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It should be pretty easy to get a high power and supremely noisy transmitter to play havock with this threat to national security.

Might even make the pringles cans go 'POOF'

LCDs have fewer issues with TEMPEST.

The only case where a cast can cause bits of value 1 to be added to a value is when the value starts out negative and it's being lengthened to a larger number of bytes (for example, casting (short)-1 into a (long) will pad with 1 bits rather than 0 bits).

You're thinking of a cast of an integral value to a wider integral type.

That's not what this is - this is converting an integral constant 0 to a null pointer. Such a conversion is not guaranteed to just copy the bits. Nothing in the ANSI C standard says that, for example, on a platform where pointers have a 16-bit segment number and a 32-bit segment offset, and where a null pointer has a segment number of hex FEFE and a segment offset of FFFFFFFF, the expression (void *)0 must result in a pointer with an all-zero segment number and an all-zero segment offset, rather than one with a segment number of FEFE and a segment offset of FFFFFFFF.

Yes, the note in footnote 45 of page 46 of the ANSI C standard, that "The mapping functions for converting a pointer to an integer or an integer to a pointer are intended to be consistent with the addressing structure of the execution environment." would probably recommend that converting arbitrary integral values (which would have to be 48-bit or longer integral values on this platform) just copy the bits - but that's just a note (the standard just says the mapping is "implementation-defined", and if null pointers have to be FEFE:FFFFFFFF on that platform, then (void *)0 has to map to FEFE:FFFFFFFF even if

int i = 0;
char *p = i;

would result in p being 0000:00000000. Yes, this is a bit counter-intuitive, but, given that C didn't have the notion of "nil" or some other null pointer constant from Day One, that's life.

See question 5.5 in the comp.lang.c FAQ (and the rest of section 5 of that FAQ, devoted to the null pointer) for more details.

As people said above, the language definition dictates that 0 == NULL. Mod parent idiot.

That's relatively recent. See here for examples of where that wasn't true

This is doubly ironic, because the C standard does not guarantee that if (!ptr) has the same result as (ptr != NULL). NULL does not have to be "zero" and on some strange CPUs, it actually is not zero.

if (!ptr)

if (ptr != 0)

So to be correct, one should never test vs. 0, but rather vs. NULL.

No, "implementation defined" means that it is up to the compiler, OS (if present), and possibly the hardware to determine what will be used to represent the NULL address.

This is addressed in the C-FAQ where systems from Prime, Data General, and Honeywell-Bull are noted for having non-zero null pointers (at least for their C-compilers).

This issue brings up one of my pet peeves with C++. The designers (I don't think Stroustroup deserves all the blame)went all out in adding weak type safety to the language by eliminating automatic casts but then they determined that "((void)(*0))" violated they safety model and decided to invoke special "spooky" behavior when comparing pointers against the literal zero. This of course leads to the annoying practice of leaving out the Boolean operator altogether and using "if(foo)" and "if(!foo)".

I imagine the C++ architects were at least partially motivated by their "macros are evil" mantra (why they didn't do anything about the need for header guard macros is beyond me). They should have had the guts to introduce a new "null" keyword. This would not conflict with existing ANSI C code using NULL and code could easily be ported with substitution or:

#define NULL null

Ummmm... Wrong! Go read your ANSI C standard. NULL == 0 == false by definition. See C FAQ, Q5.2

the argument against it that I know is that NULL is not nec cast to false, and NEITHER have to be (int)0

1. There's no such thing as "false" in C. !x is equivalent to x == 0. See the comp.lang.c FAQ item about this.
2. I'm not sure what you mean by "be (int)0", but note that, regardless of how a null pointer is represented in a particular C implementation, comparing a pointer against 0 is interpreted as comparing it against a "null pointer constant"; see the comp.lang.c FAQ item about this.

