The Unix Tree

Welcome to the Unix Tree. Here you can browse the source code and manuals of various old versions of UNIX. For every file, you can also find related files from other versions: this can help show how the different versions of UNIX are related.

At present, this is a prototype and I have only made the following releases available to test the prototype. When it all works properly, I will add most of the Unix versions in the Unix Archive into the tree.

The 1970s

VersionDate
Stuff from 1972circa 1972
Two Early C compilersJuly & Dec 1972
Third Edition UNIXFebruary 1973
The `nsys' kernelAugust 1973
Fourth Edition UNIXNovember 1973
Fifth Edition UNIXJune 1974
Sixth Edition UNIXMay 1975
Mini UNIXMay 1977
Seventh Edition UNIXJanuary 1979
The Interdata Port of 6th EditionJune 1979
The 32V KernelJune 1979
AUSAM from UNSWNovember 1979

The 1990s

VersionDate
Net/2 /sys/kern, /sys/ufsJune 1991
2.11BSD UFS implementation1992 to 2001
4.4BSD-Lite UFS implementation1995
FreeBSD-4.3 UFS implementation1996 to 2001

Comments on Related Files Algorithm

The algorithm I am using to determine how closely related files are is very primitive. I just count the number of common lines in the files, after truncating whitespace and converting to lowercase. I don't consider the order of the lines or anything. However, this seems to give reasonable results anyway.
Warren Toomey, wkt@tuhs.org, February 2002