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Comment Re:Of course it is. (Score 1) 769

Thanks!

There are a lot of historical artifacts in command-names; there was a great paper called A Unix Reader (I think) that talked about some of them, and had, e.g. the very first Bourne Shell manual page, showing how the pipe syntax evolved.

Comment Re:Of course it is. (Score 1) 769

indeed it could be a list of pretty much anything; go to /proc and do ls, and you get a list of processes... go to /dev and you get a list of devices.

I don't think it's really a big deal, I just wanted to take time to explain a bit more about why it was called "ls" rather than the more jargonesque "dir".

Comment Re:Of course it is. (Score 1) 769

Dir is a sensible abbreviation of a word that you’d normally use to describe a list of names? The word you used yourself is "list". However, the function of ls is to list information about one or more files, not to print a directory. For example, ls myfile, prints information about "myfile" regardless of whether it's a filr or directory. So, there's a reason for the name too. The original main file commands, like ls, chdir, dsw, pwd, mkdir, had a pattern to them: the first two consonants for a single word (ls), with an abbreviated second word appended if appropriate, such as mkdir for "make directory", chdir for "change directory", and abbreviations for others, such as dsw (delete from switches, long replaced by rm for remove). Over time some of the commands were shortened further, so that cdir became cd, using the first letters of "change directory." A lot of this need for terseness was because the original Unix interface involved teletype machines, a sort of computer-driven steampunk typewriter, and they were erlatively slow and painful, especially over 110 baud dialup lines (yes, 110, not 110K).

Having said that, by 6th Edition Unix there was a short "quick reference" document that listed the most common commands, and something like that is clearly needed on Linux, to help people find the most important tools. It doesn't matter how well they're named if you can't find them!

Comment Simplify the Law (Score 1) 278

I run a Website for images (mostly) and text scanned from old books. When Google books started I thought at first I could just give up, but it turns out that the quality is so low for Google books that http://www.fromoldbooks.org/ and other sites like it continue to perform a valuable service.

I have had to spend a lot of time researching copyright law. I started out believing wikipedia, hah! And there are tons of Web sites with myths about copyright, e.g. that anything published before 1923 anywhere in the world is out of copyright in the US. Did you know that the UK copyright act has an exception specifically for works created in a hovercraft? Or that anonymous works have different copyright terms than ones that are credited, but e.g. if the name of a photographer becomes known (or knowable through any public means) after publication, it gets the longer term? And there's no central registry.

We're all getting screwed out of our heritage when a private corporation can control the world's library. To stop this, copyright law must be made simpler, and there must be online searchable registries. Copyright must eventually be harmonized between all countries, since digital information knows no borders. But it must be harmonized in such a way that some currently cpoyrighted works fall out of copyright, and as few as possible works that are out of copyright are placed back into cpoyright. The difficulty is that in corrupt regimes like the US, companies can pay politicians for their election campaigns, and hence special interests predominate politics. And I have idea how to end that corruption, of course.

Comment Re:Open X Alliance (Score 1) 144

One problem with all this that I see is that the quality seems awfully spotty, but usually pretty low. Which means one day it'll have to be done again. Google's main goal is to have as much content as possible, so as to drive advertising revenue. Here's a short extract from a Google book (try it, look through the text of them), showing how well Google is preserving our shared heritage:
[[
SAAVEDRA-FAXARDO (OfBooiBa), a SpMishfipolU

ileal and moral writer,' was bora* May 6^ l58e^>atiAlgaMMm

iittbe kiDgddm of 'MiUQia, i^ndslttdiedal^SslanMieoai' lA

1606, he'went toRome tei^sect^taiy to tiie>icahliAA<tes-

par de Bdfgia,-who was appointed Spaaisbaaabaaiadoi^i^e

the pope,-^ and assisted inahe^xionBtav^'of tl6ai.atidi1i6(l8$

Held for the eleeHoti of Ae popett Gregovy JiV. awd^Uas

baaVfn. For these aervices Saaaedra^wtts rewarded wiril

a^ eanorrry in the* ehifrdi of St:>Jatnes, attbeegb be kmi

ifever tikei^. prieitVoniera. iBem^time aiier Ae was #pu

{loiiited agent freer 4be cobrt^of vSpaia^lit^eaiey.aiidt kii
]]

Got that?

