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March 9

I want the host to send PIO cmd only, how can I do it?

the way disable DMA mode is needed ,too . THX — Preceding unsigned comment added by Bruce sage (talk • contribs) 02:36, 9 March 2012 (UTC)

Are you sure you need to do this? Anyway, you can probably disable DMA in the BIOS settings. If not, if your operating system is Windows, you should be able to disable it from the adapter properties in Device Manager. -- BenRG (talk) 08:19, 9 March 2012 (UTC)

Hypervisors or virtual machine software that can perform signature checks on the VM it is loading

I like to play around with cryptography and I want to try on x86 platforms, but I don't want to buy a computer with a TPM (nor do I have the resources to buy a computer). So, is there any hypervisor, virtualization software, or emulator, no matter how obscure, publicly available, that can be run on a Mac, that provides such a feature? --Melab±1 ☎ 03:44, 9 March 2012 (UTC)

How are URLs containing semicolons handled by common web servers?

The semicolon is a reserved character in URIs generally but it doesn't seem to have a prescribed meaning in http: URLs. How do common web servers handle URLs with semicolons in their paths? Are they treated just like unreserved characters?

Here's info on how Apache interprets them[1] - it views them as a separator: the end of the URI, with parameters to follow. Other websearching suggests behaviour isn't particularly well defined in many cases. --Colapeninsula (talk) 11:54, 9 March 2012 (UTC)

Transferring HDD to new machine

I bought a laptop a few days ago; however, I'd just purchased a desktop about 8 months before that. If I just take the (larger) hard drive from the desktop and put it in the new laptop, will Windows sense it is on another computer and stop running? (I know that Ubuntu doesn't care; also, they are mutually compatible hardware types). Magog the Ogre (talk) 18:20, 9 March 2012 (UTC)

The desktop drive probably won't fit (physically). Next you have to deal with Windows Activation; it will definitely notice, but whether it just counts it as one of your handful of reinstalls or just stops you dead is a mystery. If the desktop licence is an OEM licence (rather than a retail install) it will probably refuse to run (or not: there are different kinds of, and different restrictions on, OEM licence types). If all this does work, you'll have to install a bunch of drivers for the laptop that the desktop didn't have (motherboard, display, eth, wlan, cardbus, storage, etc.) - and if that all fails, moving the disk back to the desktop will be ... another activation! I'd avoid doing this. 87.112.245.215 (talk) 18:55, 9 March 2012 (UTC)

I agree that a desktop hard drive just won't fit into a laptop. StuRat (talk) 22:41, 9 March 2012 (UTC)

To bypass that problem, you could of course use Norton Ghost or Clonezilla or a similar program to copy the contents of the desktop's hard disk to a 2.5" hard disk that will fit in the laptop. 87 is correct above, though; Windows may fail at the activation step (or may not). Comet Tuttle (talk) 02:09, 10 March 2012 (UTC)

I believe the OP wanted to use the larger capacity of the desktop's hard drive, so the issue isn't how to get it's contents onto the laptop, but it's capacity. StuRat (talk) 02:19, 10 March 2012 (UTC)

In reality, the OP (myself) does want to use the larger HDD capacity, yes, but he also doesn't want to have to go through the headache of reinstalling an operating system and its preferences (I mostly use Ubuntu) and reinstalling the games he uses on Windows. Magog the Ogre (talk) 02:29, 10 March 2012 (UTC)

In that case, you could put the 3.5" desktop hard disk into an external USB case and attach it to your laptop as an external USB device. Comet Tuttle (talk) 23:13, 12 March 2012 (UTC)

Cannot access one particular site (issue has persisted for months)

Hello,

For the past three months, I've been unable to access the main Project Gutenberg website (gutenberg.org). Prior to this, I'd never tried to access it, so I have no idea if it would ever have been accessible to me in the past.

I believe the problem is isolated to my router or whichever one of my ISP's thousands of servers I connect to (some sort of DNS problem, perhaps?), as I've tried hooking up different computers to the router and none of them can access the site (using the "ping" command elicits no response, too, so it's not a browser issue either). I've never had this problem with any other sites and Project Gutenberg loads properly at my workplace.

Is there anything I can try on my end to fix this, or will I simply have to make do with the Canadian and Australian Project Gutenberg sites (both of which load without incident)?

Any help would be appreciated.

Hiram J. Hackenbacker (talk) 20:36, 9 March 2012 (UTC)

1. Try http://gutenberg.ibiblio.org
2. When you ping www.gutenberg.org, what IP address does it show? Mine sees 152.19.134.47 (which is also gutenberg.ibiblio.org)

87.112.245.215 (talk) 21:09, 9 March 2012 (UTC)

Unfortunately, I can't connect to http://gutenberg.ibiblio.org. When I ping www.gutenberg.org, I get the following result:

Pinging gutenberg.org [152.19.134.47] with 32 bytes of data:

Request timed out.

Request timed out.

Request timed out.

Reply from 128.109.246.62: Destination net unreachable.

So the IP address matches your result, but no luck otherwise.

Hiram J. Hackenbacker (talk) 23:58, 9 March 2012 (UTC)

I've had this exact problem on other sites. It is almost certainly a problem with your ISP. Performing a traceroute to see exactly where along the line the connection drops (at the command prompt type tracert gutenberg.org) may help with diagnosing the problem if you decide to contact your ISP over it. 82.45.62.107 (talk) 21:27, 9 March 2012 (UTC)

I haven't previously heard of that command - good to know! I ran tracert on gutenberg.org and the result was the following:

C:\>tracert gutenberg.org

Tracing route to gutenberg.org [152.19.134.47] over a maximum of 30 hops:

1 1 ms <1 ms 1 ms mymodem [192.168.2.1]

2 11 ms 9 ms 9 ms 64.230.197.230

3 7 ms 7 ms 7 ms dis26-toronto63_Vlan107.net.bell.ca [64.230.229.105]

4 23 ms 21 ms 23 ms BX4-CHICAGODT_POS12-0.net.bell.ca [64.230.186.238]

5 20 ms 19 ms 19 ms Qwest-peering [64.230.186.206]

6 * * * Request timed out.

7 45 ms 43 ms 43 ms 65.121.156.210

8 41 ms 41 ms 41 ms ws7600-a1a-gw-to-wscrs-gw-sec.ncren.net [128.109.1.106]

9 44 ms 43 ms 45 ms chlt7600-gw-to-ws7600-a1a-gw.ncren.net [128.109.9.21]

10 * * * Request timed out.

