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Comments

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Heartbleed Coder: Bug In OpenSSL Was an Honest Mistake

Lisandro Re:Not malicious but not honest? (446 comments)

Ditto. Writing a custom malloc is insane for a sensitive security library like this... specially when it is done so carelessly.

The fact that OpenSSL won't even work using regular malloc() suggests that there're more issues waiting to pop up here.

about two weeks ago
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Theo De Raadt's Small Rant On OpenSSL

Lisandro Re:Summary. (301 comments)

Think it this way. Using the current memory management implementation on OpenSSL adding a test case for the exploit would not have triggered any issues. At all. Using a regular malloc() on any half-decent *nix system would've immediately triggered an alert when run through Valgrind or similar.

Reusing memory with a freelist on a sensitive library like OpenSSL is a problem waiting to happen.

about two weeks ago
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Theo De Raadt's Small Rant On OpenSSL

Lisandro Re:not developed by a responsible team? (301 comments)

Writing a custom malloc on a security sensitive product like this is a problem waiting to happen, specially when you do so carelessly. Freelists? No memory cleanup? Theo's right here.

about two weeks ago
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Did Facebook Buy Oculus To Counter Google Glass?

Lisandro No. (108 comments)

Facebook bought Occulus because it has more money than it knows what to do with these days.

about a month ago
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Mathematician: Is Our Universe a Simulation?

Lisandro Re:Some possible ways (745 comments)

Again, wrong. You're (purposely?) mixing up redefinition of results vs the redefinition of algebra. Redefining the algebra behind division (and all other basic operations in the process) is a valid approach to tackle the division by zero problem. Redefining its result alone is not. And, incidentally, none of those two will do you any good with IEEE numbers.

You simply can't just say " x / 0 = 42 " without redefining division, substraction and multiplication. And all other operations in the process.

division by zero is sometimes undefined, but there is no natural reason for it to give an error. For example, IEEE defines floating point division by zero as infinity, whereas dividing an integer by zero is defined as an error.

The example is wrong since IEEE does not define division by zero as infinite to be a valid result. And, under the algebra rules used by IEEE floats there IS a very good reason for it to give an error. This is not a philosophical discussion; you don't need to sit down with a Fields medal mathematicians in order to understand why the above statement is incorrect.

about 2 months ago
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Mathematician: Is Our Universe a Simulation?

Lisandro Re:Some possible ways (745 comments)

You're right, thanks. I was of course refering to division under linear algebra, but there are indeed other algebras where division by zero yields a meaningful result.

about 2 months ago
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Mathematician: Is Our Universe a Simulation?

Lisandro Re:Some possible ways (745 comments)

It can be defined at any time in any way. You could define it as always equaling 42.

No, you cannot. It is not only not useful, it breaks math - you can't arbitrarily define a division result without breaking all related operations, like multiplication and substraction.

What you can do, as maxwell demon correctly pointed out, is to extend algebra so division by zero makes sense. This means, of course, to redefine all basic operations, and since IEEE floats are built around basic linear algebra there is a natural reason why division by zero gives errors: it its either indeterminate or has no solution. When IEEE defined division by zero as infinity was not to provide a valid solution for it but to ease error handling afterwards.

You should consider toning down the patronizing. Your original statement is incorrect.

about 2 months ago
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Mathematician: Is Our Universe a Simulation?

Lisandro Re:Some possible ways (745 comments)

Division by zero is mathematically undefineable.

If A * B = C and C / B = A, you can't have B being zero without C being also zero (in which case the equation is valid for all values of A, a.k.a undefined). For every other value of C the equation has no solution. The only reason IEEE defined division by zero as infinity was to make errors easier to handle.

about 2 months ago
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Fire Destroys Iron Mountain Data Warehouse, Argentina's Bank Records Lost

Lisandro Re:So they eliminated their debt with a fire? (463 comments)

"Some speculative monetary moves" = buying $1,500,000 USD at a 8,70 ARS rate when the official rate was 8,50 and climbing fast. If buying 1,500,000 accounts as "speculation" from a huge oil company we're in deeper waters than we thought.

about 2 months ago
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Five Alternatives To Snapchat

Lisandro Oh, no! (94 comments)

Not Snapchat!

about 4 months ago
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Ask Slashdot: What Are the Books Everyone Should Read?

