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January 15

Copyright and Snowden

Why was Snowden charged with "theft of government property"? I understand why he was accused of being a spy, but isn't any document produced by the government automatically in the public domain, even if not on the internet? Unless he indeed stole some computer, I don't get why the theft charge. --Scicurious (talk) 14:42, 15 January 2016 (UTC)

Public domain relates to copyright only. Despite what all those ads from the MPAA etc say, people aren't charged with theft over copyright issues. Nil Einne (talk) 15:12, 15 January 2016 (UTC)

Yes, copyright infringement does not lead to a theft charge, it leads to a copyright infringement charge, besides civil penalties.--Scicurious (talk) 15:31, 15 January 2016 (UTC)

Yes, so the point is public domain is likely irrelevant. There's no suggestion copyright is involved, plenty of reasons to think it isn't. Nil Einne (talk) 16:40, 15 January 2016 (UTC)

I'm not sure anyone knows. Aside from the mere list of charges, I think the details of the allegations are still sealed. It could be alleged that he took a hard drive, or physical papers, or just about any object really. Dragons flight (talk) 15:19, 15 January 2016 (UTC)

Yeah was going to say the same thing. I did a search, and while I found one or two searches criticising the charge like [1], the best comment I could find was by a commentator here [2] left at June 23, 2013 at 3:39 pm which says something similar to Dragons flight. We don't know precisely how the government claims to have established the elements for the theft charge because they haven't publicly revealed it. From what I can tell, this hasn't changed, and probably won't change until Snowden either returns to the US to face the charges, or perhaps if the government drops them for some reason. Nil Einne (talk) 15:27, 15 January 2016 (UTC)

It seems then, that's all the non-speculative information we can get. Scicurious (talk) 15:31, 15 January 2016 (UTC)

I did find [3] from 2014 which seems to confirm that at the time the case remained sealed. (N.B. I'm not endorsing other aspects of that source.) I'm fairly sure it must remain sealed now, otherwise I would have found something new. Besides the possibilities I mention above, if an extradiction proceeding ever gets under way and is challenged by Snowden, it's likely some details would have to be revealed to the foreign court. This doesn't guarantee it will be made public, but in a number of countries it may be difficult to prevent an outline being made public unless there's a very good reason. Consider the Megaupload legal case for example. Nil Einne (talk) 15:51, 15 January 2016 (UTC)

Mr. Snowden was charged with theft of government property because attorneys for the United States Government believe he stole government property. In this statement, the Justice Department outlines its charges, which were made in a criminal complaint to the federal court in the Eastern District of Virginia. Among the complaints were charges that Mr. Snowden committed unlawful acts as defined in 18 U.S.C. § 641. There are lots of ways to violate the law, and it is not yet clear which laws - if any - were violated; this is why the case must be tried.

Have a look at §641. One could commit unlawful acts by embezzling, purloining, stealing, "knowingly converting," ... receiving, concealing, or retaining, ... property of the United States. All the attorneys must do is prove that the defendant did any of those things, and they can convict him of a federal crime that may carry a prison term.

Nimur (talk) 16:11, 15 January 2016 (UTC)

"...because attorneys for the United States Government maintain he stole government property". We don't know what they believe, and in this particular case, my good faith does not extend very far any more (it took a first big hit when, shamefully, moral failure John Yoo drafted and despicable human rights violator Jay S. Bybee signed the Torture Memos without causing the mass armed uprising we are promised when the government violates basic freedoms). --Stephan Schulz (talk) 16:39, 15 January 2016 (UTC)

Persons accused of espionage have always also been charged with theft of government property, the classified information, since the Daniel Ellsberg case was dismissed. Ellsberg's defense was that the Pentagon Papers should not have been classified. The US espionage act does not refer explicitly to classified information, but contains a long list that is essentially a classification guide, identifying types of information that should be classified. Ellsberg argued that, since the Pentagon Papers should not have been classified, he was not committing espionage. (Don't attempt this defense in the United Kingdom.) In order to deal with defenses of this sort, since the dismissal of the charges against Ellsberg, the accused spy has always also been charged with theft (of the documents). (By the way, the charges against Ellsberg were dismissed, not because of the issue of whether the papers should have been classified, which never came to trial, but because of misconduct by the prosecution at the instructions of the Nixon Administration.) That is why he was also charged with theft. Robert McClenon (talk) 18:05, 15 January 2016 (UTC)

Online Money

How to earn money by creating a website and where does the money gets deposited? Also what are the other ways to earn money online? — Preceding unsigned comment added by 59.88.196.26 (talk) 17:40, 15 January 2016 (UTC)

You can earn money as a web developer - that is creating a website. The money will be deposited wherever you want it to be deposited. There is no such thing as web pages that magically create money and hide it in a magical pot at the end of a rainbow somewhere. You will need to do some work. As for other ways of earning money online - just get an online job and do some work. If you are looking to make money without working, there are millions of people looking to make money without working. There isn't much free money to go around, so you need to do a hell of a lot of work to make avoiding work profitable. 199.15.144.250 (talk) 17:54, 15 January 2016 (UTC)

You could (possibly) create a website with enough useful content that a lot of people would want to visit it...then you could go to a company like Google and have them pay you to place advertising on the website. However, you need a HUGE number of visitors (tens of thousands per month) to earn even a tiny amount of money that way. I believe Google will direct-deposit money into your bank, or mail you a check once they owe you more than $100 - or monthly if you're earning more than $100/month. However, if you think this is going to earn you a ton of money - you're severely mistaken. That'll only happen if your content "goes viral" and is viewed by millions of people.

You could also use a website to serve as a 'storefront' for some other business (involving products, sales, services - actual work of one kind or another) - in which you could have people deposit money via PayPal or something similar.

But there is nothing magical about making money on the internet...it's not that the internet generates the money for you...you USE the internet to get money from whatever work you put into it. There's no such thing as a free lunch. SteveBaker (talk) 18:23, 16 January 2016 (UTC)

Nonprofit confidence trick

I have a website that I haven't worked on for years (alternativegiving.org), and most of the mails I get for it nowadays is spam. Now I just got a type of mail I have not seen before:

We need not mention the obvious signs that point to a confidence trick. I removed the name (which did not yield any pertinent information) because there is an off chance that it's just a very selfless person who also is clueless. (I'm following my own variant of AGF here, which is why I'm taking your and my time with this message.)

