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Comment Re:Because 1/0 != 0? (Score 1) 1067

Exception yes, NaN no. NaNs suck. An exception takes you right to the problem, or close to it. NaN spreads over your variables like kudzu, since any calculation involving it results in NaN. Sure it tells you there's a problem, but by the time you see it, half your variables are NaN and you're left trying to figure out where it came from.

Comment Educational Purposes (Score 1) 68

They said it's for educational purposes. The point isn't performance -- you're not getting that from RasPis. The point is either to train people on supercomputer programming or to test supercomputer programs on smaller data sets without using time on a real, expensive supercomputer.

I could see building a smaller scale one of these myself as a way to learn MPI.

Comment Re:Overblown Hyperbole (Score 1) 107

Bluetooth (depending how they implement pairing), CD and synced Android device sound like viable attack vectors. None of them are instant remote control with no action by the owner, but they're all quite usable.

Bluetooth: If it makes you enter a code displayed on the other device to pair, that's more secure. But if the car just displays something like "$DEVICENAME Do you want to pair with this device? [Yes] [No]", it's not really. Either someone will habitually click yes, or can be enticed to through careful choice of the device name.

CD: Pretty straightforward. Hand your enemy a CD when he's about to get into his car. Tell him it's a song, lecture or whatever you wanted him to listen to. CD goes in, malicious file does its thing, car crashes. Sure you could sabotage the car itself, but what car crash investigator is going to think to check the CD that was playing for custom-made viruses?

Paired Android device: Similar deal, but even better. Trick them into installing an app modified to contain malware. They'll have their app and be none the wiser. The malware lets you see when and where he's driving (GPS+accelerometer), and you can then interactively take control of the car when you please. Better still, the malware could erase itself from the phone just after the crash, so even if they think to check for that sort of thing, there will be nothing to find.

Comment Re:Here is the letter Lenovo sent out to everyone (Score 1) 266

This seems awfully late to have bought a T420 new. I got a factory-refurb T440p in July 2014. It came pre-loaded with Windows 8.1, which I still have on it and it has never had Superfish. They also claim that they didn't put Superfish on any ThinkPad branded laptop.

If yours came with it, someone somewhere installed the wrong image or additional-software bundle.

Comment Re:Hardware ICE - JTAG (Score 1) 215

Nah. This scheme is designed with hardware-based attacks in mind. From the sound of it, unless you're going to put taps on the actual CPU die this will fail.

The solution is software. Run it in an emulated CPU and dump the emulated TLB whenever you like. Or, there has to be SOME unencrypted code at the start that finds the key and sets up the rest of the nonsense. I expect this part to be heavily obfuscated using traditional techniques that can be deobfuscated with operand tracing and the like. Reverse this and you have the encryption algorithm and key.

This WILL fail but it'll probably make for a few games that take a while to crack, and a few interesting crackmes.

Comment Re:bang on the tv too (Score 1) 304

I had a Trinitron monitor in the '90s that needed frequent percussive maintenance. A metal whisker has bridged heater to green electron gun inside the tube. The result was green running at maximum intensity all the time, even during horizontal and vertical blank. A good sharp whack would temporarily dislodge it.

Comment Re:Wrong conclusion (Score 1) 269

>Try to find another mp3 player with massive storage
>Any Android device.

Last time I looked for such a thing, my choices seemed to be:
A. Small device with fairly small storage. This is getting better lately, with phone builtin storage growing, but I still haven't seen anything as small as an iPod Classic offering anything like 160 GB. However, the phones that have anywhere near enough storage are also rather large.
B. 5-9 inch tablet. Need I say more? If I wanted to browse the web and watch movies on it this would be awesome, but I want a pocket sized device to listen to music on. I don't care if it has a high resolution touchscreen; if it doesn't fit comfortably in a pocket, it's useless to me.

>an excellent user interface

This is something you're not going to get on an iPod Classic either. I thought the UI was pretty nice until I installed Rockbox on a Sansa Clip+. It has a truly tiny 2-level monochrome OLED display and a generic selection of buttons and a CPU that can barely emulate classic GameBoy at full speed. But with Rockbox it has so many more functions than my iPod Classic, which can't run any unofficial firmware due to code signing. I can edit playlists with much greater ease. I can enqueue songs without disrupting the current playlist. I can save custom playlists with names other than "On The Go Playlist 5". I can search and navigate my music library much more effectively. And the big one: I can connect it to any Windows, Linux or Mac and access my music library like on any disk.

>good to excellent build quality

Sure, the Clip+ has a plastic shell, not Apple's anodized aluminum. It does seem to be pretty sturdy though, apart from the clip -- it broke off after a couple years, I dremeled off the remains of it, drilled a couple little holes and now have it on a nylon cord I wear around my neck. It's gone in water a few times as well. I blew the water out of it as best I could and let it sit for a half hour, and it doesn't seem to be any worse for the wear.

Downside of my trusty little Clip+ is that it's 4 GB plus whatever MicroSD I can stick in it. When I can get a 128-256 GB MicroSD, I'll truly have a replacement for the iPod Classic.

Comment Re:What's happening to Linux? (Score 1) 257

Partially agreed. For overly verbose languages like Java, an IDE is really helpful. You can make some nice macros in vim, but you can't quite match with a good IDE can do. Still though there are times I save, close, and open in vim so I can efficiently do some wacky transform with regexes and macros.

For C though I just use vim all the way. And with a few plugins, it can become a pretty good C IDE.

Unlike an IDE, vim can be made to do just about anything. I've used it before to take an image of font characters in a grid saved as an ASCII .pbm and separate them into C arrays for each character in the font.

Comment Re:Upgrade to Windows for improved stability! (Score 1) 257

Crap USB peripherals should not take down the system unless the user has also installed crap drivers that break things, in which case there's really not much to be done about it. When I connect a defective or rubbish device, I expect the port to cut power if there's a short, or the "Windows cannot detect this device" balloon or similar Linux console message. If the cord on a mouse is starting to fail, causing it to disconnect randomly, I expect either intermittent functioning, frequent BADONK noises, and maybe a console message about a port being disabled for some seconds due to a device bouncing.

Then again, it's possible that his USB host adapter is at fault, and not the mouse or any driver. This would be my guess if nobody else is able to reproduce the crash when plugging and unplugging devices.

Fear is the greatest salesman. -- Robert Klein