====== Sixth Edition Unix ======

**Release Date:** May 1975\\
**Released By:** Bell Labs Research\\
**Source Code: ** [[https://www.tuhs.org/Archive/Distributions/Research/Dennis_v6/v6src.tar.gz|v6src.tar.gz]] in the [[https://www.tuhs.org/Archive/Distributions/Research/Dennis_v6/|Unix Archive]], browsable in the [[https://www.tuhs.org/cgi-bin/utree.pl?file=V6|Unix Tree]]\\
**Documentation: ** [[https://www.tuhs.org/Archive/Distributions/Research/Dennis_v6/v6doc.tar.gz|6th Edition man pages]]

The Sixth Edition of Unix was released by Bell Laboratories in May 1975.

It was designed to run on the PDP-11s with 18-bit addressing such as the PDP-11/40, 11/45 and 11/70. The kernel's image size was around 29 Kbytes. This edition introduced the `Portable C Library' written by Mike Lesk, which would evolve into the Standard I/O library.

For more information about Sixth Edition Unix, see [[https://www.nokia.com/bell-labs/about/dennis-m-ritchie/retro.html|The Unix Time-sharing System: A Retrospective]] by Dennis Ritchie.