Lisandro Not "must reads" per se, but books i've enjoyed... (796 comments)

...in no particular order.

"Passage", by Connie Willis. Yes, "The Doomsday Book" is probably her better known work, but "Passage" is immensely gripping. A light read but quite thought provoking.
"Contact" by Isaac Asimov. Forget the movie (which wasn't half bad either); the book is great and focuses more on the characters' religion and spirituality. I've recommended it to a number of relatives who hate sci-fi and they all thanked me.
"Atlas shrugged" by Ayn Rand. Yes, it is long. Yes, some dialogs are way longer than they should. And yes, it is heavy handed. Love it or hate it, it will make you rethink
"Brave new word" by Aldous Huxley. People keep saying we live in a 1984-future, but Huxley's work reflects our present much better than Orwell could ever imagine. Or fear.
"Rendevouz with Rama" by Arthur C. Clarke. Perhaps the first real page-turner i ever read; if the first chapter grabs your attention you'll have a hard time putting this one down.
"A man without a country" by Kurt Vonnegut. A series of essays by Vonnegut which are short, humorous, depressing and thought-provoking all at the same time. Highly recommended.
"Starship troopers" by Robert A. Heinlein. Also heavy-handed and infused with Heinleins' view of politics, but it is very well-written and leaves you pondering after the last page is done. Rico's discussions with his history and philosophy teacher are though-provoking indeed.
"In cold blood" by Truman Capote. Non-fictional account of the Clutter murders on 1959 which is so well written and researched that feels like a novel.
"Foucault's Pendulum" by Umberto Eco. Long and slow in parts, but stylishly definitely one of the best written works i've ever read. The thinking man's version of "The Da Vinci Code".

about 4 months ago
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Enlightenment DR 0.18: Improved Compositing, Wayland Support

Lisandro Re:lol (62 comments)

Pun aside, i had E17 segfaulting a couple times (i've been using me as my DE of choice for over a year now) and it handles crashes surprisingly nice. The screen goes black for a second while the windows manager restarts and you get all your applications back, running as if nothing happened, along a "Sorry, i've crashed" dialog.

about 4 months ago
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The Geekiest Game Ever Made?

Lisandro Darwinia? (87 comments)

Yes, Darwinia, from the same guys who gave us Uplink and DEFCON.

about 4 months ago
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Cassini Gets Amazing Views of Saturn's Hexagon

Lisandro The gif is really amazing (50 comments)

The thought of a planetary-scale standing wave just boggles my mind.

about 5 months ago
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John Carmack Leaves id Software

Lisandro Re:Buying iD was a massive mistake (154 comments)

This guy was the major driving force for the FPS genre and the adoption of GPUs

I think you are giving Carmack too much credit.

Am i? I remember it well. When the first Voodoo cards showed up they were expensive as hell and Quake 2 was the reason to get one. In the span of less than a year after its release most games were supporting either OpenGL or Glide in some way.

Games with excellent gameplay can overcome lack of engineering and graphics, but games with excellent engineering cannot overcome lack of gameplay.

Much agreed. But at least until Q3 no one will argue that iD games were simply fun to play.

Maybe 5 years for now you'll be raving about how good his VR headsets are.

I'm pretty sure that you are wrong, and here are my arguments: ...

Sure, a "software guy" who worked closely with GPU engineers, helped created cutting edge software for the past 15 years, designs and builds rockets and founded one of the most successful indie game companies in history. You don't make it for almost to decades by being "lucky".

I really hate how this makes me sound like a fanboy but the amount of bashing on this thread is increidble. Give credit where credit is due.

you'll be raving about how good his VR headsets are

I'm pretty disturbed by this sentence: do you imply that Carmack will design the VR headsets alone ?

