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

[Angelo Papenhoff via TUHS]

So i tried v4 on my own pdp11/40 emulator [1] and there it seems to work
fine (after i fixed a bug in the RK controller). So i guess this is a
simh bug?

aap 

[1] https://github.com/aap/pdp11

On 15/01/26, Angelo Papenhoff via TUHS wrote:
> 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
> >