Here's all the items about null pointers in the comp.lang.c FAQ.

the argument against it that I know is that NULL is not nec cast to false, and NEITHER have to be (int)0

1. There's no such thing as "false" in C. !x is equivalent to x == 0. See the comp.lang.c FAQ item about this.
2. I'm not sure what you mean by "be (int)0", but note that, regardless of how a null pointer is represented in a particular C implementation, comparing a pointer against 0 is interpreted as comparing it against a "null pointer constant"; see the comp.lang.c FAQ item about this.

Here's all the items about null pointers in the comp.lang.c FAQ.

the argument against it that I know is that NULL is not nec cast to false, and NEITHER have to be (int)0

1. There's no such thing as "false" in C. !x is equivalent to x == 0. See the comp.lang.c FAQ item about this.
2. I'm not sure what you mean by "be (int)0", but note that, regardless of how a null pointer is represented in a particular C implementation, comparing a pointer against 0 is interpreted as comparing it against a "null pointer constant"; see the comp.lang.c FAQ item about this.

Here's all the items about null pointers in the comp.lang.c FAQ.

Althoug the comparision (0 == ptr) might for some twisted reason com out as a non-zero value, you are not guaranteed that (!ptr) will have the same value.

Wrong

Don't give advice... ah, screw it. You get the idea.

As a matter of style, many programmers prefer not to have unadorned 0's scattered through their programs. Therefore, the preprocessor macro NULL is #defined (by or ) with the value 0, possibly cast to (void *). [emphasis mine]

Wrong. NULL is guaranteed to be 0 on all platforms. The binary representation might differ so memset(&ptr, 0, sizeof(ptr)); won't work where (void*)0 isn't represented by all binary zeros but (NULL == 0) will always be 1. See the C FAQ

Wrong. Here is a good explanation in lay terms. You can find much more detailed explanations with a bit of digging.

RE: LASERS EMIT COHERENT LIGHT, BUT NOT BECAUSE THE ATOMS EMIT IN-PHASE LIGHT WAVES

I ran across your site, and I would like to point out that your explanation for the coherence of laser light is incorrect. Coherence and phase are intrinsically-related. Measurements of the temporal or spatial coherence of light are in fact measurements of the relative phase of two different samples of a light wave. The fact that stimulated-emission results in an emitted photon that is exactly in-phase with the incident photon does explain spatial coherence. This is because the laser beam originates as a single (or relatively few) spontaneously-emitted photon(s). That photon is amplified by the stimulated-emission process to form the laser beam. Because the path of the initial photon is generally not along the optical axis of the laser cavity, and because it can be coherently scattered as it propagates through the gain medium, it traverses the gain medium along many paths. Thus the entire laser beam inherits its phase from the initial spontaneously-emitted photon, and is therefore fully spatially-coherent. Even if we consider the laser beam to originate from several spontaneously-emitted photons, the result is that beam is the superposition of several fully spatially-coherent beams, which can be shown to be a fully spatially-coherent beam.

You are correct that starlight becomes more spatially-coherent by propagating long distances, but that cannot the mechanism for the spatial-coherence of a laser, as I will explain with a fairly simple counter-example. With Q-switching, it is trivial to switch a laser on and off within 10 nanoseconds, in which time light travels about 3 meters in vacuum. Yet the laser pulse can be measured to be as or more coherent than starlight, even though its propagation distance is on the order of meters rather than light years.

You are correct that the pure color (monochromaticity) of laser light is due to the mirrors (which form a Fabry-Perot or some other resonant cavity), but I would argue that the explanation for the pure color for laser light is at a less advanced level (third-year physics undergraduate) than the explation for its coherence. Coherence is an advanced-undergraduate to graduate-level topic, as a proper analysis of coherence requires Fourier transforms, and the coherence of stimulated emission is a topic in quantum electrodynamics. The most readable but rigorous treatment of optical coherence that I am aware of is _Statistical Optics_ by Joseph Goodman, but even that is written at the advanced-undergraduate to graduate level.

This is true, but does not explain the mass coherence of laser light. It cannot explain why only a single phase becomes prevalent. Remember the principle of superposition -- if laser action depended solely on the in-phase emission of radiation, that would not preclude the simultaneous existence of a great number of different phases. The number of phases would only be limited by the number of radiators available in the lasing medium.

