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Comment Re:the Open Group needs to up its game (Score 2) 46

POSIX has just fucked this up.

I mean, consider the simpler goal: deprecating select(). select() is completely unusable in nontrivial applications, or in any library that might simply be in a process space that might have more than FD_SETSIZE file descriptors -- with the failure mode being memory corruption in practice, because who bothers checking FD_SETSIZE?

The problem? POSIX hasn't even managed to incorporate ppoll()! So, if you're wanting to portably combine signal handling and FD monitoring, you're forced to use pselect(), and so we can't simply say that nobody should ever use select().

And there really is no longer an argument for it anymore. There used to be a performance argument, but it's gone now: at FD_SETSIZE's usual value of 1024, a poll() of size 1024 in linux uses only 64KB. A copy of 64KB on modern computers is going to be dwarfed by the overhead of doing a syscall.

Comment Re:New jobs will be created. (Score 1) 266

You are, in fact, wrong -- quantum computers aren't as powerful as you think they are.

The problem is that for what you describe as "root finding" a naive quantum computer only gets a quadratic speedup. Your 256^1000 possibilities still take on the order of 256^500 steps to search.

With that said, if you can build a computer around a closed timelike curve ("time travel") it would be powerful enough to do what you want. The idea here is that the computation starts off by receiving a value from the future, call it N, which it should test out to see if it is a solution. If N is the solution it reports back N at the end, otherwise it reports N+1.


Disney Pulls a Reverse Santa, Takes Back Christmas Shows From Amazon Customers 418

Sockatume writes "Since 2011, Amazon Instant Video has sold a series of Christmas shorts from Disney called 'Prep and Landing'. Unfortunately this holiday season, Disney has had a change of heart and has decided to make the shorts exclusive to its own channels. The company went so far as to retroactively withdrawn the shows from Amazon, so that customers who have already paid for them no longer have access. Apparently this reverse-Santa ability is a feature Amazon provides all publishers, and customers have little recourse but to go cap-in-hand to a Disney outlet and pay for the shows again."

Comment Re:Body hacking (Score 2) 86

while the extra centripetal acceleration draws blood out closer to my fingertips.

I think you mean "centrifugal force". Note that a centripetal acceleration/force would be pulling your blood back inwards from your fingertips; you're looking for the equal and opposite force that is pulling the blood away.

Physics teachers who say that there is no such thing as centrifugal force are lying; it is every bit as real as gravity. It is a white lie, with the point of avoiding accelerating non-inertial reference frames. Such physics classes will show that centrifugal force is entirely explained by inertia in a reference frame undergoing centripetal acceleration. That's great.

Here's the problem: those same classes will regularly describe gravity as a force. The thing is, once you study general relativity you realize that gravity (and in particular the 9.8 m/s^2 acceleration you feel downward) has exactly the same explanation; space-time is curved by the mass of the Earth such that the surface of the Earth needs to accelerate upwards at 9.8 m/s^2 in order to remain "in place".

In other words, centrifugal force is entirely as real as gravity. If it is centrifugal force that makes your blood move out, don't be afraid to say it.

Comment Re:Trading term (Score 1) 91

Putting money in every paycheck is great and exactly the way to go, but isn't "dollar cost averaging". Dollar cost averaging is something else and entirely bogus.

Suppose you get $120K. DCA advocates would tell you to invest, say, $10K of it every month into your preferred asset allocation, rather than investing it all at once.

On the other hand, suppose your cat walks over your keyboard while you're logged into your brokerage and sells $120K of stock. Do you invest it $10K at a time or do you just reverse your transaction immediately? Hopefully it is obvious that you do the latter -- but this scenario is exactly equivalent to the first one.

Comment Re:And it's in Japan (Score 2) 268

If you're going to do a comparison like this you really need to count just the 23 special wards (14,485 per square kilometer). Tokyo the prefecture-equivalent "metropolis" includes a lot of areas which are essentially suburban sprawl west of Tokyo -- the Tama area. I don't think anyone would really consider, for example, Hachioji to be part of Tokyo the city, but it is a substantial fraction of Tokyo metropolis -- and if you're coming up with a number as low as 6,810 you're including it.

This is complicated by the fact there is no longer a government for Tokyo City, which is what used to be the 23 wards. The wards themselves are cities, somewhat comparable to a more independent and smaller form of NYC Boroughs. Conversely, Tokyo metropolis would be something like a separate State of New York City which includes both the Boroughs and Long Island and a couple of small islands in the Caribbean.

With that said, there's no ward of Tokyo which is as dense as Manhattan. mostly because there aren't a lot of tall buildings. The technology to build earthquake resistant skyscrapers is relatively new compared to a lot of the construction.

Comment Re:Don't Knock it (Score 1) 93

This is a standard strategy, which I've seen referred to as "turboing", which is particularly effective when standard channels fail. The key point is that, really, you're not trying to speak to senior management, you're trying to speak to the PA of someone in senior management.

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