11 * * * Request timed out.

12 * * * Request timed out.

13 * * * Request timed out.

14 * * * Request timed out.

15 * * * Request timed out.

16 * manning-gw-to-chlt7600-gw.ncren.net [128.109.246.62] reports: Destination net unreachable.

Trace complete.

What might this indicate? Clearly something's amiss, but I'm not sufficiently experienced in this area to interpret this information.

Hiram J. Hackenbacker (talk) 23:58, 9 March 2012 (UTC)

Although we're from different parts of the world, your packets and mine both pass through 65.121.156.210, and head through ncren.net (which is North Carolina based MCNC, which supplies UNC and other North Carolina education instutitions with internet connectivity). After 3 hops in ncren and one in UNC mine gets to the destination, but yours doesn't. Your 10th should be to manning-gw-to-chlt7600-gw.ncren.net (128.109.246.62) (which is MCNC's connection to UNC's IT center on Manning Drive). I don't know why it's dying there, but it looks deliberate - that UNC itself is blocking you. Your IP, or yor ISP, may have hosted someone trying to hack or DOS them in the past (and they've taken umbrage); or they're trying to do geographic or network load balance and they're failing. Its not your fault, not your ISP's fault. I don't know that there's anything you can do, bar try to get a new IP address. 87.112.245.215 (talk) 00:22, 10 March 2012 (UTC)

So rather than the "destination unreachable" you're getting from manning-gw, you should see the final two hops:

   irl-vlan1600-manning-loco.net.unc.edu (152.19.255.253)  
   gutenberg.ibiblio.org (152.19.134.47)

They're there, they're working fine, they just don't like you. 87.112.245.215 (talk) 00:35, 10 March 2012 (UTC)

Thank you for the thorough response. I'll reboot my modem/router combo and see if I can get a new IP address assigned to it (it's entirely possible that my current IP address was previously assigned to some malicious individual by my ISP) (Edit: I've since rebooted my modem, confirmed that it was assigned a different IP address, and tried to connect to gutenberg.org with no luck). Failing that, might it be worth contacting MCNC to inquire about this problem? (Their site's contact info page seems primarily catered to the educational institutions they support.) Hiram J. Hackenbacker (talk) 00:55, 10 March 2012 (UTC)

Project Gutenberg has the following disclaimer posted prominently in several pages on their site. "The Project Gutenberg website is for human users only. Any real or perceived use of automated tools to access our site will result in a block of your IP address." My guess would be that enough people with dynamic IP addresses in your range violated this rule so that Gutenberg initiated a rangeblock. If I were you, I would contact the Gutenberg team directly, either at help2010 at pglaf dot org, or webmaster at gutenberg dot org. However, you should probably do this from a webmail account, as mail originating from bell.ca may never reach them for the same reason you cannot establish a web connection. gnfnrf (talk) 04:20, 11 March 2012 (UTC)

Thanks for the suggestion; I'll send them an e-mail from work this week. Hiram J. Hackenbacker (talk) 14:50, 11 March 2012 (UTC)

Threat detected while sensitive information was visible - should I be scared?

While I had some sensitive information visible (in a form in Firefox), Avast reported "Threat has been detected". Should I be worried, and what is the recommended action? PurpleSorceress (talk) 20:44, 9 March 2012 (UTC)

If the threat was detected, it was probably also dealt with by your anti-virus software. For example, if a website is detected to be a threat, it likely refused to load that site. StuRat (talk) 22:38, 9 March 2012 (UTC)

Thanks a lot. That's what I was thinking, but I wasn't sure whether it might have done something evil before it got caught. PurpleSorceress (talk) 00:12, 10 March 2012 (UTC)

Most anti-virus software saves a log of what action it has taken. I don't use Avast, but it might be worth looking .... Dbfirs 08:02, 11 March 2012 (UTC)

Can't compile wxWidgets on Ubuntu 11.10

Upon running the configure script, I get this:

*** Could not run GTK+ test program, checking why...
*** The test program failed to compile or link. See the file config.log for the
*** exact error that occured. This usually means GTK+ is incorrectly installed.
configure: error:
The development files for GTK+ were not found. For GTK+ 2, please
ensure that pkg-config is in the path and that gtk+-2.0.pc is
installed. For GTK+ 1.2 please check that gtk-config is in the path,
and that the version is 1.2.3 or above. Also check that the
libraries returned by 'pkg-config gtk+-2.0 --libs' or 'gtk-config
--libs' are in the LD_LIBRARY_PATH or equivalent.

Trying sudo apt-get install libgtk2.0-dev does not find the package. --Melab±1 ☎ 23:13, 9 March 2012 (UTC)

There's not really enough information here to diagnose the problem. How about trying Synaptic rather than apt-get? It's a bit better at helping you to use the right repositories. Looie496 (talk) 04:15, 10 March 2012 (UTC)

You'll want to ask any Ubuntu-related questions on Ubuntu forums. They're much more experienced than we are in such issues.

68.232.119.30 (talk) 19:41, 10 March 2012 (UTC)

March 10

Forcing Windows to choose a static IP only on a certain wireless network

I am setting up a VNC server on a laptop for my mother so that I can connect to it remotely and troubleshoot her machine. The only way I know to do this is to turn on port forwarding on my router (WRT54G, fwiw). However, the router dynamically sets the IP address of each machine behind the firewall dynamically, so I don't have a machine to forward the port to.

I've tried to fix this by making Windows (Windows 7) automatically connect via a static IP address every time. It is successful at this, but with a caveat: it will try to connect to every wireless machine with the same IP. It does not seem I can set it to only connect to a given wireless connection via static IP, and another static IP or dynamic for others.

