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86 votes
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Were any of the books mentioned in this scene from the movie Hackers real?

As indicated on IMDb, the books are Green: International UNIX Environments, probably part of POSIX or The X/Open Guide. Orange: Trusted Computer System Evaluation Criteria, part of the Rainbow ...
Stephen Kitt's user avatar
45 votes
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Why does this BASIC program declare variables for the numbers 0 to 4?

These tricks are usually done to increase speed or reduce space. For most (especially Microsoft) BASIC, constants are stored within a tokenized line as ASCII (as entered), and converted to a floating ...
Raffzahn's user avatar
  • 218k
44 votes

Filesystems with versioning

FILES-11 on DEC minicomputers was a versioned file system -- RSX-11M, IAS (on PDP-11), VMS (on VAX, Alpha). Version numbers are very user-visible; they are part of the syntax for specifying a file. ...
dave's user avatar
  • 35.2k
37 votes

How does the ‘real mode flat model’ work?

I’m assuming you’re asking about x86 processors, not the older 8-bit CPUs. Real mode is always segmented, and everything (CPU, operating system, programs, even peripherals on the CPU bus) has access ...
Stephen Kitt's user avatar
37 votes

How is it possible that they used to type "Mb" when they meant "MB" in printed computer magazines in the 1990s?

Was not the "B = byte, b = bit" standard established even back in the day, in the 1970s/early 1980s? Not really. It existed (I think at least as far back as 1979's JEP100, but I don't have good ...
hobbs's user avatar
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32 votes
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Where can I find the debate around snow-free screen updates mentioned in the Zen of Assembly Language?

The discussion started with an article by Augie Hansen, Instant Screens, in the June 1986 issue of PC Tech Journal. That article describes the snow problem in detail, and presents a technique to avoid ...
Stephen Kitt's user avatar
29 votes

Unix Haters Handbook - guaranteeing synchronous, atomic operations

If you can ensure a reliable connection, synchronous, atomic operations can indeed be implemented using various techniques that also work for remote connections, much in the same way as they can be ...
DarkDust's user avatar
  • 1,490
29 votes
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Which computers did Donald Knuth "mix" together to get MIX?

Section 1.3.1 of The Art of Computer Programming says the following: MIX is the world's first polyunsaturated computer. Like most machines, it has an identifying number—the 1009. This number was ...
28 votes
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Were printed manuals for HP PCL or GL ever published?

My bookshelf says yes, they definitely were: They don't appear to have ISBNs but there are HP part numbers: PCL 5 Printer Language Technical Reference Manual is 5961-0509 (1999 edition? Part 1, Part ...
TomH's user avatar
  • 396
25 votes

Filesystems with versioning

There were quite a few operating systems that had file versioning in the same era as unix. Many file systems that we are familiar with today just have some components of a file name, such as: Name....
Brian Tompsett - 汤莱恩's user avatar
25 votes
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When did "Zen" in computer programming become a thing?

As Ross Ridge already mentioned, it's a stream of titles started with Robert Pirsig's book Zen and the Art of Motorcycle Maintenance of 1974. This book was a rather unique mixture of fiction, ...
Raffzahn's user avatar
  • 218k
23 votes

When did computer manuals and books start using monospace fonts for code, and why?

Could you provide any base for the assumption that using proportional fonts was the most common way before 1980? My experience tells different. Random example with text in proportional and code in ...
Raffzahn's user avatar
  • 218k
22 votes

Why does this BASIC program declare variables for the numbers 0 to 4?

The answer by Raffzahn is very good, except that I disagree that ZX80/81 background is all that important and I also feel he missed one important trick. I personally know most of these tricks from ...
introspec's user avatar
  • 4,152
22 votes

When did "Zen" in computer programming become a thing?

Pirsig's title (ZatAMM) is a quote from "Zen in the Art of Archery, by Herrigel, from 1948. Many programmers, artists, and writers (myself included) find that their best work comes when they are in a ...
Taryn's user avatar
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21 votes
Accepted

Filesystems with versioning

I am not personally aware of any operating system in the entire history of computing ever having had this feature. Siemens BS2000 of the early 1970s may be an example here (*1) with a feature they ...
Raffzahn's user avatar
  • 218k
21 votes

When did computer manuals and books start using monospace fonts for code, and why?

