A Technical History of Apple's Operating Systems

An anonymous reader writes "As part of his 1680-page book Mac OS X Internals: A Systems Approach, Amit Singh of kernelthread.com wrote a very detailed technical history of Apple's operating systems. Since he had to cut down on the history chapter because of the book's already too-large size, most of this chapter didn't make it to the printed book. Singh has made available the history chapter as a free PDF. The file is 140 pages long, and is generously filled with figures and screenshots. It starts with the internals of the original Apple I and goes through a tour of all operating systems Apple dabbled with, including internals of A/UX, Lisa OS, and such. It even covers details of outside influences like the Xerox Alto, STAR System, Smalltalk, and Sketchpad, and closer to home things like Mach, NeXTStep, and OpenStep."

Apple ][

[BWJones]

One of the coolest things about the Apple I and Apple ][ was that Apple Computer included the schematics for *all* of the motherboard and CPU design. Everything was documented so that users could build interfaces with both the software and the hardware with a minimum of fuss. So, even though Amit Singh calls the manual included with the Apple ][ as a "preliminary manual, it was remarkably complete.

Despite how far we've come, there are time I really miss my old Apple ][.

I did

[LKM]

Daring Fireball wrote about this recently [daringfireball.net]. Here's the most important quote of the article:

The difference between the old Mac OS and Mac OS X isn't that it used to suck but now it's great. The difference is that Mac OS X's appeal is broader; it is good in more ways than the old Mac OS was.

Yeah, I did use and like Mac OS 9, Mac OS 8 and System 7. I did smoke lots of weed, but that had nothing to do with it. There are two things to consider: First, it went up against crap like Windows 3.11 and Windows 95. Second, it was the prettiest, most easy-to-use OS, even with cooperative multitasking and lack of memory protection.

Mac OS X added a lot to what makes a Mac great, but Mac OS 9 had a lot going for it, too.

Learn concepts, not imlementations

[LKM]

I took OS comparison course in MIT's business school some years back, and must say of all the courses I took in computer science, that one became the least useful the quickest.

That's why you should always learn concepts instead of implementations. Concepts remain useful and can be used to judge new implementations, while implementations always go away eventually.

Re:Apple ][

[booch]

I think that's what they wanted you to do. Even if you didn't buy a Sony TV, a substantial percentage of people will, so Sony wins by making you buy a new TV instead of fixing your old one. Or they win by charging you an outrageous price for the schematics and repair manuals.

And the reason that they do this is that they (and you) don't have to pay the real cost of disposing of the old TV. Instead of recycling the TV and reclaiming all the materials, you'll probably just toss the old TV in the trash. And the hazardous chemicals will leak into the soil. Our descendents will have to clean that shit up eventually, which will cost tons of money. But we don't have to pay that, so we just go get a new TV cheap.</rant>

Re:I did

[Haeleth]

For all practical purposes this was the state of things for many years.

It's a rather misleading description, though. More accurately:

• UNIX/Windows NT/OS X - if a program needs more memory, the system gives it more memory; if there is no more memory to give, the program is terminated.
• Windows 9x - if a program needs more memory, the system gives it more memory; if there is no more memory to give, your computer crashes.
• MacOS 8/9 - if a program needs more memory, the system tells you and you have to fiddle around with a fussy little dialog box to give it more manually and try again, at which point another program will complain that it no longer has enough memory. Repeat ad infinitum, all the while gritting your teeth and reciting the mantra "this is better than Windows, this is better than Windows" until you almost believe it.

Re:Archeological dig

[boarder8925]

I'll go with you, just so long as we make a video of it like these guys did when they dug up E.T. the Extra-Terrestrial [keithschofield.com] for the 2600 [wikipedia.org]. ;)

Re:Apple ][

[Gospodin]

Our descendents will have to clean that shit up eventually, which will cost tons of money.

Or they'll have developed pollution-eating bacteria and it'll cost about a nickel. We really don't know, do we?

Re:I did

[TheRaven64]

if there is no more memory to give, the program is terminated.

On most UNIX systems, if there is no more memory to give then malloc() fails (returns NULL) and you can then try freeing memory elsewhere and trying again, or go into some recovery mode (typically make sure everything is saved and then quit).

On Linux, if there is no more memory to give, then a random process is terminated.

Re:I did

[LKM]

So your personal mantra would be "crashing is better than telling me if there's a memory problem"?

Re:No wonder the book is 1680 pages

[DurendalMac]

Believe it or not, there ARE people out there who are interested in this kind of detailed history. Simply because you're not interested doesn't mean that others don't want to read it.

Re:I did

[gEvil (beta)]

If a program crashed because it was out of memory, and you consequently raised its memory limit and then tried to reopen it, and had insufficent memory, that was your cue to either buy more RAM, or quit some other programs. (Or increase the virtual memory limit, at the expense of speed.)

Or reboot, because even though you might have had enough available free memory to run an application, it might not have been enough contiguous free memory.

Re:Apple ][

[mrchaotica]

That doesn't change the fact that assuming that the future will magically fix all the problems is entirely irresponsible.

Re:Being too greedy?

[MacDaffy]

A bunch of us engineers spent the time between Copland's abrupt halt and the NeXt acquisition trying to figure out which operating system the company was going to try. There was a lot of experimentation with MkLinux and some talk about beefing up A/UX but the biggest buzz was coming from the BeOS. A few of us made the pilgrimage to Menlo Park, saw their presentation, and were mightily impressed with its performance, but we agreed that the lack of available consumer applications made it a non-starter.

From the time Copland died in the summer of 1996 until we got laid off in March of 1997, we waited for the Big Decision and learned a lot about UNIX-based operating systems because we knew that's where the company had to go. NeXt and Steve Jobs's return were complete surprises. Smartest move Gil Amelio made--just as was Steve's immediately getting Gil out of the way and resuming leadership. Apple's customers needed a reason to believe and Gil only provided silence. As one Rumor-Monger wag said, "he couldn't market pussy in a prison."