It is, in fact, the mirrors which cause the light to become coherent en masse as opposed to being a mixture of phases. This is for the same reason that starlight is coherent, even though it was not so when it was emitted -- it has travelled a very large distance.

As I've already posted below, this is a fairly good explanation in simple terms.

The idea that laser light is coherent because of the in-phase emission of radiation is a misconception which has unfortunately been so widely disseminated that even some physicists believe it. It is a symptom of an education system based on rote memorization instead of critical thinking.

Wrong. Here is a good explanation in lay terms. You can find much more detailed explanations with a bit of digging.

Yes, that's the trick that some seem to be missing here when they talk about computing hash values faster than you suggest. You gotta read the whole file to compute a hash UNLESS you've only changed the last part of the file, in which case you could take the cumulative result and work from that point. If someone can show that the SHA-1 shortcuts the researchers found allow you to change data specifically at the end of the file, please correct me. Until then I'll assume that any assertions to the contrary are merely wild speculation.

Here are some real numbers for computing various hash values using Crypto++ 5.2.1. Even on a 1.6 GHz Opteron, SHA-1 hashes are computed at a rate of 100 MB/sec. Even a truckload of Opterons won't finish the job any time soon.

example)

But the question is, can interlingua successfully translate between AOL speak and 'leet speak? We're talking about chatrooms here, you know.

I also found calls to Cybergold, Cydoor and the like.

Wouldn't it be nice to carry around a specialized laptop that could act as both a portable display and input device? Does something like this currently exist?

Ah, but it does. Serial Terminal Linux is an ultra minimalist floppy distro that boots up as a serial terminal. You don't have to install a thing, and it will give you easy connectivity because it automatically boots into minicom on one virtual console per serial port.

And then you boot your lappy with this http://www.eskimo.com/~johnnyb/computers/stl/. If you need physical access, and the boxes are not Winders, might as well serial.

"We should forget about small efficiencies, say about 97% of the time:
premature optimization is the root of all evil." - Donald Knuth
"Programming can be fun, so can cryptography; however
they should not be combined." - Kreitzberg and Shneiderman
"More computing sins are committed in the name
of efficiency (without necessarily achieving it)
than for any other single reason - including
blind stupidity." - W.A. Wulf

"processors are never so fast or memory so big that the next generation of customers can't be convinced to buy software that strains the system"

A typical laser will have a beam spread of 1.5 mRad.
As a rule of thumb this is about 1.5 millimeters spread to each meter

This or this might help with the "WTF".

No - according to the C and C++ standards, main must return an int.
See the C FAQ

Why bother with the acoustics when you could monitor the EM radiation and pick it up farther away ( TEMPEST-style)?

LOL, It was that or fail 3rd grade.

I chose to take a risk and I went from failing math to the 99th percentile in most subjects. I also read over 200 books and learned to program in 5 years, hell by the time I was back I could have taken the GED and skipped HS. I mean sorry if taking a student that was failing most subjects to the top of his class in 5 years is not enough for you.

O and by the way while I almost failed English I was taking HONERS English at the time. And I still got out of HS and though college hell I passed the AP English test and got a 700 English 710 math on the SAT's my English hit 800 on the PSAT... But hey I should have sat back in public school and retaken the 3rd grade. Because as we all know knowing when to use who vs. whom is the secret to success in life.

PS: Check out http://www.eskimo.com/~miyaguch/sat.html to see how high those scores really are.

I thought that was defined as the default left to right order, of course i could be wrong.

Yes, I'm afraid that's it. Look up the definition of 'sequence point' in e.g. the comp.lang.c faq that's got a very good explanation of this. IMHO the whole comp.lang.c. faq is a must read for any 'C' programmer. Trust me, time spent going through it is well spent.