What can I do? 68.232.119.30 (talk) 00:33, 10 March 2012 (UTC)

I don't understand what you mean by "it will try to connect to every wireless machine with the same IP". Can you rephrase that? 87.112.245.215 (talk) 00:38, 10 March 2012 (UTC)

I believe the complaint is that the querent's mom's laptop will attempt to connect to the local coffee shop's wireless router with a static IP instead of accepting a dynamically assigned IP address. To the original poster: Are you sure you can't configure your mom's router to assign your mom's laptop a static IP address? I just checked my WGR614v8 router, which probably has similar firmware, and you do this on the "LAN Setup" page under "Address Reservation". Get this working, and the laptop can just be set up to accept a dynamically assigned IP address in all cases. Comet Tuttle (talk) 02:06, 10 March 2012 (UTC)

Comet Turtle has properly understood my complaint, yes. Oddly, I don't remember seeing that as a setting on the menu (I'm not on site so I can't check at the moment). If feasible, I assume this would be done via MAC address, correct? (OP) 98.235.166.47 (talk) 02:34, 10 March 2012 (UTC)

As an alternative, you might be able to set the DHCP server on the router to serve only a single address. Obviously this won't work with multiple clients, but would do if there's only a single device that uses the network.--Phil Holmes (talk) 11:47, 10 March 2012 (UTC)

Also, you could use the VNC server to "dial out" to your computer. That way, your Mom only has to click a "help me" icon, and it would start to connect to your computer. For this to work, you need a static IP or a dynamic DNS service provider, and a port forwarding for port 5500 on your router - but none on your Mom's router, and it would work from everywhere (coffee shop WiFi etc.), not only if she's at home. -- 88.67.157.60 (talk) 14:33, 10 March 2012 (UTC)

FYI, the router does not have an address reservation slot. But I may be able to get around the issue via port triggering. But I will have to find a utility online to dial out. 68.232.119.30 (talk) 19:37, 10 March 2012 (UTC)

If your usage will be non-commercial, you can install TeamViewer on the target laptop. It functions much like VNC but works from dynamic IPs and through firewalls, and is free for personal use. gnfnrf (talk) 12:20, 11 March 2012 (UTC)

Most routers will have no problem forwarding a port to a dynamic IP, as they will usually store the MAC adress to forward the port to. This means that if the laptop gets a different IP, the port forwarding is automatically updated and will still work. — Edokter (talk) — 12:28, 11 March 2012 (UTC)

Help me ID a former warez group member.

I've heard of this guy before, but I forgot his real name, alias, or as to what group was he from. All I know was he ran for public office in the U.S. after his stint at being a software pirate. Blake Gripling (talk) 03:55, 10 March 2012 (UTC)

Hm, this sounds suspiciously like you have actually have never heard of such a guy, and are hoping someone on the Reference Desk is ready to out a friend. Comet Tuttle (talk) 23:15, 12 March 2012 (UTC)

No, not really, I think I've read it here on a certain warez group article. Blake Gripling (talk) 09:29, 15 March 2012 (UTC)

EDIT 2 - That guy turned out to be Tony Krvaric, who's a former member of Fairlight and a San Diego Republican representative. Blake Gripling (talk) 09:29, 15 March 2012 (UTC)

RfC: What is the difference between information technology and computing?

The articles information technology and computing appear to be about the same thing.

Please help solve this problem and edit the articles, or join the discussion at RfC: What is the difference between information technology and computing?

Thank you. The Transhumanist 15:47, 10 March 2012 (UTC)

As a quick short answer, IT is about the computers themselves and computing is about doing things with them (primarily). An analogy is building a car or working on it to make it run versus driving the car. Bubba73 ^{You talkin' to me?} 17:22, 10 March 2012 (UTC)

And IT concentrates on data, whereas computing is more general. Bubba73 ^{You talkin' to me?} 20:35, 10 March 2012 (UTC)

Compiling if statements with final booleans

Hi everyone. I unfortunately don't understand the Java compiler as much as I would like to. Consider the following code:

public class MyTestClass {

public final boolean DEBUGGING = false;

public void doSomething() {
if(DEBUGGING) {
//several statements of code
}
}
}

As you can see, the code inside the if statement will never be executed. My question: Is the compiler "smart" enough to know the code won't be executed and exclude its corresponding bytecode from the application? I would think so, but if you put "bad" code in the if statement, like below:

if(DEBUGGING) { //final DEGUGGING == false
Object obj = "Test";
String test = obj; //won't compile without explicit re-cast to String
}

it won't compile, even though if the compiler doesn't create bytecode for the always-false if statement, what's inside shouldn't matter. I'm specifically interested in the behavior of the Oracle Java compiler, but would also be interested to hear whether compilers of Java and other languages differ on how they handle this. Thank you--el Aprel (^facta-_facienda) 19:50, 10 March 2012 (UTC)

Yes, because the bool is final the compiler won't emit code (which is essentially how one does conditional compilation in Java). I think that's part of the standard (and not just an obvious, but optional, optimisation). But this, as you note, doesn't allow you to have invalid code in the unexecuted section. When a a compiler builds a binary from a parse tree, it doesn't start at the top, but at the leaves, and fuses leaves. Sure, they could add support for this (for most languages the compiler has to walk back up the tree to look at containing blocks to resolve data references) but why would they? 91.125.155.37 (talk) 20:23, 10 March 2012 (UTC)

I'm confused. Did you mean the compiler will emit code?--el Aprel (^facta-_facienda) 20:32, 10 March 2012 (UTC)

No, it won't, but it doesn't know that it won't when it's generating a code fragment for the body of the if. Only once it's completed doing that will it evaluate the if and realise it can dump the code fragment it's just generated. 91.125.155.37 (talk) 20:45, 10 March 2012 (UTC)

According to what I understand about Java compilation, the above is very much correct. This is pretty much equivalent to:

if (false) {
  Object obj ="test";
  String test = obj;
}

The compiler doesn't have the intelligence we humans do. It can't deduce "this part will never be executed anyway, so it's not worth the bother checking the syntactic rules for it". It will check the syntactic correctness of every statement anyway. JIP | Talk 22:03, 10 March 2012 (UTC)

Actually, I'd say that a compiler that checks syntax for code whether it is going to be executed or not is more useful than one that excludes such code from checks. It is otherwise possible that an apparently minor change elsewhere in the code, which then meant that the code would be executed, would then result in a stream of error messages: not exactly helpful... AndyTheGrump (talk) 22:28, 10 March 2012 (UTC)

Consider: at a minimum, the compiler has to at least parse the <stuff> which follows JUST to know when it hits the matching }, right?

