Hmm ... do I want to get in the middle of a fight with my friends and get them all mad at me… but I guess I cann’t just keep quiet on this debate.

 

Basically I think Larry and Dan are having the Dan Akroyd/Gilda Radner  “Shimmer” Dessert Topping / Floor Wax debate.   That said, I do think systemd is a giant step backward for most of the same reasons others have already said, so I’ll not pile on and stick to the basic what does it mean to be Unix or not/what is an improvement or not, discussion.

 

Larry observes:  “I maybe think the reason you think that things aren't relevant anymore are because young people don't get Unix, they just pile on to this framework and that framework, NONE OF WHICH THEY UNDERSTAND, they just push more stuff onto the stack.”

 

Simply, I could not have said that better.  But that is a symptom of the problem.  Frankly, with frameworks and the like, we have added so many levels of abstraction, we have completely lost sight of the real issues and many folks really don’t “think like a programmer” any more.   Remember, UNIX was a system by programmers for programmers.  Much work since has been hiding a lot of what made it great IMO - which I think has caused the most damage.

 

What makes a system a flavor UNIX or not is almost personal, based on what you value (or not).  But the fact is no matter what you call it, “UNIX” is the core kernel with a small and simple set of operations, plus a set of programs that are all based on the simple ideas, basic concepts and mostly solid mathematics/computer science that a small group of people in NJ came up with at the time, when they suggested there might be a better way to put things together than had been otherwise popular at the time.   Their concepts and ideas collectively were different enough that they were encouraged to write a paper about it.  That paper was accepted and published in CACM, it got a lot of people in the community interested in those ideas and  the rest is history as we say.

 

But a huge difference between then and now is the economics and thus the matching equipment they used to explore those new ideas.  So some solutions, we take for granted today, would not be practical, much less even possible in those times.

 

Just like some people trying to claim that ‘Linux’ is not UNIX, falls away deftly as well as it did years ago when other ‘progressive’ features were added to 'Research UNIX' and we got systems like BSD 4.1 much less 4.2.  Remember smart people from Rob’s “cat -v” paper to Henry Spencer (“BSD is just like UNIX, only different” net.noise comment) in those days railed on the new BSD system as not being ‘UNIX’ either.  For good or for bad, many of the things we take for granted today as being required in a UNIX system, go back to UCB features (or features from AUUG, MIT, CMU or similar).

 

I’ve also stated many times, I do so miss the simplicity and cleanliness of V6 and V7, but I would not want to use it for my daily work today.  So many of those very features that Henry and Rob pointed out back in the day, have somehow proven in fact to be ‘helpful’ or at least comfortable.  While a few of us probably could live with something like ed(1), particularly with a front-end/feature more like Plan9’s sam(1), than absolutely having to have VI/EMACS.

 

Let me offer an example as a thought exercise.     I was recently helping a young hacker trying to get V5/V6/V7 going on a PDP-11 simulator so he could play with it to learn more about the 11 and UNIX itself.  I gave him some help and without thinking about it in my email I mentioned that he try something, but I had forgotten that the program head(1) was a Bill Joy program wrote in 1977.  What UNIX box would not have it today?  As it is screwed into the ROM in my fingers when I type (actually the sources to head(1)  is less than 200 lines with ¼ that being the BSD copyright, I sent him them and suggested he recompile it - partly as an exercise to see how C changed).

 

But note that when wnj wrote head(1), Joy followed the famous ‘Unix Philosophy’ of  doing one (small) job well.   Which means he did not add a feature i.e. abusing, an old program, like cat(1), and add some new switch to it that that told the program stop outputting after n lines. Instead Joy wrote a simple new tool.

 

This is the problem with what Larry was pointing out, I think frameworks and like are just adding features on features on features to current subsystems.   Yeech!!!

 

To me what made Unix ‘great’ was that this small (16-bit) system, with 48k-256K of memory can could practically owned by a department at $150-250K would allow you to do the same sorts of things that took a $1-4M type of system (be it a PDP-10 or IBM or the like).

