On Sat, Jul 4, 2009 at 10:44 AM, Peter Frederick <psf...@earthlink.net>wrote:
> It's actually amusing that we are now all running the OLDEST OS around -- > Unix was developed in the mid 60's by a pair of computer researchers (note > that they were NOT hackers -- both had PhD's, I think, in computer science > or something) on a PDP-11 8 bit processor with a couple thousand bytes of > ram and tape drives. > Bell Labs (AT&T) UNIX (originally called The UNICS Project as a play on MULTICS) was developed by Ken Thompson and Dennis Ritchie who actually were hackers. Some of the very first actually. A hacker, as defined by the RFC 1392, is "a person who delights in having an intimate understanding of the internal workings of a system, computers and computer networks in particular." > The result, of course, since they weren't doing "slap something together > and sell it today" but actually designing a system for multiple tasks on a > single machine, things like priority and task switching actually work, and > potential conflicts are resolved a priori rather than some software klugde > after a new program of some sort locks up the processor. > > The original intention was to produce a multi tasking multi-user system, > but that wasn't possible on the available hardware, required too much memory > and processor cycles. However, the end result was a stable system sold for > decades by AT&T for very high prices. Fully assembler written originally, > but very soon written in "C", so it was portable between architectures so > long as a "C" compiler was available, which they were. Actually ... at the time, they were not. Thompson created the B programming language with the Assembly code of UNIX to have a language to build apps for the new OS. Ritchie extended B and created C as a means to take advantage of features in the PDP-11 that were not available in the PDP-7, and which B could not utilize. It was a couple of years before C was powerful enough to recode the entirety of UNIX, at which time it was still operating solely on PDP-11's. However C quickly became powerful enough to allow cross compiling and granted the ability to move UNIX as a whole with minor machine specific changes to other platforms. Eventually AT&T got out of the computer research development business and > Unix kernel (not application or interface) development continued at BSD, > which I believe is part of the University of Berkeley in some form. Technically, the BSD Release 1 was available while Bell Labs was still in computer research. BSD itself stands for Berkeley Software Distribution and is the operating system developed by the Computer System Research Group at the University of California, Berkeley when AT&T gave away the keys to the kingdom. In the early days, the mainframe took up an entire floor of a building and cost quite a lot of money. The software was secondary since you had to have the computer to run it, and as such, the source code was included as a matter of course. Bill Joy, a graduate student in the late 70's, made his own changes and additions to the Bell UNIX system and thus 1BSD was born. AT&T didn't exit the UNIX market until the very late 80's, maybe early 90's > That means it's open source, although just the kernel, nothing else. The > Mach 10 BSD kernel is the core of Mac OS 10, Windows 2000, ME, XP, Vista, > and 7, and will probably be forever unless someone spends the time writing > something else, which is rather unlikely. This is incorrect. Windows ME, was Windows 98 Third Edition, and as such was still using full blown DOS at the kernel. Windows NT, on which Windows 2000, XP, Vista, 7 and all Server versions are built, is *not* UNIX in any shape or form. Windows does not provide true multi-user multi-tasking in the way that *NIX does. NT provides POSIX compliance, meaning that POSIX compliant UNIX code can compile and install on an NT system, but the kernel itself is closer to VMS than UNIX as the lead system engineer from DEC was hired by MS to build NT. However it also is not VMS in a pure sense either. NT is NT. Mac OS X uses the Mach microkernel, which was developed at Carnegie Mellon, and is not in fact BSD at all. Mach was actually originally intended as the replacement for the BSD kernel. Which is why Mach is BSD-like, but is not code compliant with BSD as BSD is a macrokernel. > I believe that Linux in all its implementations switched to the Mach 10 > kernel some years back instead of the one that Linus Torvald wrote as a > class exercise to generate a multi-tasking kernel (based on the "clone" of > Unix his professor wrote as a teaching tool called Minix). All the