--184.100.83.209 (talk) 23:42, 10 March 2012 (UTC)

el Aprel's question is rather deeper than that; his code is lexically and syntactically correct, it only founders on Java's type semantics. So the fact that it errors gives a deeper insight into how the compiler works. The fact that C's #ifdef does allow any junk to be in a false section shows how how differently that works than Java's if(false) 91.125.155.37 (talk) 10:17, 11 March 2012 (UTC)

Not really: a conventional C compiler never gets to see the junk in the first place: the source code goes through the preprocessor first, which strips out all the junk, along with all the preprocessor operators. AndyTheGrump (talk) 14:06, 11 March 2012 (UTC)

Am I correct, then, that in C, code stripped out by the preprocessor only has to be lexically and syntactically valid, not actually pass compilation? Therefore, this should be valid:

#include <stdio.h>
int main(void) {
#ifdef NOT_DEFINED
  int a = 1;
  printf("%d\n", b); /* the variable is named a, not b */
#endif
  printf("Hello world!\n");
}

but this should not:

#include <stdio.h>
int main(void) {
#ifdef NOT_DEFINED
  Hello everybody! This is my first ever C program! Hope you like it... =)
  /* Syntax error: the preceding line has a right parenthesis without a preceding left parenthesis */
#endif
  printf("Hello world!\n");
}

JIP | Talk 22:17, 11 March 2012 (UTC)

As far as I'm aware, a C preprocessor knows nothing about C syntax: as far as it is concerned, it is simply processing a text file, substituting and omitting text based on preprocessor operators. Nothing else gets analysed at all. AndyTheGrump (talk) 23:03, 11 March 2012 (UTC)

Annoyingly, the C preprocessor knows tiny crappy bits of C syntax, which makes using it for other purposes (like an HTML macro expander) difficult. In particular, it knows about string literals, and elides adjacent ones, it knows about character literals (and so complains about things like 'foo' that aren't valid character literals in C). In some cases it also quibbles about character sets and even trigraphs. It would be much better if the preprocessor didn't do anything to lines that didn't begin with (spaces)# other than expand macros, but that's not to be. 87.115.67.78 (talk) 00:00, 12 March 2012 (UTC)

Ah yes - I've just dragged out my old copy of K&R, to check what exactly the preprocessor is supposed to do: a rather unfortunate combination of too much, too little, and things that should never be done at all. (Yes, like everyone else who's ever programmed in C, I've tied myself in knots trying to write clever macros, only to be frustrated by the arcane rules. I think it was this that finally convinced me that I was never cut out to become a professional programmer) AndyTheGrump (talk) 01:53, 12 March 2012 (UTC)

Sorry to show up late! The answer is, of course, "it depends." First, as has correctly been stated above, most standard Java does not use a preprocessor; though nothing forbids you from writing a Makefile and running the C preprocessor on your Java source files. So if you wanted to use C-style macros and ifdefs, that is possible, but fairly uncommon. As far as dead code elimination - yes, Sun Hotspot supports this optimization. If you're using the Hotspot compiler, now provided by Oracle, your "if false" block will be stripped during the compiler's optimization phase. Other Java compilers may support this optimization, but I'm uncertain if it's on by default in OpenJDK javac or in IBM javac. But, even in HotSpot javac, optimization occurs after compilation, so your "if false" block must still contain legal Java code, or it won't compile. Nimur (talk) 16:16, 11 March 2012 (UTC)

Actually, Dead Code Elimination is only available on the HotSpot Server Compiler (javac), (which is free to download, but is not free software). These optimizations do not appear to be available on the HotSpot Client Compiler nor on more recent Oracle Java SE 7 javac releases (or, they are present and undocumented). You might consider contacting the OpenJDK compiler-dev email list - details on their website - to ask them. If anyone on the planet knows which of the JavaEE compiler and VM internals made it into the OpenJDK javac, it'll be those folks. (As you're no doubt aware, "Server Compiler," "Enterprise Edition," and so on - the "marketing names" - got a bit munged up when Java migrated to Oracle; and a lot of the details of licensing changed, affecting the specifics of the open-source and free-to-use Java incarnations. Much of this knowledge is a bit buried behind corporate internals. Nimur (talk) 19:23, 11 March 2012 (UTC)

Advertising Malware on Wikipedia

Hi, I commented the other day on the Help desk [2] because I have large and obtrusive banner adverts at the top of every Wikipedia page I visit. I was directed from there to here, and the discussion on the 8 March with an IP user [3]. Unlike that user, I have run the malwarebytes free scan, but nothing came up (I have Norton Anti-Virus, which normally sweeps this kind of thing up no problem). Does anyone have any further suggestions - right now there are dancing iphones all over the place and I can't concentrate on the articles?--Jackyd101 (talk) 21:06, 10 March 2012 (UTC)

Try a different browser and see if that fixes it. I have Internet Explorer, Firefox, and Opera, myself, but Google Chrome and a few other browsers are also popular. You can download them all for free. StuRat (talk) 22:19, 10 March 2012 (UTC)

I've tried that and it does - but does this mean that I can no longer use Wikipedia on Firefox without adverts (which is comfortably my most prefered browser)?--Jackyd101 (talk) 11:54, 11 March 2012 (UTC)

If it doesn't show up in other browsers but does in Firefox then try disabling all Firefox add-ons (extensions and plugins). If that still isn't enough check the Firefox proxy settings (Tools, Options, Advanced, Network, Settings) and delete any proxy info that's unwanted. If that still isn't enough, come back here. Once you've worked out what the problem is, you may want to work out how it got there. And avoid relying on Norton to have to mop up problems in the first place by being more selective in what you choose to run or install. Nil Einne (talk) 13:58, 11 March 2012 (UTC)

Disabling the add-ons did it - I found three I didn't recognise, disabled them and the ads have disappeared. Thankyou very much for your help. As for how they got there, I have just got this laptop back from my cousin who borrowed it to take to university - I dread to think what he was doing with it. --Jackyd101 (talk) 15:06, 11 March 2012 (UTC)

Can you tell us the names of the add-ons? I'd like to know, since there seems to be a minor adware epidemic right now. -- BenRG (talk) 03:33, 12 March 2012 (UTC)

A process of elimination has determined that the one responsible for (or at least facilitating) the Adware was named "Silverlight plug-in". The other two I wasn't vcertain of, which I have since re-enabled without a reappearance of the adverts, were "Shockwave Flash" and "Shockwave for Director".--Jackyd101 (talk) 18:06, 12 March 2012 (UTC)

You mean Microsoft Silverlight?--Jac16888 ^Talk 18:16, 12 March 2012 (UTC)

I don't know for sure - I don't remember downloading it, which means my cousin probably did. The add-on is titled "Silverlight Plug-In 4.1.10111.0" and unlike all the others, has no description when you click on "more" - it doesn't say "Microsoft" anywhere on the add-on, and when I go to the Microsoft Silverlight webpage [4], it does not recognise Silverlight on my system and suggests that it install it. All I do know is that when it is enabled, Wikipedia is covered in banner ads.--Jackyd101 (talk) 22:59, 12 March 2012 (UTC)