Eating your own dog food Computer manuals for "real" publication, as opposed to just internal use within a company, were typeset using traditional methods. When you are typesetting manually, ...
manassehkatz-Moving 2 Codidact's user avatar
15 votes
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What DOS games used Mode X as described by Michael Abrash?

Many PC pinball games use Mode X, notably Pinball Fantasies, Pinball Illusions and Epic Pinball. Nerdly Pleasures also has a comprehensive post on games using “unofficial” resolutions, which includes ...
Stephen Kitt's user avatar
15 votes

Were any of the books mentioned in this scene from the movie Hackers real?

Stephen Kitt's answers are right, but I'd like to add some context. The writers of Hackers lifted a lot of their jargon directly from the Jargon File, also known in its print version as The (New) ...
Nate Eldredge's user avatar
14 votes
Accepted

Understanding the meaning of the term "Modifying a software program" in a book

In his book The Silicon Jungle David Rothman mentions several times the term "modifying" or "customizing" a software program. Just like today, usage of generic products have always needed ...
Raffzahn's user avatar
  • 218k
12 votes

When did "Zen" in computer programming become a thing?

On a related note, I clearly remember The Tao of Programming making the rounds on BBS in the late 80's and early 90's. According to Wikipedia, it was written in 1987 as a bit of a spoof. A year ...
Geo...'s user avatar
  • 10.1k
12 votes

Filesystems with versioning

In addition to what others wrote: ITS, TENEX, TOPS-20. In ITS, files are named by two strings each at most six characters. The second file name can be a number to specify a version. If you open a ...
Lars Brinkhoff's user avatar
12 votes

When did computer manuals and books start using monospace fonts for code, and why?

In the 1980s, many magazines incorporated source code in the form of photo-reproduced computer printouts, which were naturally monospaced. In situations that didn't use actual computer printouts, for ...
supercat's user avatar
  • 35.7k
11 votes

Were printed manuals for HP PCL or GL ever published?

Books? Manuals! Both are simply the command language for specific HP products, which all had their detailed manuals printed and put in the box. Them becoming de facto standards is history at work :)) ...
Raffzahn's user avatar
  • 218k
10 votes
Accepted

Address of ISR for Interrupt INT 13H

The physical address in the IVT associated with INT31H should be: 13H * 4H = 4CH True But a book I was referring to says that [...] According to them, Physical Address of INT13H is 34H ( 13*4 = 52 ) ...
Raffzahn's user avatar
  • 218k
10 votes

Which computers did Donald Knuth "mix" together to get MIX?

Although on page 124 / Section 1.3.1 of Volume 1 of TAOCP, Knuth only gives the numbers (360+650+…), recall that his indexing is exhaustive. Accordingly, searching for page 124 in the index (easier ...
ShreevatsaR's user avatar
10 votes

Anecdote in Weinberger's Psychology of Computer Programming: is it ARPANET?

Not really, as the IMP implementation was done by a single company (Bolt Beranek and Newman Inc.) at a single location in Cambridge, USA. The contract was awarded to them in April 1969.
Raffzahn's user avatar
  • 218k
9 votes

Unix Haters Handbook - guaranteeing synchronous, atomic operations

Not really an answer to whether there were such systems, but a comment on that section of the Unix-haters Handbook. In the mid 1980s I implemented a (non-Unix, non-SMTP) mail sending agent that had ...
dave's user avatar
  • 35.2k
9 votes

Were any of the books mentioned in this scene from the movie Hackers real?

At least some of them were real. The Dragon book, compiler design: definitely real, a classic textbook. The orange book, computer security criteria: real, never personally encountered it but I ...
rwallace's user avatar
  • 60.2k
9 votes

How does the ‘real mode flat model’ work?

All software sees the full 20bit address space, since there is no distinction between kernel and user land. Flat mode is simply all segment descriptors set to maximum length and base offset 0. This ...
tuomas's user avatar
  • 2,763
9 votes

Documents about timesharing systems, access and resource control and its financials

This answers your question by suggesting some avenues of further research. This is one of those cases where just knowing the right buzzwords helps with the search. You could start by doing some ...
Walter Mitty's user avatar
  • 6,128

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