Comment What about the Quality? (Score 1) 160

The quality of scans from Google Books seems very low to me; much lower than I'd use on my own Web site, http://www.fromoldbooks.org/ - it's not uncommon for pages to be missed, and in one 19th century mechanics textbook I was looking at, the low scan resolution meant that most of the line drawings and diagrams vanished entirely.

It's obvious to me that the Google work will need to be done again by people who care about the content. Note, by the way, that most flat-bed scanners destroy the binding of books, although some people are now using e.g. a Canon 5D full-frame-sensor SLR camera instead. For illustrations, some simple mathematics (and experience) shows 600dpi to be an absolute minimum for a scan of an engraving, with fine steel engravings needing at least 1200dpi (I used 2400) in order to prevent the lines from being aliased into a blotchy gray. This is much higher than the Canon SLR gives, but Betterlight have a 500 megapixel backend to a medium-format professional camera that would give enough resolution for a good digital fac simile, and e.g. the University of Wisconsin uses that sort of equipment. But it's much slower and hence more costly, and the files are huge.

Here's a fragment of text from a Google book I've been working with:

        ALLEN ^Anthony), an English lawyer and antiquaiy,
        was born at Great Hadbam in Hertfordshire, about the end
        of the seventeenth century, and was edu<?^ted at ffton;
        whence he went to King's college, Cambridge, and took
        his bachelor's degree in 1707, and his master's in 1711.
        He afterwards studied law, was ciiJI^d.to' the bar, and bjr
        the influence of Arthur OnsloW^ speaker of the house of
        commons, became a roaster in chancery. His reputation
        as a lawyer was inconsiderable, Jbiut he was Esteemed a good
        classical scholar, and a man of Wit: and -convivial habits.

The version I have at http://words.fromoldbooks.org/Chalmers-Biography/a/allen-anthony.html (I am still working on these) is based on scanning done at the University of Toronto, combined with four other digitisations, including two apparently independent ones by Google, both of the quality demonstrated here.

It might turn out that it would have been less work to have scanned this 32-volume encyclopedia myself (I have a copy) and so the OCR with commercial software that works 1,000 times better than Google's, but, for reprints, the important thing is the quality of the scanned images, not the OCR - and there too, the Google scans are really sucky.

Image

Universal Design for Web Applications 85

Michael J. Ross writes "Two decades ago, Web usage was limited to a single individual (Sir Tim Berners-Lee) using the only browser in existence (WorldWideWeb) running on a single platform (a NeXT Computer). Nowadays, billions of people access the Web daily, with the ability to choose from over a dozen browsers running on desktop computers, laptops, and a variety of mobile devices, such as cell phones. The number of possible combinations is growing rapidly, and makes it increasingly difficult for Web designers and developers to craft their sites so as to be universally accessible. This is particularly true when accounting for Web users with physical and cognitive disabilities — especially if they do not have access to assistive technologies. The challenges and solutions for anyone creating an accessible website are addressed in Universal Design for Web Applications, authored by Wendy Chisholm and Matt May." Keep reading for the rest of Michael and Laura's review.

Comment Re:Similar to Windows hate? (Score 1) 503

A teletype such as the popular ASR-33 was a printing device, and had no difficulty with descenders. It worked a bit like a golf-ball typewriter: the letters were embossed (in reverse) on a cylinder, which moved into position and then struck an inked ribbon which then hit the paper. The embossed letters came from an analog process, and could be any shape. Parentheses, for example, and the comma, typially went below the baseline.

They could go at about 10 characters per second, for what it's worth, and I still remember the noise they made :)

Comment Don't worry about it (Score 1) 569

A knowledge of programming in general, an understanding of algorithms, of complexity and basic security issues, will put you ahead of a lot of "consultant programmers" I have met.

Recruiters generally think C and C++ are the same thing, and so do HR departments.

If you enjoy what you do, and are good at it, you'll get better and be an asset to any slave-farm^H^H^H^H^Hcorporation.

Contribute to an open source project or two, perhaps.

Having said that, what university is teaching computer science students only three languages, and all procedural? You should know at least one fuctional, non-procedural language, e.g. pure scheme, ocaml, xslt or xquery, prolog, would all be candidates, even if your university forgot to teach lambda calculus :D

The value of a declarative language isn't that you will get a job programming in LISP (although you might) but rathar that it gives you a different toolset, a different way to think about problems that turns out to be useful in a lot of other places.

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