Well my Silverlight which I'm quite sure is legitimate is basically the same so I don't think it's a help. However the Microsoft site should recognise Silverlight as installed provided the plugin is enabled. (If the plugin is disabled of course there's no way it will know it's installed.) Presuming the Microsoft site does not recognise Silverlight as installed even when the plugin is enabled I guess you at the very least have a fake plugin. If it does recognise it as installed, this doesn't prove the Silverlight you have isn't fake since it's likely a fake plugin could link to Silverlight in such a way that it will work while doing whatever dodgy stuff it does. On the other hand, if you have the genuine unmodified plugin which is also a possibility if the Microsoft site does detect Silverlight, this would actually be more concerning in some ways. It suggests you haven't actually found the problem but simply hidden one of the obvious signs as I guess the malware is using Silverlight to serve ads. Nil Einne (talk) 14:26, 13 March 2012 (UTC)

That is quite worrying - my anti-virus doesn't pick up anything at all. At least the ads are gone.--Jackyd101 (talk) 21:45, 13 March 2012 (UTC)

Discovering my password

If I am at a computer, under Windows XP, being the admin and connected to the Internet through a router. How can I see the password of this router? I have to connect another but have no idea how to see it. — Preceding unsigned comment added by 186.206.246.99 (talk) 21:14, 10 March 2012 (UTC)

If you don't remember your password, usually there is a reset that will set the password back to the factory default, which depends on who made the router. Bubba73 ^{You talkin' to me?} 21:52, 10 March 2012 (UTC)

They generally never display passwords, even to the Admin, as somebody could see it who shouldn't. Also, passwords might be dirty words and such that should be kept private. StuRat (talk) 22:17, 10 March 2012 (UTC)

For wireless routers or hubs, often the password can be found on a tag stuck to the device. Is that what you have? Looie496 (talk) 04:11, 11 March 2012 (UTC)

Solved! I whether needed reset, nor was it not displayed, nor was it attached to the device. I logged into the router through 192.168.1.1 using a standard password, and could see directly the wireless password. — Preceding unsigned comment added by 186.206.246.99 (talk) 04:46, 11 March 2012 (UTC)

Resolved

encryption

Is 7zips ASE encryption as good as true crypt? — Preceding unsigned comment added by 98.145.71.230 (talk) 21:57, 10 March 2012 (UTC)

If i understand correctly, 7zip encryption uses cbc, but truecrypt uses xtx, which means, that it is possible to access any part of data set directly (in truecrypt), but in order to access any random part of cbc encrypted data, all data before it must be decrypted first. Security wise they seems to be equal for most purposes. -Yyy (talk) 05:27, 11 March 2012 (UTC)

The short answer is yes. The long answer is "it's complicated". For example, to view or edit a file in an encrypted 7-Zip archive you'll have to extract it, which will probably store it unencrypted on your hard drive. Truecrypt doesn't have that problem. On the other hand, Truecrypt's volumes are accessible to all software when they're mounted, and some software might (innocently) save copies of your document elsewhere. 7-Zip archives don't have that problem. -- BenRG (talk) 07:31, 11 March 2012 (UTC)

Audio in/out

Hey gang, I hope you'll forgive my embarrassing lack of the right terms...

I have a Macbook Pro 13-inch, it has one "audio input/output" port. Is there any device that you know of that would allow me to plug in an input device (my bass with a 1/4 inch-to-8th inch adaptor) and then still have all the audio of the computer go to headphones?

My old computer had two ports and I liked to practice through garageband (a program on the mac) without disturbing my roomies.

So is there such a device that I could use?66.30.10.71 (talk) 22:17, 10 March 2012 (UTC)

I doubt it. It sounds like it must set the jack to either input or output mode inside, so you'd need to rip open the cover and alter the electronics to be able to have both inputs and outputs at once, if it's even possible. StuRat (talk) 22:25, 10 March 2012 (UTC)

There is such a device, but it doesn't plug into the audio port - it's called a USB sound card, searching for "USB sound card mac" should give you a large number of options to choose from (no idea if they are generally platform specific - but better to be safe than sorry). Prices seem to range from a few dollars for a bargain basement unbranded model with one input and one output, to a few hundred dollars for professional versions with about 8 outputs. Equisetum (talk | contributions) 22:45, 10 March 2012 (UTC)

It's better not to use a normal sound card's MIC or LINE ports, as the impedance doesn't match that of the electronics in a guitar or bass. To properly faithfully connect such an instrument, one should use a USB instrument adapter like a Behringer UCG102 (or one of the many competing brands; I know the Behringer works, but I don't have enough experience of the others to say it's any better). 91.125.155.37 (talk) 09:43, 11 March 2012 (UTC)

Explicit instantiation

In C++, why should explicit instantiation not use the 'inline' specifier? Also, am I correct in thinking that the purpose of explicit instantiation is to generate code for a specific template, so that it can be used in another translation unit? --140.180.0.112 (talk) 22:38, 10 March 2012 (UTC)

The answer to your second question is yes, and I think that answers your first question. (Inline functions have to be defined in every translation unit where they're used, which would defeat the purpose of explicit instantiation.) -- BenRG (talk) 07:36, 11 March 2012 (UTC)

How much for 13" MBP 2010?

I am looking to buy a used 13" MacBook Pro, from mid-2010, Intel Core 2 duo 2.4 Ghz, 250GB, 4GB RAM from a classified ad for $300. I'm not sure how much macbooks can resale for, but this seems a bit cheap to me. I fear it might be stolen, but the seller says 2 years of Applecare is still included on the laptop. Does the existance of Applecare on the laptop help verify its authenticity? Acceptable (talk) 23:43, 10 March 2012 (UTC)

I think that is does, since I also think that you can only buy AppleCare when you first purchase the device. — Preceding unsigned comment added by 85.211.130.94 (talk) 06:27, 11 March 2012 (UTC)

... provided, of course, that you can verify that the registered owner of the AppleCare is indeed the seller. Dbfirs 07:55, 11 March 2012 (UTC)

$300 sounds very cheap to me. A quick search on eBay revealed $900+ to be a more typical asking price. Maybe there's something wrong with it? - faulty in some way or stolen. Astronaut (talk) 13:29, 11 March 2012 (UTC)

March 11

Thick Margins

Hello. When I print a website more than one page long, my HP C309g printer squeezes the webpage out of proportion and allocates thick margins on the top and bottom of the paper even during single-sided prints even though Internet Explorer 8's Print Preview does not show me such margins. This is troublesome when I have to send commands to print divider tab inserts one piece of perforated paper at a time. Thoughts? Thanks in advance. --Mayfare (talk) 02:21, 11 March 2012 (UTC)

