for interthread and interprocess communication. Another important change, due more to the environment than to rio per se, was that rio supported full colour, using alpha compositing, whereas 8½ used bitblt operations.

See also

External links

  • Rio: Design of a Concurrent Window System by Rob Pike
  • rio(1) manpage - Rio manual.
  • rio man page(4)
  • The 8½ paper - Describes rio's predecessor which had a very similar design

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.