I would like to help protect others, especially since this is targeting nonprofits, for which, as a contributor to wikipedia.org, I obviously have a heart. Should I report this? If so, where? There is http://www.stopfraud.gov/report.html, which says "Fraudulent activities should always be reported to your local law enforcement office.", but I don't want to bother my local police with something like this. The same site also refers to https://www.ic3.gov/default.aspx, but that's only for when you have become a victim. http://www.ripoffreport.com/ seems to be only for consumers. I once reported some suspicious activity on some other site, I forget which, but I never learned what became of it. — Sebastian 17:53, 15 January 2016 (UTC)

It is a waste of time to report it. The only organization that actually tries to help in these cases is the Better Business Bureau. They are very picky on what they do with online businesses. They online company must be owned and operated in the United States, or all they will do is file your complaint away and ignore it. 199.15.144.250 (talk) 17:58, 15 January 2016 (UTC)

Thank you; there's no indication that there is a company behind it, nor that the sender even is in the US. — Sebastian 18:04, 15 January 2016 (UTC)

I wouldn't reply to any such e-mails unless they tell you which organisations they have helped (so that you can find out how much they "helped"). There are many fraudsters who wish to get their hands on genuine websites to add malware. Dbfirs 09:32, 16 January 2016 (UTC)

That is what your junk folder is for but you can use an organization like Spamhaus so others have aren't bothered with the rubbish. Anyone actually doing stuff like that anyway well will be plied with quite enough work in their local area. Dmcq (talk) 14:29, 16 January 2016 (UTC)

In many cases, these people just generate a stock webpage from some automated tool. The webpage itself may be free - but I guarantee there are other charges for "maintenance" or search-engine-optimisation or some such junk. Just ignore them. SteveBaker (talk) 18:06, 16 January 2016 (UTC)

The reason why I posted this was not to ask whether I should reply, or where to move spam, nor to speculate what the senders might do (although that's interesting; what Steve suggested is actually marginally honorable; an option which hadn't occurred to me). No, I posted this here because I believed it's most likely a confidence trick targeting nonprofits, and I want to help protect others and warn them. — Sebastian 20:41, 17 January 2016 (UTC)

@SebastianHelm: Here are a few other places you could report it [4], I would try at antiphishing.org, their aim is mostly to get the word out. You could also try forwarding to nonprofit consortiums and resource centers on social media or listservs. If you google /nonprofit [resource, consortium] [your location]/ you should find a few people who would appreciate the note. SemanticMantis (talk) 17:53, 18 January 2016 (UTC)

Thank you, SemanticMantis, that's exactly what I was fishing for! — Sebastian 19:16, 18 January 2016 (UTC)

January 16

Software

When a courier guy delivers the package, he asks me to sign on his phone. And automatically this gets updated on their website : as package delivered. What is the software they use? — Preceding unsigned comment added by Stalson92 (talk • contribs) 02:28, 16 January 2016 (UTC)

@Stalson92: Since you haven't told us which courier company you're thinking of, I don't see how we could definitively answer this question. There are thousands of courier companies in the world. Perhaps the best course of action for you would be to just call the courier company and ask them. You may need to speak to a supervisor or manager but someone there should know the name of the software. Dismas|^(talk) 14:39, 16 January 2016 (UTC)

FedEx — Preceding unsigned comment added by 103.60.68.122 (talk • contribs) Stalson92 (talk) 15:40, 16 January 2016 (UTC)

Usually, those companies are large enough to develop their own software. It may have an internal name - but I doubt that'll help you much. SteveBaker (talk) 18:04, 16 January 2016 (UTC)

Even with the OPs clarification on company, they still didn't mention a location (geolocation gives India).

I wonder whether FedEx always use the same software anyway or just need it to be able to communicate with their servers via their standard API. While I've only ever received one package from FedEx here in NZ, their system seemed to be similar to what many courier companies here use now (and have been for a few years). I didn't sign on a phone but some specialised terminal.

In some countries and places (including I believe some places here in NZ), FedEx do not have their own drivers but instead rely on deals with other courier companies. It's possible they still require the use of specialised FedEx devices, but it would seem more likely they're fine with these drivers using their own devices which either communicte with FedEx via their API or communicate with the drivers courier company which then connects to FedEx.

I guess the phone thing is useful for temporary drivers and similar and perhaps also where the only want to provide one device (particularly in the developing world where they need to keep costs down and can't assume everyone will have a phone for contact). But even then, I wonder if there are circumstances where they don't use the same software.

And we can't even be sure that the software is universally used, e.g. if it's in English perhaps the Chinese or whatever division found it easier to develop their own software (if they have any) rather than translate it. Particularly if other features don't work well in China (or wherever) for whatever reason.

I suspect the phones the OP referred to were Android; while porting Android apps to Windows is often not that hard (as I understand it), again it may be that someone would find it easier to start from scratch. Windows isn't really that popular anywhere, but if the company is providing the phones it's always possible they could choose Windows ones for whatever reason.

Nil Einne (talk) 12:07, 18 January 2016 (UTC)

Pseudocode mod of a negative integer

In pseudocode, is the mod of a negative number >= 0 (as in mathematics)? In some languages, -7 mod 5 returns -2 instead of +3. Bubba73 ^{You talkin' to me?} 02:35, 16 January 2016 (UTC)

Pseudocode isn't well enough standardized for this question to have a standard answer. As with any other mathematical notation, the author should clarify the meaning where it's ambiguous. Standard mathematical notation has no mod operator. One normally writes x ≡ y (mod p), not, e.g., (x mod p) = (y mod p). -- BenRG (talk) 02:44, 16 January 2016 (UTC)

The book has an appendix about its pseudocode, but it doesn't say. I'm going to assume that the result is non-negative, because a negative value doesn't seem to do any good. Bubba73 ^{You talkin' to me?} 02:57, 16 January 2016 (UTC)

Resolved

Real programmers rarely (if ever) use pseudocode - and then only where there is a gun being held to their heads. It's one of those things like flow charts and UML diagrams that academics fondly imagine should be a good idea and spend endless time getting excited about. In practice, experienced people can read real code (in their preferred language) much more easily than pseudocode - so we just write things in real code to start with and save an unnecessary step. In practical situations, it's almost always the case that the pseudocode contains bugs that aren't noticed until the real implementation is working (because there is no way to compile and test the pseudocode) - and then nobody goes back to fix the pseudocode and it's immediately rendered worse than useless.