Sounds like a bad print driver. Try downloading and reinstalling, in case they've added a fix ? StuRat (talk) 03:03, 11 March 2012 (UTC)

Mozilla support newsgroups

I'm trying to use the Mozilla support newsgroups on news.mozilla.org, specifically mozilla.support.thunderbird and mozilla.support.firefox. I use Forte Agent newsgroup reader. I can read them fine, but noting I post shows up there.From my end it looks like my messages are sent, but they never show up. Is there some trick to getting them to show up there? Bubba73 ^{You talkin' to me?} 04:06, 11 March 2012 (UTC)

Are you sure new posts are supposed to appear immediately ? Many sites wait until they are checked by a moderator, at least for posts from new users. StuRat (talk) 06:21, 11 March 2012 (UTC)

The ones I have posted in the last several months never appeared. Bubba73 ^{You talkin' to me?} 15:34, 11 March 2012 (UTC)

Have the posts of others appeared ? If not, you may just have a dead board where the moderator has left. StuRat (talk) 18:32, 13 March 2012 (UTC)

Yes. Actually, my posts through Agent to Firefox get there, it is only the ones to Thunderbird. I tried deleting the Thunderbird folder in agent and adding it again, that didn't fix the problem. But I can post to the Thunderbird newsgroup from Thunderbird (but that is not how I prefer to get newsgroups.) Bubba73 ^{You talkin' to me?} 19:38, 13 March 2012 (UTC)

StuRat, he's posting to a usenet newsgroup; it's not a site and vanishingly small numbers are moderated in any way. Bubba73, before I read your last entry I was going to ask if you got usenet access through EasyNews, which by default does not allow you to post messages (you have to request it). Depending on how much you've tweaked Agent, it's possible you've messed up a setting for a particular newsgroup (or, just as likely, only fixed it for one). If it's not too onerous a problem, I'd consider uninstalling Agent and starting from scratch. You could also check settings to make sure they're (the groups, that is) set up identically. Newer versions of Agent are great, but the increased ability to fine tune each group's settings often just makes it that much easier to futz with something you shouldn't have - speaking from experience there! Matt Deres (talk) 14:50, 14 March 2012 (UTC)

There may be something wrong with the settings for that group, but I did delete the problem group and put it back in, and had the same problem. But this problem did start when I got a new computer (and a new version of Agent to put on it). Bubba73 ^{You talkin' to me?} 05:33, 16 March 2012 (UTC)

LaTeX font question

I'm aware that there are font commands for semi-bold and condensed font series, but I have yet to find a single font family for which these exist (I'm left with medium weight after using them). Does anyone know of a font family for which these series are defined, and distinct from medium weight/bold? I'm just curious what they might look like.--Leon (talk) 10:09, 11 March 2012 (UTC)

Removing extraneous seconds from WAV file

I recorded the background music of Trollie Wallie as a WAV file using VICE on my Fedora 14 Linux system. However, I accidentally stopped the recording too late, so now the WAV file has some extraneous seconds at the end where the music starts over again. How can I remove them? JIP | Talk 11:02, 11 March 2012 (UTC)u

I would use Audacity, which should be in Fedora's repos if you don't already have it installed. Simply open the file, highlight the section of the waveform that you don't want and press delete. Then File > Export to create a new WAV. AJCham 11:55, 11 March 2012 (UTC)

Audacity or, as you have the command-line-cojones for it, SoX 91.125.155.37 (talk) 11:51, 11 March 2012 (UTC)

Thanks, this worked. It's interesting to note that a WAV recording of a Commodore 64 chiptune taking a couple of kilobytes can be tens of megabytes in size. But this is of course because of fundamental differences in the format - a chiptune is machine language program, and thus can utilise programming constructs, whereas plain music formats must have every sound spelled out explicitly. A chiptune saying "play these notes ten thousand times" would not take much more space than one saying "play these notes twice". JIP | Talk 21:55, 11 March 2012 (UTC)

Debian installer preseeding issue

Hi, I'm having issues getting the Debian installer to do what I want.

Normally, I'd do this:

sfdisk -D -uM /dev/sda<<END
,3900,L,*
,3900,L
,3900,L
,,E
,3900,S
,,L
END

Which gives me the following disk layout:

sfdisk --dump /dev/sda
# partition table of /dev/sda
unit: sectors
/dev/sda1 : start=       63, size=  8000307, Id=83, bootable
/dev/sda2 : start=  8000370, size=  8000370, Id=83
/dev/sda3 : start= 16000740, size=  8000370, Id=83
/dev/sda4 : start= 24001110, size=288575595, Id= 5
/dev/sda5 : start= 24001173, size=  8000307, Id=82
/dev/sda6 : start= 32001543, size=280575162, Id=83

But when I to partition the disk using a custom "recipe" in a preseed file for an automated Debian installation, I always end up with crap like this:

sfdisk --dump /dev/sda
Warning: extended partition does not start at a cylinder boundary.
DOS and Linux will interpret the contents differently.
# partition table of /dev/sda
unit: sectors
/dev/sda1 : start=     2048, size=  7966720, Id=83, bootable
/dev/sda2 : start=  7968768, size=  7968768, Id=83
/dev/sda3 : start= 15937536, size=  7968768, Id=83
/dev/sda4 : start= 23908350, size=464488450, Id= 5
/dev/sda5 : start= 23908352, size=  7966720, Id=82
/dev/sda6 : start= 31877120, size=456519680, Id=83

fdisk -l
Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x000bb36a
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1         497     3983360   83  Linux
Partition 1 does not end on cylinder boundary.
/dev/sda2             497         993     3984384   83  Linux
Partition 2 does not end on cylinder boundary.
/dev/sda3             993        1489     3984384   83  Linux
/dev/sda4            1489       30402   232244225    5  Extended
/dev/sda5            1489        1985     3983360   82  Linux swap / Solaris
/dev/sda6            1985       30402   228259840   83  Linux

(Please ignore the varying size of sda6, one of my two test systems has a larger disk, and I'm simply telling it to use the entire remaining space for sda6.)

