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Comment Re:As a C programmer (Score 2) 278

Do a locate \.so | wc -l on your system - chances are that the libraries *not* written in C are a rounding error. Pick just about anything remotely useful - chances are it'd more more useful if written in C, because at the very least you can open the executable using dlopen/dlsym and invoke main() with the correct arguments.

Well, personally, I find the fortran written fast fourier tranform (fft) libraries rather useful...
To call from C, even :)

I'm sure there's way to create good C versions too, but the librarary sources might need a lot of macros, and leave a lot more to the mercy of compiler optimizations.

Comment Re:As a C programmer (Score 1) 278

Yes, like memcpy, except memmove (there should be an 'e' at the end for the C89 ANSI compliant name) allows memory to overlap. memcpy can be optimized to be faster since it doesn't have this constraint.

And memmove() can call memcpy() if it determines there is no overlap, so there's not a lot of benefit to memcpy() for other than tiny copies that can be inlined.

Optimizing becomes more challenging when doing copies from unpinned threads on NUMA systems. You want to avoid reallocating a big block between CPUs, while at the same time avoiding big locks.

Comment Re:As a C programmer (Score 2) 278

If you stick to a C-only subset of C++ you can write your library in C++, but at that point why bother with C++ anyway?

Or you could write your library in C++ but put it behind a C interface. Then you can use all of the expressive power of C++ internally, and provide an API that can be called from any language. And it will still be very close to as portable as if it were written in plain C, because we now have decent C++ compilers on very nearly every platform.

Comment Re: This is an Android Problem (Score 1) 161

I wish that there were more phones running plain Android with fast updates.

This article is exactly what we need to make that happen, though ideally we need it to be on CNN, not just Ars. But Ars is a good step. When consumers demand good update policies, manufacturers will provide them. It's a competitive market.

Actually, I think we're further down that road than it may appear. Stagefright was a big kick in the butt for the Android ecosystem. Not because it actually affected any real users, but because it got a *lot* of press. I think many OEMs have realized they need to fix their update problems, because consumers are beginning to care. The problem is that the OEMs product plans for the last few years have not included plans for monthly updates. Planning for that sort of update cycle requires them to change a lot of things in the way they do business. One is closely related to what you mentioned about carrier-specific builds: The OEMs just have too danged many products. It's not uncommon that what appears to the end user as a single model (e.g. Samsung Note 4) is actually one or two *dozen* different devices... each with its own software build. Not because they actually need that many SKUs and not because all of them actually need different software, it's just been easier to do it that way. Now that the pressure to provide updates is being turned up, I think they're looking at how to streamline their product lines and processes to make it more feasible to deliver them. Oh, and they also have to build the cost of the update-related work into their business plans.

However, building phones is a complex process, and device design and planning cycles often run more than two years, so it takes time for changes in approach to reach the market. I think it'll start getting a lot better in the next 1-2 years.

That's why I'm just sticking with Nexus phones.

Me too. Of course, in my case it helps that I get them for free :-)

Comment Re:Missing a big point (Score 1) 585

Of course you didn't talk at all about "handling the current situation" you talked about "self driving" which isn't actually related at all.

I actually don't agree with that, though that's Tesla's position. I don't think semi-autonomous driving is realistic. Once the car can drive itself sufficiently well that people feel safe looking away to text or whatever, they will. Any system that expects that a human will continue paying attention and be ready to take over at a moment's notice is asking for trouble.

Comment Re:74 at time of crash (Score 1) 585

But I still contend that their handling is too poor and this would be extremely dangerous because of this. SUVs (all of them) should be limited to about 65mph IMO because of safety (or maybe even 55). Their handling is just too poor for them to be driven faster. If you want to drive safely at higher speeds, you need a vehicle with a lower center of gravity.

There are SUVs and then there are SUVs. You can't really put a Porsche Cayenne or BMW X6M in the same class as an Explorer.

Comment Re:74 at time of crash (Score 1) 585

You do realize that a Ford Explorer Interceptor has a twin turbo, 365 Horsepower engine? It will easily do 140mph.

The gp post didnt say high speed was an issue, but high speed handling.

Really, even if you can get a Police Interceptor Utility up to 130 mph or so on an air strip, you don't really want to drive it at 80+ if there are curves, hills or slow traffic to avoid.

Comment Re:Location from Wifi? (Score 1) 106

It is very useful. The vast majority of wifi access points have fixed locations (homes, businesses). In my experience (I used my phone with GPS off in an older handset because it wasn't implemented properly and drained the battery), it's nearly as good as GPS - usually able to pinpoint you to about 20 meters.

However, can fixed location be taken for granted in a life and death situation? My phone might pick up an access point of someone who just moved here and brought their WiFi router with them. The databases will still have the old address. So the dispatcher sends a response team to that location because it is "more precise"?

Comment Re:An important thing to note (Score 1) 612

I can't find one either - I moved out of the states ~20 years ago, and I have NEVER paid that much taxes since then, and much nicer (larger) houses.

NJ property taxes are insane, definitely. They've been insane for a long time, though, so I don't think they're evidence of federal taxes being shifted to the state level.

Comment Re:Missing a big point (Score 1) 585

Nice job of focusing on word choice and ignoring the point. The GP claimed that this would be studied and a fix for the current system would be pushed out, making it safer. My point is that I don't think the car has the sensors needed to handle this scenario, so it's not possible to push a fix to the current system.

Comment Re:Thanks to (Score 1) 364

How about making modded-up ACs a bit more visible?

I was thinking of giving an automatic +1 boost as soon as a moderator gives a +1 to it. That is, they end up at +2 after a single moderation. Less waste of mod points for the good ACs.

Please think it through. Many of the trolls and spammers already use sockpuppet accounts. With your proposal, they'll have a much easier time upmodding themselves (and in a few cases, each other). Two others would have to spend a modpoint to undo that - mod points that could better be used to promote good postings.

Comment Re:Location from Wifi? (Score 1) 106

GPS does not work better with WiFi enabled

Actually, your GPS receiver can pinpoint your location more rapidly if it has a good approximate location to start with, which it can get from Wifi location. If your GPS receiver had to start from scratch (no assumption about initial location), it could take multiple minutes to locate you because it has to find and identify multiple satellites, and listen for a full 30-second cycle from each. With a good location estimate plus an already-synchronized clock, the GPS receiver can refine your location in a few seconds.

So GPS does work better with Wifi enabled. And, as you said, location services can use Wifi even when GPS isn't available. In cities Wifi can be much better than GPS because unobstructed views of the sky are hard to come by, and the Wifi AP density is high.

Comment Re: Compromise (Score 1) 364

Are trolls and spammers really a problem? They start at 0 and often go down to -1 fairly quickly. You only see them if you opt to, by default they are hidden.

Well, yes - if you hide the -1s, you also hide a lot of good comments that have been downmodded by people who abuse the moderation system.

Also, many of us score boost long (and hopefully thoughtful) comments. Which, unfortunately, also boosts many spam posts. Personally, I think that's an acceptable price to pay.

What would fix the troll and spamming problem is to not rely on automation, but having actual people go through and auto-hide those posts. Implement a -2 that can only be set by /.
But don't delete them.

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