[TUHS] merry christmas

[Steve Nickolas]

On Mon, 26 Dec 2016, Nick Downing wrote:

> I'm only an occasional contributor to the list, more of a lurker really
> since I was pretty busy this year. Well I promised a guy on the list some
> Unixy stuff that I had and have been gradually going through it and putting
> it on bitbucket but have not had time to write it all up yet.

I'm mostly a lurker myself.

> But I wanted to jump in and say something to the new people who joined the
> list owing to whatever was the recent media coverage we had. Welcome and
> all that. But IT ISN'T NECESSARY to have been around at the inception of
> Unix to get into it and to learn about the retro flavours, come up to speed
> in PDP-11 asm or learn about the old filesystems or whatever it is that
> floats your boat :)

QFT

> Personally when I discover something AWESOME I immediately want to take it
> apart and learn EVERYTHING about it. For me in the case of Unix, I quit my
> job in about 2005 and had about 3-6 months of downtime while considering my
> next moves, I had next to no money so I could not really leave the house,
> but I had a houseful of computers and a 33.6k modem so I set myself the
> task of learning about this mysterious Linux thing. I downloaded Slackware
> 4.0 onto a set of floppies and followed the Linux From Scratch instructions
> to build and bring up my own Linux flavour from that.

I got some exposure in the mid-late 90s on a Solaris shell before 
experimenting with Linux.  Actually, I installed DJGPP on one of my PCs so 
I got a basic feel for how the command line stuff worked even before I had 
Linux operational on my own systems.

> This was very educational and it highlights the main point of my post which
> is you MUST GET YOUR HANDS DIRTY, reading ancient source code is fine but
> one doesn't retain much info unless one reads for a purpose (why the hell
> won't this RK05 boot my system etc). So anyway a lot of things still
> remained a bit mysterious after my LFS adventures since they are that way
> for historical reasons, and I found myself bringing up earlier Unices on
> simh to take a peek and joining this list etc.

Knowing about the history of Unix certainly makes some of the decisions in 
Linux make more sense.

> But as I said one does not retain much unless one has a purpose and
> probably the project that taught me the most was bringing up someone's
> hobby Unix V7 clone on a cash register motherboard from the equipment I
> used to sell in my day job. The software is called UZI (Unix Z80
> implementation).

I played around with a fork of UZI on an MSX emulator once.  Interesting 
stuff, that.

<snip>

> Long story short the thing was soon utilizing various kinds of bank
> switched memory available in this cash register (which had a Z180 CPU and
> hence behaved like a Z80 with an MMU and other integrated peripherals) and
> had a network stack from Phil Karn's NOS, it had lots of communication
> ports for barcode scanners, printers, modem etc and I had them running SLIP
> and communicating with publicly available FTP servers, I used to use
> mirror.aarnet.edu.au for testing and my cash register could download small
> files.
>
> I became frustrated with the limitations of both UZI and NOS and decided to
> port 2.11BSD to the cash register as the next step, my goal was (a) make it
> cross compile from Linux to PDP-11, (b) check it can build an identical
> release tape through cross compilation, (c) port it to Z80 using my
> existing cross compiler.

A Z180 is powerful enough to run 2.11BSD? o.o;

<snip>

> Although I was not around for early Unix (was probably a 10yr old taking
> apart an Apple II and trying to learn 6502 code without the benefit of an
> assembler in 1985 when stuff like SVR4 was popular) I probably know as much
> about its internals and development environment as many people here, due to
> having got my hands dirty, albeit 30 years later.

I was messing around on the Apple //e back then myself.  Didn't know 
anything about ASM until many years later (I was *5* back then), but I 
probably could have learned it since the //c and the later version of the 
//e had built-in mini-assemblers.

> In fact I FEEL LIKE I WAS THERE. So my suggestion to newbies is, get 
> your simh on, and tackle some interesting project such as reconstructing 
> an early source for something from the fragmentary surviving pieces, 
> backporting some useful tool to an earlier Unix, or whatever. Just get 
> your hands dirty and it will be an infinitely rewarding experience. 
> Because Unix is AWESOME. Retrocomputing is AWESOME. Simulators are 
> AWESOME. :)

Heck, even v7x86 is probably enough to learn with.

-uso.