That said...

In the unlikely event that you're trying to describe an algorithm in pseudocode without specifying an implementation language - then you'd need to be super-careful about things like that. IMHO, if you need to be portable and you are planning to take the MOD of a negative number - then you should explicitly test for a negative input, and in that case calculate mod(-x) and handle the result accordingly. This makes the process entirely explicit and whoever is given the thankless task of converting pseudocode into real code can choose to optimise this (or not) depending on what their underlying language supports. Either way, a bloody great comment describing what is intended and why - and warning of the anticipated portability issues - is absolutely required here! SteveBaker (talk) 18:01, 16 January 2016 (UTC)

Pseudocode is common in computer science papers. It is usually block-structured like popular programming languages, though you do sometimes see flowcharts. It is useful in the same way as other mathematical notation. It is generally easier to understand an algorithm from a pseudocode description than from a plain-English description or an executable implementation. -- BenRG (talk) 20:33, 16 January 2016 (UTC)

I was trying to translate some pseudocode in a book to a working program. (I found what I think is a typo, but fixing that and making the result of modulo >= 0 and it works.) Speaking of flowcharts, I used them routinely in real programming when I used non-structured languages (e.g. spaghetti Fortran, Basic, and a little Cobol). But when I went to structured languages in 1981, flowcharts no longer applied. Bubba73 ^{You talkin' to me?} 21:29, 16 January 2016 (UTC)

I am a real programmer and, contrary to Steve's experience, I have often found pseudocode a useful tool when drafting the basic algorithm for a procedure. I find it very convenient to write something like

    while any moles are visible {
       find nearest mole to hammer
       move hammer over mole
       whack it
    }

and then translate that into real code. A real-life example would be more complicated than that one, but still no more than around 10-15 lines of pseudocode. --76.69.45.64 (talk) 07:43, 17 January 2016 (UTC)

I agree. Bubba73 ^{You talkin' to me?} 23:06, 17 January 2016 (UTC)

Agreed as well. Though in my case, I use it more like a note that I need to come back to write code there, because I'm already in the middle of writing something else. --Wirbelwind(ヴィルヴェルヴィント) 19:01, 20 January 2016 (UTC)

GIMP 2 and animated GIFs

Passive permit traffic signaling in Göttingen, Germany

pictures from camera

I need help understanding some options for saving animated GIFs. In File + Export, with GIF selected as the output type, there are the following options dealing with animation:

Delay between frames where unspecified: ____.

□ Use delay entered above for all frames.

So, does this mean checking the box overrides the "where unspecified" part above ? If not, what does it do ? And is there a way to see which frames have their own delays specified and change them individually ? StuRat (talk) 03:27, 16 January 2016 (UTC)

GIMP converts the layers of the picture to an animated GIF picture. The delay is framerate of the flip book.[5] Use delay entered above for all frames. is a constant flip rate of the layers. GIF is compressed file format. If there's no change for longer, the best compression is not to flip the fame picture, it is more easy to choose an extra delay time till flipping the next frame. --Hans Haase (有问题吗) 12:03, 16 January 2016 (UTC)

I have only used GIMP occasionally, but here's what I remember. When opening or saving GIF files, each GIMP layer is considered a GIF frame. The frame duration is specified in the layer name in parentheses: GIMP Tutorials - Simple Animations shows examples like (1000ms) and (1500ms). Based on that, I intepret the options above to mean:

• If the layer name doesn't specify a duration in parentheses, use this default duration: ____ milliseconds.
• □ Ignore durations specified in the layer names and always use the default duration above.

You can probably do a test to confirm that's how they behave. --Bavi H (talk) 19:31, 16 January 2016 (UTC)

Thanks for the info ! StuRat (talk) 22:04, 18 January 2016 (UTC)

Futuristic font(s)

I'm searching for a 'list' of futuristic fonts for MS Office/Word. Something that actually 'looks' futuristic not just 'entiles' futuristic. What do you guys recommend? -- Mr. Zoot Cig Bunner (talk) 20:00, 16 January 2016 (UTC)

Just try a Google image search for 'futuristic fonts.'--3dcaddy (talk) 20:48, 16 January 2016 (UTC)

Greetings Russell.mo, At website www.dafont.com search for cyber fonts will give a good selection. Regards,  JoeHebda (talk)  17:14, 17 January 2016 (UTC)

Anyway,

3dcaddy: Checked before posting!... Thank you.

JoeHebda: I've bookmarked it. Since its a huge list, I'll look at it hopefully in the near future... Thank you.

Any recommendation guys? For example, something that will never 'go old' or 'die out'. Something that will last even after the death of our solar system...? E.g., the font "Times New Roman" is a goldie - although "Ariel" font is taking a peak for some time/years, Times New Roman font is still posh/graceful/historic/modern...if you know what I mean. I tried using Times New Roman font, but it lacks the 'forward looking' or 'futuristic/future looking' bit, if you know what I mean. -- Mr. Zoot Cig Bunner (talk) 19:04, 18 January 2016 (UTC)

3dcaddy, JoeHebda: Sorry about that guys, I did not mean to come across as rude...I used strikethrough now. Regards. -- Mr. Zoot Cig Bunner (talk) 19:28, 19 January 2016 (UTC)

If you want something that will never go old or die out and will last even after the death of our solar system, your best bet is to not write anything and just imagine/dream that you have a font that will last that long (even though we have no reason to think our current alphabet and language will last that long). Nil Einne (talk) 21:17, 18 January 2016 (UTC)

Nil Einne: Even better, then it'll look like ancient, historic, and futuristic - Alienatic - something like the Egyptian rubbish i.e. aliens came down to earth and bla, bla, bla...

