V7/x86: Seventh Edition of the UNIX operating system to the x86 (i386) based PC

For those who wish to try a ‘real’ UNIX OS.

v7/x86

V7/x86 is a port of the Seventh Edition of the UNIX operating system to the x86 (i386) based PC. UNIX V7 was the last general distribution (around 1979) to come from the Research group at Bell Labs, the original home of UNIX. The port was done mostly around 1999 when “Ancient UNIX” source code licenses first became available, and was revised for release, with some enhancements, during 2006-7.

The distribution includes the full UNIX Version 7 operating system, with source code, pre-built binaries, man pages, and original Version 7 documentation. Also included are a custom UNIX-style x86 assembler, an ACK-based C compiler, and several key early UCB software components such as the C shell, the editors ex and vi, and the pager more.

V7/x86 currently supports ATA (IDE) hard drives, ATAPI CDROM drives, a 1.44M floppy drive, and standard serial ports, in addition to the usual PC screen and keyboard. For easier installation and setup, supplied utilities allow access to CD (ISO 9660) and FAT (MS-DOS) filesystems. Source code is available under a BSD-style license.

7 Likes

Seen in the discussion on HN (as linked elsewhere by @sohkamyung):

v7 Unix occupies a unique place amoung Unices, that is, it’s

the simplest possible version of Unix that is actually still functional with the code being readable

(earlier versions have much more assembler code and less C) – so anyone interested in learning Unix or one of its derivatives from the ground up is well advised to study this source code!

Although it’s noted nearby that there’s not enough C source here to bootstrap everything:

"The following limitations apply to the distribution:

  • The source to the C compiler is not part of the distribution. This is currently built separately as a component of a modified version of the Amsterdam Compiler Kit (ACK).

  • The source for boot (the second stage bootstrap) is not part of the distribution. This is currently built separately using a 16-bit version of pcc."

And of course there’s always room for an alternative view:

I would argue that Unix v6 (when you consider excellent book Lion’s Commentary on UNIX 6th edition) takes that trophy.

2 Likes

I think Minix I was the better Unix clone for the x86.
It ran on almost any PC’s . Ben.

I think I’d call Minix more of a workalike or maybe only a lookalike - but it’s certainly of great interest. I know I couldn’t quite believe that I could buy a book all about an OS and containing the source code - but I could, and I did.

4 Likes