[TUHS] UNIX v4 Source Code Commentary - complete book now available

[Angelo Papenhoff via TUHS]

Looks very nice, thanks!

I was wondering about the RK driver, because there are issues with it.
The v4 RK11 driver does not work with simh emulation correctly when
using multiple disks. I've had to use the v5 driver for my v4
installation guide to get a usable system. Looking at the code i had the
impression that the v4 driver is fine (it also matches the nsys RK
driver, which i've also had trouble with recently. haven't tried v5 RK
with nsys yet). What i suspect is happening is that the seek/read dance
isn't working correctly, either in simh, or there were faulty
assumptions that only work on real hardware more or less accidentially
(the rewrite in v5 might suggest the latter).
In any case it looks like blocks aren't being read correctly, and
whatever process is waiting for the read will hang.

Would be nice to get to the bottom of this.

cheers,
aap

On 12/01/26, Briam Rodriguez via TUHS wrote:
> Hello,
> 
> Following the incredible recovery of the UNIX v4 tape from the University
> of Utah last month, I've written a comprehensive line-by-line commentary
> on the entire UNIX Fourth Edition source code.
> 
> The book covers:
> - The kernel (boot, processes, memory management, scheduling)
> - The file system (inodes, buffer cache, namei)
> - Device drivers (TTY, RK05 disk, character devices)
> - User space (shell, utilities, C compiler, assembler)
> - Plus appendices with system call reference, file formats, and PDP-11 guide
> 
> It's open source (CC BY-NC-SA 4.0) and available on GitHub:
> 
> https://github.com/unix-v4-commentary/unix-v4-source-commentary
> 
> The PDF is included in the repo for those who just want to read.
> 
> It is my sincerest hope that this book can help someone, and I'd 
> appreciate any feedback (and changes!).
> 
> Many thanks to Robert Ricci, and Al Kossow, and everyone involved in 
> recovering this historic code.
> 
> Without that work, this book wouldn't have been possible. Also thanks to 
> Mr. Warren for letting me in to the mailing list!
> 
> Please don't beat me up too bad!
> 
> Humbly yours,
> 
> Briam Rodriguez
>