functions > of Unix were there. > This, also, is incorrect. Linux still uses the original style macrokernel, and has nothing at all to do with Mach. Mach, except for Mac OS X, is no longer in active development and is near dead as a platform. BSD chose to continue their own development track and Carnegie Mellon has stopped allocating funds. Apple Mach is no longer pure Mach in that sense either, as Mellon Mach and Apple Mach are incompatible in several areas. Linux *is* the Kernel. Linux = NT = Mach = BSD - Not Linux = Mac OS X = Windows = OpenBSD Unix, however, as you will know if you've ever used it as a command line > implementation, is a main frame OS of the old style -- cryptic commands, a > hangover from when using whole words would eat up your disk or memory space, > seriously complex operations available (the reference texts for the common > command "shells" take up several yards of shelf space if printed), and hard > to use. A typical PC user won't every make much progress with it for that > reason, since the vast majority use them for word processing, email, > internet browsing, and games, not bank transfer recording or signal > processing, etc. > > So the idea of a graphical interface popped up (at the Palo Alto research > facility run by Xerox) in the late 70's. No, Apple didn't invent it, nor > did Microsoft -- not the idea, the icons, the desktop, nor the mouse. Xerox > ate itself shortly after (these were the days of the Diablo Hy-Type II, if > you remember them -- metal daisywheel printers) for reasons unrelated to > computers, and the idea of a graphical interface was taken up by Apple and > Microsoft. The "windowing" system is the result. > Xerox, actually, did not invent GUI either, perse. The very first computer mouse was developed in the early 60's at Stanford Research Institute and was used to manipulate a screen full of text based links. Xerox merely extended this idea by replacing the text links with picture links. Yes, Apple fully stole the GUI concept for the Lisa (not the Macintosh) as Xerox did not require any type of NDA when they invited Jobs and several engineers in to view their early system. Apple implemented one on the Mac in 1984, Microsoft started about the same > time, but ran later (as Microsoft always does) and the X-Window system was > developed for Unix. > Macintosh 84, Windows 95. Jobs made the same mistake Xerox made and invited Gates in to view the first Lisa prototype. Currently, Apple uses Aqua, Microsoft has produces Windows 2000, ME, XP, > Vista, and now 7, and Linux uses various implementations of X11 (open > source). They are all different, and Microsoft's are bogware by and large > in my opinion, and the Linux versions vary much more (KDE and Gnome are the > most common, but Sun and Corel have their own, and there are more). > Apple uses Mach with Aqua, Microsoft uses NT with Windows and *NIX uses, well, whatever they want. Very flexible *NIX is. KDE and Gnome are *Window Managers* ala Explorer in Windows. As such they are not complete Window systems. You can not run KDE without X11, however you can have a GUI on a *NIX system without X11. View QNX that uses not only a Real Time microkernel called Neutrino but also their own GUI called Photon which has nothing to do with X11, KDE, Aqua or Windows. In my humble opinion, QNX is simply beautiful. Far more elegant than Mac OS, and far faster than Windows as an OS. But it's very niche, and as such, requires high levels of activity for porting of applications. Great embedded though, lots of early automotive computers were running Neutrino. > The current "versions" of Linux are mostly the same actual code packaged > with installers and commonly used software so that the typical Mac or PC > user can install them without having to learn to use the Bourne shell or > something. I fall into that catagory -- if I were retired it might be fun > to learn to install Unix by hand when I was snowed in or something, but I > prefer to stick in a disk and end up with a working system in an hour or two > instead. > > Linux also exists as bootable CD and DVD versions, which are VERY handy for > things like troubleshooting non-booting XP installs and file transfers from > busted XP or other windows boxes rather than installing the OS again. > > Peter EdB -- "I'm a Night Elf Mohawk!" - Mr. T. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://okiebenz.com/pipermail/mercedes_okiebenz.com/attachments/20090704/bc3cc256/attachment.html> _______________________________________ http://www.okiebenz.com For new and used parts go to www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
