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Comment Re:Oh, not again. (Score 1) 401

As a practical matter, there's a widely used program that tries to solve the halting problem by formal means - the Microsoft Static Driver Verifier. Every signed driver for Windows 7 and later has been through that verifier, which attempts to formally prove that the driver will not infinitely loop, break the system memory model with a bad pointer, or incorrectly call a driver-level API. In other words, it is trying to prove that the driver won't screw up the rest of the OS kernel. This is a real proof of correctness system in widespread use.

The verifier reports Pass, Fail, or Inconclusive. Inconclusive is reported if the verifier runs out of time or memory space. That's usually an indication that the driver's logic is a mess. If you're getting close to undecidability in a device driver, it's not a good thing.

Doesn't the fact that it includes an "Inconclusive" category pretty much mean that it absolutely does not try to solve the halting problem?

The halting problem doesn't state that you can never determine if any specific algorithm halts or not, just that there exists some algorithms which will be inconclusive for any finite bound on the time used to determine if it halts or not.

Comment Re:PDFs are programs for printing 2D objects (Score 1) 258

A pdf file is a program, written in the postscript language, directing a 2D printer to create some 2D object. I can't print copies of someone's book and sell them without permission based on the argument that the book is the output of the PDF program.

I don't see how adding an extra D changes that.

It doesn't. But not all pdf's are copyrightable.

http://www.copyright.gov/help/faq/faq-protect.html

You can't print someone's book because the book is a work of literary authorship. If you get a non-copyrightable pdf, such as a simple list of facts or ingredients, then you can print that and sell it. We will likely see something similar happen in the 3D printing world.

At issue here is not whether or not the printer has two dimensions or three, but rather if the underlying object would be considered an original work of authorship. Probably not.

If you compare this to the fashion industry, for example, where a designs for clothing are *not* eligible for copyright. The fashion industry has responded to this by elevating trademarkable labels to be elements of fashion themselves. I can take a Tommy Hilfiger t-shirt and produce another shirt with its dimensions exactly, but I can't put that logo on it.

Comment Re:#1 - Not managing the pointers and memory yours (Score 1) 394

#2 - Initialize all variables to known values. int i; doesn't cut it. int i=0; does.

True dat. Lots security pitfalls here too -- not just garden variety bugs.

This is a pet peeve of mine. It's very bad advice to throw in meaningless initializations. If a variable has no meaningful value, you want tools like valgrind to be able to recognize this and catch code that tries to use this value. If you set it to 0, but then don't mean that variable to be read without being set to something else first, you've done yourself a disservice.

Comment Re:B-b-b-but I thought Apple was a marketing compa (Score 1) 346

Basically it looks like we don't need any higher resolution than what the iPhone and others have achieved, anything more would be pointless.

Unless you happen to have a $5 pair of magnifying eyeglasses that is.

The biggest problem with viewing web pages on a cell phone is that you can't see enough pixels at the same time. If you want to keep a 1920x1080 display in your pocket, you need to go beyond retinal and use a lens to magnify it.

Comment Re:Games too (Score 2, Informative) 595

I am not seeing any phone that currently supports the whole flash experience: http://www.adobe.com/mobile/supported_devices/ Just the Flash Lite option.

That list is a little out of date. The Nokia N900 runs the desktop version of Flash 9.

On the other hand, many flash games require more CPU than a mobile device can really provide at the moment.

Comment Re:It depends (Score 1) 390

It leads me to the following question: "is there a place where we can buy ebook in a non-crappy drm encumbered format ?"

I use Fictionwise, which is now owned by Barnes & Noble. They have a very wide selection of what they call "Multiformat" ebooks that are available without any DRM at all. Although they do also sell "secure" ebooks, the web site makes it very easy to filter these out and only browse titles that are available without DRM.

Comment Re:Possibly another reason (Score 1) 306

The bigger *any* organization gets, the less efficient it becomes.

Is that why Walmart has to charge such high prices? To cover all that inefficiency?

It's not size that leads to government inefficiency, it's a lack of competition. If you could pick one of three governments to pay your taxes to, you'd see efficiency shoot way up.

Comment Re:Repeat after me: Death to DRM. (Score 1) 437

The choice is not between "content with DRM" and "content with no DRM", but "content with DRM" and "less content with no DRM".

That's only true in the short term. Those who advocate boycotting DRM infected media are concerned with the long term. If enough consumers avoid products with DRM, then the market will adapt and cease to sell works with DRM and content with no DRM will become available. That's how boycotts work.

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