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Comment Re:This is stupid ... (Score 4, Informative) 143

Leap seconds are an artifact of our timekeeping system, and actual physical properties of our orbit.

The latter we are stuck with but the former is something humanity has the power to change. There are basically three choices.

1: Disconnect the civil time second from the SI second. Allow the civil time second to vary slightly to match the mean solar day.
2: Allow civil time to drift relative to solar time
3: Make periodic adjustments to civil time to keep it close to solar time.

Each choice hurts different people. Choice 1 hurts anyone who needs to convert between civil time and "atom time". Choice 2 hurts people who rely on civil time as a navigational aid and future historians. Choice 3 puts a rarely excersised special case into computer systems leading to systematic failures.

Comment Re:Let me get this right. (Score 1) 151

It varies.

In the old day each new console was a very different system that was basically totally incompatible with it's predecessors, if you wanted to keep playing your old games you had to keep your old consoles around. Sometimes a game would be re-released for a newer console but this was the exception not the rule. If a game was re-released and you wanted to play it on your new console then yes you did have to re-buy it. Often such games were packaged together into compilations for the re-release.

The playstation 2 broke this trend being able to play games for the original playstation (from their original disks, no need to re-buy) with no obvious issues. The playstation 3 was supposed to continue this but the support hardware for this feature was removed in later PS3 models (some intermediate models removed some of the support hardware and replaced it with crappy emulation, later models removed PS2 support completely) to cut costs. I have no idea about the playstation 4.

Original wii models had support for gamecube games to be played off their original disks but this was removed in later models. The wii-u similarly supports wii games (but not gamecube games) off their original disks. With the wii ninitendo also introduced something called the virtual console which allows playing many of the games for older consoles (both nintendo and otherwise) but you have to re-buy them.

On the MS side the xbox 360 could play some games for the original xbox. You could use the original disks (didn't have to re-buy) but you did have to have a hard drive and internet connection.

I belive sony and MS are doing something similar to the virtual console but I haven't investigated the details. I'm also not sure what is going on with the PS4 and XBONE as I lost interest in consoles before they came out.

And yes many people do build shelving around their TV to support their collection of games consoles.

Comment Re:Um... (Score 2) 274

I suspect the politicians and bankers dream about doing that but realise that if they did it all at once they would piss off the general public too much.

So instead they play the long game. They do not issue larger banknotes to keep up with inflation (and in the case of the US they actually stopped issuing existing denominations). They put in place reporting requirements for large cash transactions which again they don't update to keep up with inflation.

Comment Re:Virtulize? (Score 1) 406

As I understand it "system crash" doesn't mean planes falling out of the sky but it does mean massive disruption if it can't be recovered from quickly. They need the automated systems to manage the density of takeoffs and landings at busy modern airports. If they lose that automation then flights have to be held/diverted/cancelled to keep the number of plane movements in the problem to a level they can manage manually.

Comment Re:Interesting question for science oriented langs (Score 1) 304

For example, the union of two spatial domains, should it be "c = union(a, b)" or "c = a \{insert big U symbol here\} b",

There is really two seperate but related questions here

1: ascii VS unicode. Unicode looks nicer for equations but is less portable and is harder to enter. There is also the problem that programmers like to use fixed with fonts which gets more complicated with unicode.
2: function style VS operator style. IMO operator style makes complex formulas much easier to read than function style but it's useful for a programmer to be able to tell the difference at a glance between variable/function names and operators.

One option could be to allow use of either unicode or ascii representations for operators. For example you could establish a convention that extended operators expressed in ascii started and ended with a dollar sign (or some other character, I picked the dollar sign because it doesn't seem to be used for anything in python). So the union operator could be written as either $u$ or as the unicode character for union. The circle plus operator could be written as either a unicode circled plus character or as $+$ and so on.

You could then provide a tool to convert between the pure ascii representation and the unicode representtion.

Comment Re:It's all squiggles (Score 2) 304

The strength of C++, for example, is that you can define your own operators and how they operate upon particular data structures

IMO the weakness of C++ is that you can define how the provided operators work on custom types but you can't create new ones.

The result is that the set of provided operators gets overloaded to have very different meanings.