Yeah, that P2P sure doesn't run on Mac! Between those, you can connect _really well_ to limewire networks (Next time you are on a Mac, try Acquisition. It's an absolute dream), just fine to .torrents, and perfectly well to eDonkey, OpenNap and Kazaa networks. Boy, I sure wish I could use P2P on my Mac. Yeah, I never download anything...

Would encryption be of any use? I'm not familar with the "Tempest project" thing mentioned above.

More information on TEMPEST than you'd probably want to know.

And no chance of winning, so he's not really a choice, even if he's on the ballot.

The presidency is not a horse race. The winner is not a foregone conclusion with voters "placing bets". Your vote decides the outcome. If you and your friends and their friends vote for Badnarik, then he will win, just as assuredly as Kerry would win if you vote for him or Bush if you vote for him. If you don't vote for what you believe, you'll never get what you want. It's not as if Bush/Kerry is going to pay more attention to what you say since you voted for him - he'll just be laughing all the way to the White House.

PS You want Condorcet, not IRV.

I flew Search and Rescue missions for WASAR for a few years. It's usually very difficult to locate a downed plane based only on the 121.5MHz ELT. How ironic they managed to locate this guys TV...

Oh please for the love of Pete, NO! I've said this many times on \. already too, but this is LJ post is the only recent one I can find. IRV is a provably flawed system, please stop advocating it! Pushing for voting reform is great, but we need Condorcet voting, not IRV.

And BTW, we need to keep the EC.

OH, yea - and an AMAZINGLY broad platform base..

From:Xastir Features List

TWENTY-ONE+ SUPPORTED OPERATING SYSTEMS/VARIANTS
1) FreeBSD
2) Mac OS X
3) Linux: Caldera, Debian, Lindows, Mandrake, RedHat, Slackware, SuSE...
4) Solaris: 2.5, 2.6, 7.0, 8.0
5) Windows + Cygwin: Win95, Win95b, Win98, Win98se, WinME, WinNT4, Win2000, WinXP.

Then there's the seven languages and over 124 map formats....

Uh, how many of you drive cars with a cell phone turned on? With the location based services the phone companies have, it is easy to triangulate your position, speed, and heading. Overlay a map and they know where you are. Another reason to turn off that phone and drive. I think I should build a new car, and call it the TEMPEST. Either stop emitting all of your electronic signatures, or live your life like an open book.

Condorcet's method avoids Duverger's Law by providing a ranked voting system in which all preferences are simultaneously pairwise evaluated. It can be seen as a generalization of plurality voting and approval voting. However it is unlike Instant Runoff Voting, which also uses ranking and pairwise comparisons, because IRV evaluates preferences sequentially, discarding some as it goes. So though the vote casting method is the same between the two, the vote counting method is different.*

To get a conceptual grasp for what Condorcet tries to do, ask yourself what the definition of "election winner" is. Plurality voting says it is the guy with the most votes. This has a strategic problem whenever there are more than two candidates, however - are you really voting for candidate A, or against candidate B when you really prefer dark horse C? Since the system doesn't allow you to express your full preferences, there is a temptation to abandon your principles and put your vote where you think it will have the most effect - behind one of the two perceived front-runners. They're perceived that way because everyone else faces the same dilemma you do.

OTOH, Condorcet voting says the winner is the candidate who would win a clear majority of head-to-head elections against all the other candidates individually. If you're the best candidate, then this is something you ought to be able to do - right? When clear 1-2-3 preferences are given, it is easy to tally this. Time-consuming (you're not counting ballots but "wins" - so in an n-way race there will be (n^2 - n)/2 "wins" on every ballot) but conceptually easy.

Note this is related to how the media looks at 3rd parties as "spoilers" - they ask people "if Nader wasn't in the race, would you vote Bush or Gore?" Why don't they ask "if Gore weren't in the race, would you vote Bush or Nader?" Maybe Gore was a spoiler for Nader! If you can vote for who you really want (Nader, for example) while still making your preference of Gore over Bush clear, the spoiler problem is eliminated. With Condorcet, you can vote your conscience without sacrificing the result!