I've already used my imagination. I have logo and a name - My drawing covers it nicely but I don't want my hand writing and drawing around the universe. My Father is not permitting it still, so I'm day dreaming and staying prepared...having fun in other words. -- Mr. Zoot Cig Bunner (talk) 19:28, 19 January 2016 (UTC)

January 17

Difference between ? and * in cron

At work, I have to use a .NET scheduler library that uses Unix cron expressions for scheduling. The documentation tells me that "?" means "any day/month" and "*" means "every day/month". What is the difference between these? Could anyone give a concrete example where "?" and "*" cause different schedules? Or do such conditions even exist? JIP | Talk 20:46, 17 January 2016 (UTC)

I looked in the Solaris, FreeBSD, and Linux cron(8) and crontab(5) man pages, and I don't see any of them ascribing any meaning to a ? wildcard. This seems to be specific to the fakey crontab your specific .NET thing does. -- Finlay McWalterᚠTalk 22:31, 17 January 2016 (UTC)

Indeed; the same applies to GNU mcron; the '?' symbol is not a documented feature of either type of cron syntax supported by the GNU variant. Your best bet is to check the documentation that specifically applies to your scheduler tool or library, because it evidently uses its own variation of the standard syntax. Nimur (talk) 22:57, 17 January 2016 (UTC)

I don't understand it either. Usually a "?" wildcard in a string means any ONE character whereas "*" means any string of characters. Bubba73 ^{You talkin' to me?} 23:30, 17 January 2016 (UTC)

Well, "usually on Windows"... but even then, use caution: '?' and '*' wildcard behavior varies wildly between the ordinary Windows command interpreter, the Windows Power Shell, Windows Power Shell "cmdlets", and third-party programs that run on Windows. Here's an MSDN blog on the difference in wildcard expansion between Windows and unix...; and even that doesn't mention the special case of cron syntax.

For what it's worth, our article on cron mentions that '?' expands differently on nncron, a proprietary freeware variant of cron developed for Windows. It even self-describes its '?' expansion as "non-standard." Nimur (talk) 02:32, 18 January 2016 (UTC)

cron syntax isn't a special case of shell filename globbing. It's a totally different thing. I guess it's possible that shell syntax influenced cron's use of * for "any value", but *2 doesn't mean any value ending in 2, etc. I don't know why Bubba thought there was any connection. -- BenRG (talk) 04:10, 18 January 2016 (UTC)

I thought so because of Wildcard character, but I admit that I don't know anything about cron. Bubba73 ^{You talkin' to me?} 04:47, 18 January 2016 (UTC)

On NetBSD UNIX, the crontab format is explained in crontab(5), i.e. "man 5 crontab", and this version does have a meaning for "?". It means that when reading the crontab file, cron is to select any one value randomly from the permitted ones. So for example "20 ? * * *" specifies that the job is to run once a day at 20 minutes past some hour: for example, it might be at 3:20 or 7:20 or 23:20. "? ? * * *" would run it once a day at a random time. Also, "?" can be followed (without spaces) by a range, which asks for a random selection from that range. "?40-42 * * * *" would run the job once an hour at either 40, 41, or 42 minutes past the hour.

Note that if cron ever rereads the crontab file, a new random selection will be made. So if you edit the crontab file, even if you did not change the entry where "?" was used, then this might cause your "daily" job to switch to a different time, perhaps causing it to execute a second time during the same day/hour/etc. (if it switched to a later time), or not at all one day (if it switched to an earlier time). Similarly if cron had to be restarted for some reason.

The man page points out that this feature is useful if the same crontab entry is used on a large number of machines and would cause each of them to connect to the same host, for example. --76.69.45.64 (talk) 05:26, 18 January 2016 (UTC)

January 18

Travelling with a Google Chromecast

Will a UK-bought Chromecast still have access to UK-licenced content in other countries? Thanks! 94.12.81.251 (talk) 13:46, 18 January 2016 (UTC)

Probably not. Much regional-licenced content filters by IP location. If your chromecast is in e.g. Brazil, it will have a Brazillian IP, and as such you have no clear rights to UK content. SemanticMantis (talk) 17:55, 18 January 2016 (UTC)

In setup, You choose a language. With the YouTube app, possibly the URL of the Video is foreward to the Chromecast when the connection to the adroid phone is establishedy only. --Hans Haase (有问题吗) 20:39, 18 January 2016 (UTC)

As SemanticMantis has hinted at, it would be more useful to ensure your ChromeCast connects via proxy than it would be to buy your Chromecast in the UK. Actually, I strongly suspect it doesn't matter where you buy it. Nil Einne (talk) 21:14, 18 January 2016 (UTC)

Partial specialization on a member class of a class template

I have a (third-party) broken iterator:

template<class T> struct Container {
  struct iterator {/*...*/};
  //...
};

It's broken in that it does not define the typedefs for std::iterator_traits. I can specialize std::iterator_traits myself to supply the correct (and obvious) types, but how? Writing

namespace std {
  template<class T>
  struct iterator_traits<typename Container<T>::iterator> {/*...*/};
}

fails because T is not in a deduced context. Of course, if Container::iterator were a typedef (not a member class), and/or if Container was subject to partial specialization itself, then the compiler might have quite a time determining if each subsequent instantiation of iterator_traits matched the "pattern". But the only simpler way to refer to that nested class than to give the canonical name of its containing class would be to use an alias template, which g++ 4.9.2 rejects on the same grounds. Is it simply impossible to produce such a partial specialization? --Tardis (talk) 17:13, 18 January 2016 (UTC)

I think it's impossible. The top two answers of this question may work for you: either fully specialize iterator_traits for all the contained types that you plan to use, or define an adaptor template with the appropriate typedefs. -- BenRG (talk) 20:00, 18 January 2016 (UTC)