 

Mashey did his ACM lectures called “Small Is Beautiful”, sometime after they completed PWB 1.0 and this was one of his points.   Unix was a small SW system on a small HW system platform, but was clean and did what you (the programmer) needed without a lot of extra cruft.  IIRC for PWB 1.0, that was an 11/45 as the recommended system to run it.  Not the smallest (11/40), but hardly the 11/70 either.   But as the 32-bit systems became available, many of the different constraints of the PDP-11 were removed – first data size and then text size.  When the VAX came and 32-bits was infinite (probably still is for text space), performance got better (and cheaper), disks got bigger, etc.

 

And because it was less and less of a problem, quickly programmers got a tad lazy or at least stopped paying attention to things they were required to consider in the past.  Ex (or for that matter EMACS) in thinking was the first the UCB “explosions”  and maybe where UNIX began to be a tad different and look less and less like what had come from the NJ avengers.  The resources of the new systems were such that you did not need a new set of small programs, you added features (extensions) to the old – and that was (is) a trap which we seem to follow today.

 

I think other folks like to point out all the new wonder new functionality in the Linux kernel (or FreeBSd or macOS etc...) have brought to the UNIX world besides BSD’s sockets networking (loadable drivers, dynamic devices are super and I would not want to be without either).  I like shared libraries, and better memory systems.  Although of course on my supercomputer what are two things we turn off (shared libraries and much of the fancy memory stuff - cause they get in the way of real programs ;-). 

BTW:  I also think sockets were (are) a terrible addition to UNIX and we did not really need them. We are stuck with them now, but  I would rather have had something more like what ChaosNet and the original UofI Arpanet code, or what UNET did, where much of the network stack was in user space [which in fact was what the Interface BBN originally used].  In other places, over time, we have added window managers GUI’s et al.  Hey the core C compiler’s code generator is remarkable compared to what it was for the PDP-11, plus we have new languages be they Rust, Go or even C++ and Java.

 

The key point is few people are really asking the question, if I add this new feature what does it cost, and what do we really get for it?

 

The truth is many of these features are all comforts and I do like many of them and I use them and want many of them.   I like kernel support for MxN threading, but that took kernel support – what did we get beyond fork/exec that we really did not have (the answer is probably better performance due to tighter control, but I wonder if we bought much more than that).  I’m typing on a Mac, while most of why ‘work’ these days is targeted Linux.  But what is common is mostly I can work in the manner I want.  I have something that does make some things nice (easier)… Both are ‘UNIX’ in some manner – that core of both are the same core ideas I see in V5/V6/V7 – that’s good.  i.e. they both work as a floor wax….

 

But all of those new features have come at a cost, the biggest is complexity/bloat.  We have lost a lot in the design because today’s programmers just don’t have to deal with the kind of constraints that some of had to deal with years ago and I think you hear a number of us groaning that when papers like this one come out, they have completely missed the point and really don’t understand what it means to be UNIX.

 

I suspect if VM/TSO or VMS had become the core technology of the future, the papers being written today would be just as damning.  If you never lived in the old world, I’m not sure you understand the improvement.

 

I’m going to toss the gauntlet with a slightly even more political statement.  When I read that paper, it reminded me of the current round of anti-vaxxers.   Those of us that remember polio and other ‘childhood diseases’ have no desire to go back in time and relive it.  I really don't want to run VMS/RSX or for that matter TSS/360 which was the first system I really ever knew how to use well.

 

So in the same way, UNIX is the core technology we have today and I’m damned glad it ‘won’ be it called Linux, FreeBSD or macOS.  It was not perfect then and it is hardly perfect today.  But it was different from what we had at that time, and so much better - that today we now use those ideas from UNIX as our core ideas when we build systems.   I just wish people would understand what they have and see it for the positive instead of trying to knock it down - ‘standing on the shoulders of the giants’ and showing what they did as a help, but based on solid ideas, instead of stepping on the toes trying to make their new thing/feature more valuable and claim it’s not made from the origin story.

 

Hey Chevy… can I have some “shimmer” for my pudding.