No. Not by a long shot.

about 4 months ago
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John Carmack Leaves id Software

Lisandro Re:Buying iD was a massive mistake (154 comments)

Oh for crap's sake. I know i'm answering to a troll here, but if you don't understand how pivotal was Quake with its "out-of-date" software rendered back in the day then you clearly didn't live the 90s, where the only widespread GPU product out there was the S3 ViRGE. It single-handedly revolutionized the game industry and started a trend to use 3D, without GPUs... which didn't really become popular until Quake 2 showcased what could be achieved with them. 3DFX owes them pretty much all of their business, as everyone else then followed suit, including Romero which had to (yet again) rewrite his glorious Daikatana.

Give credit where due. "Humiliates himself"? This guy was the major driving force for the FPS genre and the adoption of GPUs, and was coding state of the art game engines while you were still picking your nose. Doze off. Maybe 5 years for now you'll be raving about how good his VR headsets are.

about 5 months ago
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Dart 1.0 Released

Lisandro Re:Why not python? (121 comments)

Much, much agreed. I would *love* to see Lua on a browser. It is Python after a marahton diet.

about 5 months ago
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Battlefield 4 DRM Locking Out Part of North America Until EU Release

Lisandro Re:I am one affected (312 comments)

You need to fine-tune your sarcasm detector :)

about 6 months ago

Submissions

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Java 7 ships with severe bug

Lisandro Lisandro writes  |  more than 2 years ago

Lisandro (799651) writes "Lucid Imagination just posted an announcement about a severe bug in the recently released Java 7. Apparently some loops are miscompiled due to errors in the HotSpot compiler optimizator, which causes programs to fail. Apparently this bug impacts several Apache projects directly — Apache Lucene Core and Apache Solr have already raised an warning, noting that the bug might be present in Java 6 as well."
Link to Original Source
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German researchers claim to have found AIDS cure

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Deustche Welle is reporting that Timothy Ray Brown, an AIDS-positive leukemia patient was apparently cured of his HIV infection after receiving a blood stem cell transplant in 2007. The study found that "the patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.""
Link to Original Source
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German doctors claim to have found AIDS cure

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Deustche Welle is reporting that Timothy Ray Brown, an AIDS-positive leukemia patient was apparently cured of his HIV infection after receiving a blood stem cell transplant in 2007. The study found that "the patient remained without viral rebound 20 months after transplantation and discontinuation of antiretroviral therapy.""
Link to Original Source
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Apple press release regarding iPhone 4 reception

Lisandro Lisandro writes  |  more than 3 years ago

Lisandro (799651) writes "Apple has just releases a letter addressing the signal issues a lot of users seem to be having with their iPhone 4. They claim to have discovered the cause for the drop in bars, which is "both simple and surprising" — a wrong formula used to calculate how many bars are displayed for a given signal strength."
Link to Original Source
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Man blames child pornography on his cat

Lisandro Lisandro writes  |  more than 4 years ago

Lisandro writes "A Jensen Beach resdient blamed his collection of over 1,000 images of child pornography on his cat. When confronted by the police, the man argued he used to leave his computer on and his cat downloaded strange material by walking on the keyboard."
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NASA to announce success of Long Galactic Hunt

Lisandro Lisandro writes  |  more than 5 years ago

Lisandro writes "In a cryptic press release, NASA has scheduled a media teleconference on May 14 at 13:00 EDT, to announce the discovery of an object in our Galaxy astronomers have been hunting for more than 50 years. All that was let known prior to the conference is that the finding was made by combining data from NASA's Chandra X-ray Observatory with ground-based observations. Keep in mind that NASA is roughly 50 years old."
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Shutdown day is dawning on us

Lisandro Lisandro writes  |  more than 5 years ago

Lisandro writes "May 3rd this year is Shutdown Day. So called the "one of the biggest global experiments ever to take place on the Internet", Shutdown Day aims to find out how many how many people can go without a computer for one whole day, and to get them to mull over how the increasing use of computers change their lives — for better or for worse."
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Atari founder trashes new games

Lisandro Lisandro writes  |  more than 6 years ago

Lisandro writes "Nolan Bushnell, founder of Atari and the Chuck E. Cheese's Pizza-Time Theaters, stated on a recent interview that he's less than enchanted with modern games, among other interesting tidbits. 'Video games today are a race to the bottom. They are pure, unadulterated trash and I'm sad for that'"

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