Further searching (based on the idea that this is a general limitation of template deduction) finds the frustrating result that g++ used to do this but stopped to adhere to the standard. It's obvious that—when the nested name is constrained to be the real name of the type—the deduction is technically possible to implement, but the standard simply says no. --Tardis (talk) 00:32, 19 January 2016 (UTC)

NuGet question

My company manages most of its internal projects with NuGet packages. This goes so deep down that different .NET C# class libraries within the same product are referenced with each other through NuGet. So I have found out that if I have to make changes to a library referenced to by other class libraries, I have to first build it, then make and publish a new NuGet package of it, and then update all the references. When I say "publish", I mean we only update our internal NuGet repository. The packages only ever go to our company internally and our customers. But I find it a hassle to go through all this every time I want to modify the code in a class library. Is there an easier way to test the changes, before making an official update? My boss suggested temporarily removing the NuGet reference and replacing it with a direct reference, then undoing all this and putting the NuGet reference back in. But I find this a hassle too. Is there any easier way? JIP | Talk 20:58, 18 January 2016 (UTC)

Does having a phone service reduce available ADSL bandwidth?

My broadband relies on copper telephone wire. Does having telephone service take some of the bandwidth away from the Internet connection? Could I ask for the phone service to be disabled and get slightly faster Internet? --78.148.108.55 (talk) 21:39, 18 January 2016 (UTC)

ADLS and PSTN coexist, they use different frequencies so they don't "use up" each others bandwidth. Vespine (talk) 22:01, 18 January 2016 (UTC)

That's the theory, and is probably true in Edinburgh. In practice, if you are at the end of a six-mile stretch of copper, a phone call can make the ADSL stop working completely (for reasons other than bandwidth). It's worth asking your ISP. Dbfirs 23:00, 18 January 2016 (UTC)

I don't dispute what you're saying (it's common knowledge that ADSL's performance drops rapidly with distance), but this is kind of orthogonal to the original question. ADSL and phone service use different frequencies (the impetus for designing ADSL was to transmit data over existing phone connections by using frequencies above the voiceband frequencies), so disabling the phone service isn't going to add additional bandwidth to the ADSL service. The issue you brought up is interference between phone and ADSL transmissions, but unless you're using the phone, nothing is being transmitted over the phone connection. So, if you don't notice any impact on your ADSL connection when you're using the phone, cancelling the phone service isn't going to improve your ADSL connection. --71.119.131.184 (talk) 00:42, 19 January 2016 (UTC)

Is it even possible to cancel phone service (as opposed to just unplugging the handset) and keep ADSL? Always thought a phone line has to be live with a number assigned to it in order to carry data. 94.12.81.251 (talk) 11:44, 19 January 2016 (UTC)

No. Naked DSL is fairly common in some places. In the past, some ISPs even recommended it for VDSL2 in NZ. The phone line does need to be live of course, but there's no need for a PSTN service to be tied to it. One advantage with removing the PSTN service is presuming you're allowed to by your telco and building owner, remove any any extraneous wiring except to the DSL jackpoint. You can do something similar by installing a masterfilter at the phone line entry, with a dedicated connection from the masterfilter to the DSL; but how common these are varies from country to country and the work may be a little more involved (depending on your existing wiring and how far ou want to go). See e.g. [6]. Nil Einne (talk) 13:41, 19 January 2016 (UTC)

Many years ago, when I had a DSL connection, I was getting a poor error rate (not quite the same thing as poor bandwidth - but the effect was much the same) - and AT&T advised inserting some filters on the phone line. They supplied them for free - and it did fix the problem. I guess the problem is that while a phone shouldn't generate the higher frequencies that DSL uses, old-school phones aren't always that well designed - so maybe it does anyway. Tossing in a low-pass filter shouldn't have a downside - and it can definitely help. SteveBaker (talk) 18:32, 19 January 2016 (UTC)

January 19

IPv6

It is well-known that the 32-bit IPv4 ran out of addresses. But IPv6 jumps to 128 bits. Wouldn't 64 bits be enough, at least for an extremely long time? That would give each person on Earth more than 2 billion IP addresses. Bubba73 ^{You talkin' to me?} 03:29, 19 January 2016 (UTC)

IPv6 is not designed to be "exhausted". As in, someone gets address 1, followed by address 2, followed by address 3.... etc.... Having a much larger address space allows addressing strategies to be implemented which are not possible with IPv4, this is mentioned here IPv6#Larger_address_space. Vespine (talk) 03:42, 19 January 2016 (UTC)

Yes, but my point is that seems like overkill. Wouldn't 64 bits be enough for a very long time? Bubba73 ^{You talkin' to me?} 03:44, 19 January 2016 (UTC)

It depends on how it's used. Even if every light switch in your house gets it's own IP address, that won't come anywhere near using them all up, but they might use a system that isn't all that efficient as far as assigning every address. For example, the first of the 8 parts might be for the nation, the 2nd part for the state or province, the 3rd for the county, etc., the 4th for the IP provider, the 5th for the institution or business, the 6th for the individual location or homeowner, the 7th for a particular local area network at that location, and the 8th for a device on that network. (I have no idea if this is how they are actually allocated, this is just an example.) So, while this isn't very efficient as far as percentage of IP's used, it is highly efficient at being able to quickly find info, like the IP provider, from the IP address directly. A similar example is a car's VIN, which is longer than it would need to be, if it was a simple serial number. But then, if it was, you couldn't find out much of anything without looking that serial number up in a database. StuRat (talk) 09:25, 19 January 2016 (UTC)

Wait, so this means the final sad end to power-cycling my router to get around paywall article limits? :-) 94.12.81.251 (talk) 11:29, 19 January 2016 (UTC)