The Condorcet winner tends to be the concensus winner - he might not be the first choice of the largest voting bloc, but the average voter satisfaction will be higher. Take the 1912 presidential race. Together Roosevelt and Taft got 51% of the vote, and differed little. But Democrat Wilson won with only 42% because the other two split the conservative vote. I think it's fairly obvious that the 51% would have been happier had either Roosevelt or Taft won, though only about 25% would have listed either as their first choice.

I like to think of the Libertarians as the parallel today. Fiscally conservative and socially liberal (to generalize), they can be seen as "between" the Democrats and Republicans. Though they might not win many first-place rankings, I tend to believe that most Ds and Rs would prefer them over the "other guy". This large number of second-over-third-place wins could put them over the top. And conceptually this makes sense - you get a president that a clear majority can live with, instead of a polarizing factor in the Oval Office.

FWIW, approval voting comes somewhere between these models. You can give multiple candidates a "thumbs up" instead of just one like plurality, and the guy with the most votes still wins, but there is no differentiation between them like Condorcet. Thus there is still a temptation to vote strategically. If you approve of A and B but actually preferred A, you might not give an approval to B in order to sabotage his chances. Then we're right back to plurality voting and two major candidates.

*Sidebar: IRV is dangerous beca

For those wishing to find organizations more stringent in their requirements than Mensa (pages all from :

TOPS (99th percentile, which apparently equates to a 1360 on the SAT, which is surprisingly low)
One in a thousand society (99.9th, ~1520 on the SAT), all the way to the Giga society which demands with a straight face an IQ of 196 or higher to join.

Ok, I'm tired of providing links. Look a few pagefuls down on this page http://www.eskimo.com/~miyaguch/hoeflin.html and you'll see that such societies are both in abundance and have widely varying selection criteria. I qualify for most - but certainly not all! - of those societies purely on academic test scores (haven't been IQ tested since I was a youth) but don't see the point of them and don't feel like going through the trouble of specialized "entrance exams". I can stroke my ego myself, thank you very much, and defining any of my life strictly on "how smart I am" vs. "what I have accomplished" or "what am I in the process of accomplishing" would be counterproductive imo.

For those wishing to find organizations more stringent in their requirements than Mensa (pages all from :

TOPS (99th percentile, which apparently equates to a 1360 on the SAT, which is surprisingly low)
One in a thousand society (99.9th, ~1520 on the SAT), all the way to the Giga society which demands with a straight face an IQ of 196 or higher to join.

Ok, I'm tired of providing links. Look a few pagefuls down on this page http://www.eskimo.com/~miyaguch/hoeflin.html and you'll see that such societies are both in abundance and have widely varying selection criteria. I qualify for most - but certainly not all! - of those societies purely on academic test scores (haven't been IQ tested since I was a youth) but don't see the point of them and don't feel like going through the trouble of specialized "entrance exams". I can stroke my ego myself, thank you very much, and defining any of my life strictly on "how smart I am" vs. "what I have accomplished" or "what am I in the process of accomplishing" would be counterproductive imo.

For those wishing to find organizations more stringent in their requirements than Mensa (pages all from :

TOPS (99th percentile, which apparently equates to a 1360 on the SAT, which is surprisingly low)
One in a thousand society (99.9th, ~1520 on the SAT), all the way to the Giga society which demands with a straight face an IQ of 196 or higher to join.

Ok, I'm tired of providing links. Look a few pagefuls down on this page http://www.eskimo.com/~miyaguch/hoeflin.html and you'll see that such societies are both in abundance and have widely varying selection criteria. I qualify for most - but certainly not all! - of those societies purely on academic test scores (haven't been IQ tested since I was a youth) but don't see the point of them and don't feel like going through the trouble of specialized "entrance exams". I can stroke my ego myself, thank you very much, and defining any of my life strictly on "how smart I am" vs. "what I have accomplished" or "what am I in the process of accomplishing" would be counterproductive imo.

Maybe Sony is using Fogal transistors on the input circuit. That wey they can access the complete scene information enfoldedalated in the noisy signal. Or sumthin'.