Comment Re:So AMD called their Hyperthreading a CPU core? (Score 1) 311

Meanwhile Intel leads people to believe that "i7s" are the best processors and then slaps that same brand on 4-6 core desktop processors, 2-4 core mobile processors (clocked a bit lower than the desktop ones) and 2 core ultra-mobile processors (clocked much lower than the regular mobile ones) . By doing this they milead customers into thinking they are not sacrificing performance by buying a small/light machine.

AIUI advertising is about misleading customers as much as possible without stepping over the legal lines. Afacit unless they promote hard numbers or direct comparisions that are demonstratablly wrong they generally get away with it :(. Unfortunately I don't think vauge headlines like "maximum performance" or references to 8 cores (this very discussion on /. shows there is no agreement over what constitutes a "core") are enough.

Comment Re:i5, same thing? (Score 1) 311

i3, i5, and i7 represent "good", "better", and "best" respectively. That's it.

Worse still they only represent that within a given generation and within a particular "market segment".

My theory is they designed this naming scheme to deliberately mislead customers into thinking ultraportables could be as powerful as desktops while the reality is an ultra-mobile i7 is less powerful than a desktop i3.

Comment Re:Try not to be misguided (Score 1) 47

The problem with the lock icon and similar things is it arrives too late. By the time the user sees it they have already interacted with the server and potentially sent it sensitive information.

Consider for example a login form on that submits the login details to .

Comment Re:It's not the Earth's fault (Score 1) 291

Leap seconds are a human creation in an attempt to unify atomic time with planetary movements.

There are basically 3 options.

1: Tie civil time to the SI second, have 86400 seconds in a civil day and accept that the civil day will slowly drift relative to the astronomical day.
2: Have 86400 seconds in a civil day but decide that the second of civil time can vary in length from the SI second and adjust the civil time second so that .
3: Tie the civil time second to the SI second but periodically make adjustments through having civil time days that are not 86400 seconds long.

Each option is bad for different people.

Option 1 is likely to be confusing for future historians and astronomers as they have to deal with an offset between civil time and earth time that varies depending on when the data was collected.
Option 2 is bad for people who need to interface between systems that work with civil time and systems that need to measure elapsed time very accurately. e.g. people who have their own atomic clocks or people who rely on GPS for getting the time.
Option 3 is bad for IT systems as it introduces a rare special case which can cause a lot of systems to fail at once when their implemnentations of that special case differ.

Comment Re:Err, no. (Score 1) 149

Supporting lots of different magnetic disk formats is expensive both financially and in terms of considerations like bulk and weight. Each one needs a physical mechanism that while similar in principle is different enough in details that you can't generally use one mechanim for multiple formats unless the formats were specifically designed for it.

On the other hand with barcodes the same camera can be used to read all of them. Supporting more formats is just a little bit of extra software.

Comment Re:Element14 doing sme slashvertising (Score 1) 93

Q. What's the difference between an "Official" customized Raspberry Pi and any other customized Raspberry Pi?

It seems the difference is that they have the design files and the authorisation to do customisation at the pre-manufacturing level. Anyone else who wants to customise has to work with the completed boards.

Comment Re:So does Australian intelligence agency ASIO (Score 3, Informative) 52

As I understand it constructing a rouge certificate by attacking secure hash functions requires either

1: a preimage attack on sha1 with chosen prefix and chosen suffix. This seems unlikely in the forseable future even for MD5.
2: a collision attack with distinct chosen prefix and common chosen suffiix combined with a CA that has poor procedures that allow the purchaser to predict what their certificate metadata will be. This has been demonstrated in the past for MD5 (google "md5 collisions inc"). Noone has yet demonstrated a full collision for SHA1, let alone a distinct chosen prefix collision.

As of right now I would class this as a lower risk than the risk of some CA simply issuing an end entity certificate to someone other than the legitimate owner of the domain and/or issuing and intermediate certificate to the attacker. Of course attack techniques are improving all the time so it's prudent to move sooner rather than later. Chrome is being a bit alarmist because they know if they don't then people won't move until it's too late.

Radioactive cats have 18 half-lives.