Not sure why there's all this theoretical talk. It's not like we're still in 1997. As our article says, the standard IPv6 subnet is /64. That means it doesn't matter whether you want an IP for every electrical and electronic device in your house; or just to your phone and computer. You should still get a /64 subnet at minimum to play around with. Most commonly, the way IPv6 is assigned, even if only your router (or some other single device) is going to get its own IPv6 address, you'll still end up with /64 subnet. In fact, anyone who may ever want it, e.g. an office or simply a sophisticated home user will probably be assigned multiple subnets (perhaps a /48), to make things easier. We still get 18,446,744,073,709,551,615 subnets (less due to the various reserved etc) so it probably isn't an issue. However if it IPv6 was 64 bit and we used the same scheme, we're not really that much better off than we are with IPv4 (we'd have 4,294,967,295 subnets less reserved etc rather than addresses). I'm not sure if a 48/16 scheme would be that much worse than 64/64, however I'm not sure it's really that much better either. I presume this sort of thing is at least partly what Vespine was referring to. There's some more discussion [7], [8] & [9]. Nil Einne (talk) 13:22, 19 January 2016 (UTC)

Actually on second thoughts, 48/16 would actually likely be a bit limiting. While 65535 hosts would be enough for most use cases, there are surely some cases when it's too few. However if you used 48/16 under a similar scheme to the way IPv6 works, you'd need those hosts to be in more than one subnets. Plus it makes IPv6 address#Stateless address autoconfiguration more difficult due to the significantly higher risk of collisions (and inability to simply use something like the MAC address). I guess you could use 96 bits and 48/48 or perhaps 64/32, but I wonder even more how much advantage there is over 64/64. Nil Einne (talk) 15:28, 19 January 2016 (UTC)

I probably should add that many people question the wisdom of giving out only a single /64 subnet to even ordinary home customers and suggest /56 or /48 be the default to all customers (and I think this is also what RIR assignment policies and RFCs generally suggest or assume). See e.g. [10] [11] [12]. I think the takeaway message from all this is that IPv6 is intended to move away from the idea of IPs being a scarce resource that need to be conserved (to be fair IPv4 didn't really start off like that either even if it was like that by the time IPv6 was being worked on let alone now); to the mentality that if there's any resonable possibility they may be needed, they should be assigned to ensure routing etc works properly and in particular, to prevent incorrect usage such as effectively further subnetting a /64. Nil Einne (talk) 17:22, 19 January 2016 (UTC)

128 bits "overkill"? 64 bits "enough"??

My memory is that as IPv6 was being finalized, a bunch of us were upset that it was going to use a fixed size at all; we were hoping it would be variable-length and more or less arbitrarily extensible.

If there's one thing we've learned, it's that arbitrary, fixed limits always become confining. No matter how generous they are at first, no matter how ironclad the arguments of the form "this allocation is so plentiful that every light switch in the solar system could have both a primary and a a backup address and we'd still have a factor of three left over" seem to be, sooner or later, somebody is going to have a brainstorm which lets us do something hitherto unimaginable, the only cost being that it allocates something incredibly wastefully, but "that's okay because we've still got more than enough". And soon enough, the hitherto unimaginable becomes the absolutely necessary, and "still more than enough" becomes "just barely enough".

See also Parkinson's Law (and its generalization), of course.

It may take ten years or more, but I'd guess we'll be seeing localized "shortages" of IPv6 addresses within our lifetimes. —Steve Summit (talk) 15:52, 19 January 2016 (UTC)

Thanks for saying it, Steve. I was, and still am, a huge fan of variable-length addresses. We can always pretend, by building layers and layers and layers of subnetworks inside of deeply nested NATs...

A perfect example of why the 128-bits isn't good enough: have a look at some of the recent history in high-performance computing research. There was a serious effort, some time ago, to make the individual CPU-cores network-routable, and in fact to use ethernet as a processor bus (...and why not! Ethernet was as fast, or faster, than existing bus architectures!) One could envision a day when every memory-word on every single machine could be individually and globally addressable - if the protocol provided for an inexhaustible address-space.

I sort of remember hearing this kind of theory being kicked around for the SiCortex and for the Niagara, and in some transactional memory-over-internet-protocol research papers, and so forth; I'll try to dig some of that up. This was serious pervasive massive parallelism at its best.

Nimur (talk) 17:56, 19 January 2016 (UTC)

I'd add that getting IPv6 implemented and widely accepted was a gargantuan struggle...it marked a huge change for the underlying mechanisms of the Internet. Given how little extra the additional bits added to the average packet size - it was worth making a change that would be finally, unhesitatingly, "enough" - so we never have to go through this again. While I agree that it seems unlikely that every human on earth will need a billion IP addresses - a similar train of thought got us where we are today. In the era where a PDP-11 computer cost $10,000, it was reasonable to say "there will never be as many computers as people on earth" and hence a 32 bit address was considered more than adequate. In my home, I have 4 smart TV's, 4 Roku boxes, 3 WiFi routers, 4 laptops, 2 desktops, 2 game consoles, 4 cellphones, a printer, two laser cutters and a dozen IOT devices. Maybe 40 addresses for me, personally, at home. So you can see that we made a horribly bad assumption when suggesting that 32 bits would be a "forever good" number. We simply don't know whether there will ever be a need for that 2⁶⁴ addresses. Suppose we wind up with self-replicating nanotechnological machines? We could very easily wind up with more than 2⁶⁴ of them and want them all to be individually addressable on the Internet. That might not be going to happen - but do you really want to have to go through another round of IPvN updates if that happens?

With 128 bit addressing, we could give a unique IP address to every molecule making up planet Earth - hopefully that's "enough"...but I'm with Steve Summit here - I'd have used a "high-bit-set-means-more-bytes-to-come" approach and thereby allow the address field to be infinitely extensible. Sadly, that worried people who have to be concerned about some idiot sending a trillion byte address and causing every computer on the planet to run out of memory...or making life too complicated for IoT devices. So, yeah - I guess the 'prudent' thing was to pick an ungodly large number. Just don't blame me if/when we need to give a unique address to every quark and photon in the visible universe!