The US has a two-party system because plurality voting leads to Duverger's Law. Essentially, a single choice can only decide between two things (duh). When you introduce a third (or more) then there are multiple preferences, and these are not recorded by the system. These secondary preferences, when taken en masse, could have influence. This is the basis for Condorcet's method of voting. But since everyone somehow "knows" that only the top two contenders matter (though this becomes a self-fulfilling prophecy as we preselect the two that matter), and the only way to get what you want is to hold your nose and vote for something you don't want (now there's logic for ya!), this is what we're stuck with. If everybody simply voted honestly for their conscience/principles, we'd be better off. But most people vote out of fear instead.

"Independent" or "third party" candidates also appoint electors should their party's candidate win. For example, I am an elector for my party here in Nebraska.

Though I no longer use them, I was very happy with Eskimo.com. They give discounts if you're only using ssh/telnet to access the shell account, and they have great support. They use Linux and SunOS, though their news server, when I was last there, crashed a lot.

Check out their home page, but I do believe you get full IMAP access as well as compiler access. I remember compiling my own version of Pine as they were a version behind, and all worked just fine.

They're not free, but I think you'll find their rates ok. /vjl/

[tinfoil hat on] And so they want to be only ones with enough juice power to break ciphers/ do research in that area...
But the programmers don't need anything over P3 rihgt? Can play games, can send email, can do sound processing... Can cluster... can send attachments and spam...
On the other hand, some free research arround:
this is being optimized for P4 (open sourced, good good).
this can do 35 million md hashes in a second on a pentium 4.(not quite 35, but read the page)
this breaks des and the approximate time for P4 is 4.3 hours (not quite 4.3 but read the page)
I just wonder, if the hardware industry splits, how much the software world will diverge. Of course, other countries don't have the jump US has in this area, but given enough time, the demand will drive the market....

"debian" - only 1 result
"gentoo" - full page of results but cannot go to the second page no matter how many times I hit next, on the 4 hitting NEXT it returns "no results found", WTF???
"redhat" - full page everything ok
"linux vs windows" - some times full screen of data, some time hitting search returns "no results found", this is interesting
"ms office" - only one link
"microsoft office" - full page of links
"linux is better than windows" - full page, ok
"is linux better than windows" - full page , ok

Comparative tests
"Sorry, no results were found containing "windows sucks" - google returns half a million pages on the same query, conclusion #1, microsoft disagrees, they don't sux.
BTW I found this rant on why windows sux :), also found this funny page, be sure to check it out :) from the authors:
"Why microsoft shouldn't own a fast food company. At mc donalds they ask 'would you like fries with that'. At the microsoft fast food chain they ask, 'Do you want any more bugs with that'"

After 25 tries of "cannot process your query", I got : "Sorry, no results were found containing "windows is bad", fishy.
And of course, the entry 'longhorn' returns and entry titled "Longhorn from India, Longhorn for the .NET developer" :)) Now we know.

"Making money is a beautiful thing...unless you're doing it through patently illegal activities."

Also unless you are exploiting others in a legal way. The "invisible hand" of Adam Smith does not mean that businesses should not care about others, but that they don't have to keep the global economic picture in mind when making decisions. The obligation to responsibility, ethics, and morality is still there.

On another note, while I am pro-business, I am anti-corporation. I wrote a short essay about it here. Basically, with corporations, the owners have neither control nor responsibility, but the people who do have control only have a responsibility to the shareholders. However, the only way they can communicate is through stock price. This makes those in control only answerable to the stock price, and not answerable to ethical obligations that the shareholders may themselves believe in.

I predicted this two years ago (see prediction #2 - the rest weren't so accurate).

Here and here and here and here.

Especially this one -- states that they finally got a model that doesn't use a fudge factor, but it doesn't predict as much global warming, either.

Google is your friend. The above links all came off the first page of searching for ""climate models" "fudge factor".

Check out My article on the subject. Basically it talks about the problems of corporations as apposed to sole proprietorships.