The custom recipe looks like this:

d-i partman-auto/expert_recipe string\
4080 4100 4100 ext3 \
	$primary{ } \
	$bootable{ } \
	method{ format } \
	format{ } \
	use_filesystem{ } \
	filesystem{ ext3 } \
	mountpoint{ / } \
	label{ BSYS } \
. \
4080 4100 4100 ext3 \
	$primary{ } \
	method{ format } \
	format{ } \
	use_filesystem{ } \
	filesystem{ ext3 } \
	mountpoint{ /foo } \
	label{ PROD } \
. \
4080 4100 4100 ext3 \
	$primary{ } \
	method{ format } \
	format{ } \
	use_filesystem{ } \
	filesystem{ ext3 } \
	mountpoint{ /bar } \
	label{ BETA } \
. \
4080 4100 4100 linux-swap \
	method{ swap } \
	format{ } \
. \
4080 300% -1 ext3 \
	method{ format } \
	format{ } \
	use_filesystem{ } \
	filesystem{ ext3 } \
	mountpoint{ /ney } \
. \

I've tried playing with the numbers, but no matter what I try, I always end up with the "Partition n does not end on cylinder boundary." crap.

What do I have to use so that the Debian installer does the same thing as my sfdisk command from above? -- 88.67.157.60 (talk) 11:36, 11 March 2012 (UTC)

(Solved with help from the German RefDesk) The solution is to add d-i partman/alignment select cylinder to the preseed file, which restores the old behavior. Cylinder boundaries are respected, thus, no more warnings, no more fatal errors in cfdisk. A newer cfdisk is said to be able to deal with partitions that don't match cylinder boundaries, so, who knows, maybe that parameter won't be needed any more in the upcoming Wheezy release and beyond. -- 88.67.157.60 (talk) 16:55, 11 March 2012 (UTC)

Resolved

Proxy servers

Are proxy servers legal in the uk?--WOLfan112 (talk) 16:38, 11 March 2012 (UTC)

Yes. Many businesses, schools etc connect via proxy servers, and ISPs often use caching proxy servers to save bandwidth and load times. 82.45.62.107 (talk) 19:35, 11 March 2012 (UTC)

But some activities, such as using a proxy server in a different country to get around location restrictions such as those used in iPlayer, may be illegal. Note, however, that the reference desk does not give legal advice, so if you need to know about a specific aspect of the law relating to proxies you should ask a lawyer (or at least your local Citizens' Advice Bureau). - Cucumber Mike (talk) 22:25, 11 March 2012 (UTC)

Tragically, the CAB is (in many areas, at least) so massively overworked right now that unless you're in dreadful debt, on the verge of being evicted or foreclosed, or in some terrible domestic violence situation, they're unable to find someone to see you. 87.115.67.78 (talk) 23:36, 11 March 2012 (UTC)

I think the law on this topic is sufficiently complex and new that the CAB would be unlikely to be able to help even if you could ask them - they claim to offer advice on "debt, benefits, employment, housing, discrimination, and many more issues" but internet/IP law isn't necessarily one of them[5]. --Colapeninsula (talk) 16:03, 12 March 2012 (UTC)

The asnwer is yes, proxy servers are legal in the uk, however using one for nefarious purposes can be illegal. Depending on what you are doing and what service you are subverting, the answer probably lies buried within the EULA or terms and conditions of the serice. But don't assume you're fine even if you can't find your specific purpose in those documents. In these circumstances, unless you know better and are willing to accept the risk, it's probably better to err on the side of caution. Vespine (talk) 02:20, 13 March 2012 (UTC)

March 12

Wireless fails at single hotspot

The wireless connection on my laptop (a Lenovo ThinkPad running Windows 7) works fine at home, work, the library, and the train. It does not work at a local lunch place; this has been going on for at least four visits over more than a month. The manager there says nobody else has complained and that it is a standard Comcast wireless router. The connection shows up on my list of available connections, generally with four or five bars, and lets me connect, but never successfully completes the connection. Other than eating lunch somewhere else, any suggestions? Ma^t_chups 10:33, 12 March 2012 (UTC)

It would be interesting to see what happens if you borrow someone's little USB WiFi dongle and try it with that. Obviously this shouldn't be necessary, but trying this tests several hypotheses:

1. that for some reason the Comcast router is blacklisting your MAC address (a dongle will have a different MAC)
2. that there's some weird setting in your wireless networking stack that's incompatible with the settings of the Comcast (you get a fresh set of settings with a new adapter)
3. there's just some darn incompatibility between your network stack and the Comcast (that's really clutching at straws, but you never know)

I wouldn't recommend buying a WiFi dongle just to test this, as these are all pretty long shots.

But apart from that, I'd suspect that the security software on your laptop (perhaps a personal firewall) is blocking some part of the login sequence - something that the Comcast does (that's valid, but unusual) that the other routers you visit don't do. So you can check the windows event log, and the firewall's log (if it has a separate one) to see if it's doing anything. From a purely diagnostic perspective, turning off the firewall might be instructive - but obviously I'm reluctant to tell you to turn off a firewall in such an environment. 46.208.220.25 (talk) 15:01, 12 March 2012 (UTC)

Lunch is a popular time. I wonder how many other people at the lunch place are also using the connection. Could it just be slow to respond and your PC thinks it has timed out? Astronaut (talk) 07:20, 13 March 2012 (UTC)

Codes for a Universal Remote Control

I have bought a second hand TV (a JVC) but had to buy a universal remote control for it. The codes that where in the little booklet that came with the remote didn't work so I thought I'd 'google' it instead. But all I can find are 3 or 5 digit codes, the remote I've got uses 4 digit codes. I've tried tvcodes.com & when I click on the jvc service link, all I get is a white screen. Can any one help me ? 80.254.146.140 (talk) 14:32, 12 March 2012 (UTC)

I know it sounds silly, but verify that the remote itself works okay (e.g. that the batteries are fine). One way to do this is to view the business-end through a digital camera, and confirm that it sees the infra-red LED light as you push buttons. Next verify you're doing the programming sequence correctly - these sequences are often rather mad (hold down this for three seconds, stand on one leg) - try programming the remote for a different TV you have access to (Sony is a good choice, as Sony have been extraordinary consistent about keeping their control codes compatible over decades - the basic volume/channel/1,2,3.. stuff for any Sony should run any other). If you can't control the Sony, you know it's you or the remote that's at fault. AS for your books.jvcservice.com link, that gives me a working website with a "Enter as much of the model number as you know" search box. 46.208.220.25 (talk) 14:46, 12 March 2012 (UTC)

Many remote controls also have an option to step through every code, and that could help you when the code is unknown. It may take an hour, so do it while doing something else, like using the computer. StuRat (talk) 00:10, 13 March 2012 (UTC)

Email address or a P.O. box of Mike D’Antoni

To whom it may concern,

Would it be possible to contact Mr. Mike D’Antoni (New York Knicks coach)by email or p.o. box as a fan?