SteveBaker (talk) 18:09, 19 January 2016 (UTC)

640k addresses should be enough for anyone! (Yes, I know Bill Gates didn't actually say the original "quote".) --71.119.131.184 (talk) 18:44, 19 January 2016 (UTC)

Any addressing scheme doesn't necessarily needs to work forever, just long enough for it to become obsolete for other reasons. For example, if the VIN system for identifying personal vehicles outlives personal vehicles without "filling up", then it served it's purpose. StuRat (talk) 19:32, 19 January 2016 (UTC)

OK, thank you for your answers. Bubba73 ^{You talkin' to me?} 21:32, 19 January 2016 (UTC)

Resolved

Intensive but short programming bootcamps

If I have one month's living expenses as savings, could I learn anything useful at a programming bootcamp in that time? I mean something pretty immersive, where I'd be coding full time instead of working a job. I know some Java already but I'm open to other languages. Location is Edinburgh, Scotland. 94.12.81.251 (talk) 11:34, 19 January 2016 (UTC)

I have been teaching programming in many (MANY) different environments since 1989. My experience is that people learn to program when they need to program. The best thing to do is have something you want to do and then do it. For example, you might want to learn Ruby or PHP. Both are popular web development languages. So, come up with a project and develop it in the language you want to learn. Since you already know Java, you know how to do what you want to do in Java. You just Google for how to do it in Ruby/PHP and keep looking at the code examples until you understand what is happening (such as "Why does PHP have all those $ symbols throughout the code!?"). That is how I have become proficient in so many programming languages. I am thrown jobs that people don't want to do, such as adding a feature to a flight simulator written in Ada. It doesn't matter that I've never used Ada before. I just have to look at some references and translate how I'd do it in C into how I should do it in Ada. 199.15.144.250 (talk) 16:29, 19 January 2016 (UTC)

Once you have learned the basics, (loops, functions, if statements, arithmetic, I/O) I don't think that programming classes/bootcamps will get you very far. You need to practice. You need to write MOUNTAINS of code. You also need a reason to do that. I always suggest learning enough JavaScript to write a simple web-based game - Pong or Breakout or something like that. Most people would like to make a simple game - and that makes it a better example to work on than something that doesn't motivate you as much. Ideally, you'd also want some kind of a mentor who could gently nudge you in the right direction when you get completely stuck. SteveBaker (talk) 17:24, 19 January 2016 (UTC)

If your plan is to brush your programming skills in just one month and then work as a programmer right away because you need the income, I am afraid that your deadlines are too tight.

On a brighter note, there is something positive about your case. In general, I think some people never learn to program. That sounds pretty harsh, but yes. No matter how much effort they invest into it, their programming sucks. Since you already learned Java and are willing to keep learning, you seem to belong to the other group, the one that learns to program. However, programming at a professional level requires more time.

There are other things you could try in the same field though. Having a logical mind, you could try other IT jobs: web-master or tech support, for example. [[Glasgow], not far from you, appears to be a a rising tech hotspot [13], with many jobs available [14]. Scicurious (talk) 13:47, 20 January 2016 (UTC)

Thanks for the support :-) I actually have closer to 2 months' savings, but I was leaving myself time to find another job afterwards. I already work in tech support, but it's call centre shift work and I'd like to move away from that if possible. Probably to desktop support in the short term. So I'll keep plugging away at the job applications, and mucking about with code in my spare time. 94.12.81.251 (talk) 18:05, 20 January 2016 (UTC)

Ripping DVD movies to ISO on one computer, converting them to MP4 on another

I have a stack of movie DVDs, an old slow Windows laptop with a DVD drive, and a much faster Mac without one. I want to get the movies off the discs so I can watch them more easily while travelling. Backing them up all the way to MP4 on the Windows machine would take weeks. Is there a combination of software that will copy encrypted DVDs to ISO on Windows, and convert ISOs to unencrypted MP4 movies on Mac? Something free if possible, naturally :-) 94.12.81.251 (talk) 13:46, 19 January 2016 (UTC)

• ImgBurn will turn your DVDs into ISOs. http://www.imgburn.com/
• VLC will turn ISOs into MP4s. http://www.videolan.org/vlc/index.html

https://wiki.videolan.org/Rip_a_DVD/ explains how rip DVDs in VLC, but I have never tried it because ImgBurn works so well. --Guy Macon (talk) 14:31, 19 January 2016 (UTC)

I've been using HandBrake (which I just learned works on Windows) to convert my old DVDs to MP4s on my wife's Mac. I've been thinking of getting a cheap optical drive to plug into my Mac to speed up the process with two systems doing the conversions. Just another idea for you: Get a cheap disc drive and plug it into the Mac to keep from doing two conversions. Dismas|^(talk) 18:25, 19 January 2016 (UTC)

(OP) Thanks! I settled on the 21 day free trial of AnyDVD on the Windows laptop, to to decrypt the discs on-the-fly so ImgBurn (free) can read them, and create ISO images. It takes 20-30 minutes even on this pretty old machine, so that works. 21 days is long enough to finish all the discs I've got waiting, but they have a 20% sale on until 24th January if anyone feels like buying. On the Mac I'm using Handbrake (free) to encode high-quality MKV files from the ISOs. It's fast enough to finish a movie at "veryslow" quality in about 90 minutes, and I can leave a queue running all night. Once I figured out I have to choose all my settings THEN create a custom preset to save them, I was fine :-) 94.12.81.251 (talk) 17:59, 20 January 2016 (UTC)

USB optical drives are fairly cheap now-a-days. LongHairedFop (talk) 19:36, 20 January 2016 (UTC)

Yeah I know, but I didn't feel like going out to buy one or waiting for a delivery. 94.12.81.251 (talk) 20:05, 20 January 2016 (UTC)

In a microchip, what are the physical equivalent of a head, state register, tape or finite table

In a logical description of an abstract machine (able to process information), there is an infinite tape and a head reading/writing and moving the tape left/right. There are also a state register and a finite table. What are the physical equivalents in a real microchip implementation? I suppose an approximation of the infinite tape would be RAM or HDD. And I also suppose the finite table is the instruction set. Is that right? What about the other two? --Llaanngg (talk) 15:54, 19 January 2016 (UTC)

It sounds like you're thinking of a Turing machine, but the vast majority of real processors use architectures nothing like a Turing machine, so I'd say looking for the head is futile. It might be kinda sorta similar to the program counter, but not really. —Steve Summit (talk) 16:04, 19 January 2016 (UTC)

In a classical Turing machine, the values on the type are somewhat like registers in a CPU. The registers in the CPU don't move around, so you don't need a head to read/write them. Further, the Turing machine stores more than values on the tape. It can store instructions as well. In a modern computer, the instructions are in a process control block, which is stored in memory, not the CPU. Technically, they tend to be stored in logical memory, where part is in a backing store and part is in physical memory, but it appears to be all real memory to the CPU. So, that would be like a separate Turing machine all together that sends information to the CPU. Trying to simplify a CPU down to a Turing machine requires you to ignore the complexities. However, it is good to comprehend how a Turing machine works because that is now linear programming works - which is how most people write programs. 199.15.144.250 (talk) 16:26, 19 January 2016 (UTC)

What they said. The Turing machine is an abstract model of computation, used for reasoning about computation. Real-world computer architectures are mostly practical versions of register machines, although there are some stack machines in use. --71.119.131.184 (talk) 18:37, 19 January 2016 (UTC)

A typical computer is only 'equivalent' to a turing machine in what it can do and what it can't. There doesn't have to be (nor often is) a direct correspondence between the inner functioning of one versus the other. Any computer (with sufficient time and memory) can emulate a turing machine - and a turing machine can emulate any computer. That's a demonstrable mathematical relationship - but it doesn't depend on their internal architectures. XKCD 505 has a great example of how one can imagine architectures for computation that look nothing like either a turing machine or a modern computer. THIS, on the other hand is an actual turing machine (albeit with only a finite tape) built out of Lego. But a system that's equivalent to a turing machine can be made from all sorts of elements. HERE is one built from model train tracks! SteveBaker (talk) 17:15, 19 January 2016 (UTC)

Modern computers are more Neuman machines than Turing machines. Ruslik_Zero 20:53, 19 January 2016 (UTC)

How does a webmaster program a forum?

What skills are necessary for a webmaster to program a forum? That is, create a working system that allows the end user to type something into a form and automatically see the result printed on the page? The webmaster acts as administrator and can moderate the postings, like a normal bulletin board/online forum. A webmaster may want to create a customized web forum, because the intent of the website may be different from the other types already on the market, or the webmaster may want to have full control over the look and function. 140.254.77.184 (talk) 20:14, 19 January 2016 (UTC)

Usually they would install software that has already been written, and then customise that with names, style sheets, set up users, groups etc. Drupal can do the job, but there are many others, see Comparison of Internet forum software. Otherwise the programmer will have to know about forms, POST method, user security, and databases to store the information on the server. From the comparison page you can see that the most popular language is PHP, and database MySQL. So the webmaster should learn these. Is this a homework question? Graeme Bartlett (talk) 21:13, 19 January 2016 (UTC)

Do you actually mean "program" as in writing a piece of software, or do you simply want to install existing software? There are tons of Web forum software packages that you can use "off-the-shelf". If you (or whoever) do actually want to write software, well, you need to have general programming knowledge first. Beyond that maybe Web programming will point you in the right direction. --71.119.131.184 (talk) 21:32, 19 January 2016 (UTC)

Turning over your question in my head a little more, it seems like what you might want to do is tweak an existing software package. A lot of forum software, CMSes, and the like allow you to extensively customize your installation, including the "look and function". It's unlikely you would need to write new software from scratch unless you really want to do something that's difficult to do with existing software. --71.119.131.184 (talk) 01:49, 20 January 2016 (UTC)

SQL max function question

Today at work, I spent over an hour puzzling over why my code didn't work. In the end, it turned out that I had written an SQL query in the form of select max(number) from table where this=that, which I thought was supposed to either return null or simply not return anything if there were no rows satisfying the condition this=that. But then I realised it returned 0. So I changed the query to abandon the max function and instead simply select number from table, in descending order, and changed the code to stop at the first result. Is there a way, in plain SQL, to make the query do what I thought it would? JIP | Talk 21:36, 19 January 2016 (UTC)

How about:

SELECT COUNT, MAX(W.NUMBER)
  FROM TABLE W WHATEVER
 WHERE W.THIS = W.THAT;

Then use a count greater than zero to indicate a match was found. StuRat (talk) 22:04, 19 January 2016 (UTC)

What database engine are you using. In Oracle, I get a single record with the value null. In MySQL/MariaDB, I get a null record. In MS-SQL, I get a single record with a null value. Perhaps you are using an interface like Ruby, Java, or PHP that is translating the value "null" into zero. 209.149.115.240 (talk) 13:16, 20 January 2016 (UTC)

There is a ternary operator in SQL. This should work, but I haven't tested if it's even legal SQL.

select case COUNT(W.NUMBER) when 0 then NULL else COUNT(W.NUMBER) end NUMBER from w

MS SQL Server also has the IFF function, if that's the server you are using. LongHairedFop (talk) 19:24, 20 January 2016 (UTC)

January 20

Representing bits in Magnetic Drum Digital Differential Analyzer

Magnetic Drum Digital Differential Analyzer says that it was the first machine to represent bits as voltages. I checked the reference, and it says that the machine was the first to use voltages for bits instead of pulses, as in ENIAC and UNIVAC I. I've always heard that a high voltage would represent a 1 and a low voltage would represent a 0. So I don't see the distinction between voltages and pulses to represent bits - can someone explain that? Bubba73 ^{You talkin' to me?} 19:35, 20 January 2016 (UTC)

I don't know much about it, but I think they might be trying to say that ENIAC/UNIVAC used AC pulses, and the MDDDA used DC voltage levels. Without access to the reference, I can't be sure. --Wirbelwind(ヴィルヴェルヴィント) 19:49, 20 January 2016 (UTC)

At least part of the reference is on Google books, but it has its own entry starting on page 163, which says "In contrast to ENIAC and UNIVAC, which used electrical pulses to represent bits, Maddida was the first computer to use voltage levels ..." Bubba73 ^{You talkin' to me?} 19:59, 20 January 2016 (UTC)