Thanks,

Joe — Preceding unsigned comment added by 99.144.168.46 (talk) 15:14, 12 March 2012 (UTC)

There's an address here. --Colapeninsula (talk) 16:07, 12 March 2012 (UTC)

PHP and MySQL

Hi, I'm learning both PHP and MySQL and what I am trying to do is to search my database from a dropdown list on my webpage, for example it will have in the dropdown list a placename and when chosen it will return all the information from the database related to that placename. I am using XAMP for my server, can anyone point me to a tutorial where I can learn to do this. — Preceding unsigned comment added by 84.203.243.10 (talk) 16:33, 12 March 2012 (UTC)

First, I recommend using a MySQL PHP class for this; it's easier than coding all of the database lookup stuff yourself. There are a lot of them out there; this one seems pretty straightforward to me, though for a new PHP user the object-oriented stuff might be a little confusing, but just follow the examples.

Second, make sure you understand what an SQL injection attack is, and how to use mysql_real_escape_string() to sanitize any data received from the user.

Third, here's the basic scheme for what you want. Let's imagine you have one page with the dropdown, and another that receives the data. (Once you get the hang of the concepts, it's easy to make it all the same page.) The page with the dropdown will have an HTML SELECT element, filled with OPTION elements. All of this needs to be inside an HTML FORM element which directs the selected data to the script which receives the data, and specifies the form METHOD (either GET or POST). Add a INPUT submit button to the form, and you're good. The form data then goes to the PHP script. You access form data according to these instructions. What you'll want to do is grab the data from the FORM, and then create an SQL SELECT query based on its contents (don't forget to sanitize it!). Then you run the SQL query (see the MySQL class above) and output the data to the browser.

If you break the above up into small pieces, it becomes pretty easy — no one step is very hard. Once you've gotten the above working, it's a lot easier to see how you'd have the list and receiver pages being the same page (have just one page which checks for form data every time it loads), and from there graduate on to playing with AJAX queries (so the page doesn't even have to reload). --Mr.98 (talk) 17:37, 12 March 2012 (UTC)

Exponential algorithms

Are there any yes-or-no problems for which a solution can be verified in polynomial time, but finding the solution in polynomial time is mathematically proven to be impossible? I would use Google, but I don't know what terms to start with. --140.180.0.112 (talk) 20:35, 12 March 2012 (UTC)

First see NP-complete. NP-complete problems fall into that category, except that they have not proven to require exponential time (but they certainly seem to). Bubba73 ^{You talkin' to me?} 20:49, 12 March 2012 (UTC)

In fact, NP is defined to be precisely those problems that have solutions which can be verified in polynomial time. If it turns out that P = NP, no problems fit the OP's description. (But most experts think that there really are problems in NP that aren't in P.) Paul (Stansifer) 20:59, 12 March 2012 (UTC)

Regarding your subject line: note that there are algorithms that run in super-polynomial but sub-exponential time, such as the best known algorithms for integer factoring and graph isomorphism. -- BenRG (talk) 23:45, 12 March 2012 (UTC)

Force MinGW to install in Program Files

Unfortunately, I am a stickler for naming conventions. Is there anyway I can force MinGW to install in C:\Program Files? --Melab±1 ☎ 20:59, 12 March 2012 (UTC)

Chiptunes

Am I correct that a chiptune is usually (at least in the case of the Commodore 64) a small machine language program to instruct the sound chip? If that is the case, then I could theoretically be able to download PlaySID files from the Internet, load them up on VICE, and then type SYS something and the emulated Commodore 64 would play music. Is there any documentation about the internal structure of PlaySID files, or for that matter, D64 files? JIP | Talk 21:04, 12 March 2012 (UTC)

Hmmm. I have a SID synth but am far from an expert on the details. You're probably better off going straight to the c64 communities and forums for questions as specific as this.. Here are a couple I found: almighty c64 , sidplay and a page about the playsid format. Or even one of the many chip tune communities. Vespine (talk) 02:14, 13 March 2012 (UTC)

(Terminology: I think chiptune describes more how the music sounds, not what file format it's in. For example, a chiptune may be stored in a tracker file (a module file), which isn't machine language. Since you're really asking about SID files, it might be clearer to say "SID file" instead of "chiptune".)

I found documentation of the SID file format at the High Voltage SID Collection (FAQ 7). Browsing over the file format, it looks like the main data section is indeed machine language, but the headers can specify a few important addresses: load address (where to put the data in memory), init address (set accumulator to song number, then call this address to initialize a song), and a play address (call this address frequently to produce sound). The specification seems to say it's possible for the machine language data to include code that installs its own interrupt handler to keep calling its own internal play routine (in this case, the play address in the header is set to zero). But if there's a play address specified, I guess you'll need some auxiliary code (a SID player) to play the file. --Bavi H (talk) 04:04, 13 March 2012 (UTC)

Here are various file formats used by Commodore 64 emulators. If you want to experiment with loading machine language into your Commodore 64 emulator, may I suggest the much easier to use PRG format, described in the Binary link on that page. The first two bytes are the load address (low byte, high byte), then the rest is just the data bytes you want to load. (This is exactly what the contents of a PRG file on a Commodore 64 disk would be.) If I remember correctly, your emulator will let you select a folder of files to act as a disk (instead of a D64 file), then you can LOAD"FILE.PRG",8,1 then perform the correct SYS address if you know it (not always the same as the load address). Check your emulator's documentation to make sure. --Bavi H (talk) 04:46, 13 March 2012 (UTC)

Linux: why load environment variables when not using them?

A while back, while investigating a buffer-overflow bug in a C program, I discovered that the environment variables had been loaded onto the heap at launch, even though I wasn't using them and had declared only

int main (int argc, char **argv)

Doesn't it waste time and memory copying the environment variables onto the heap for a program that doesn't use them, especially when using a large number of small processes? Shouldn't the executable file have flags that indicate whether to load the arguments and/or environment variables, and shouldn't the compiler set these flags according to which parameters main() actually declares? NeonMerlin 23:29, 12 March 2012 (UTC)

How long do you think it takes a multi GHz microprocessor to copy a few hundred bytes of data, that is already in cache, into a page of process memory, that is already in cache? How much kernel and engineering effort should be devoted to a change that means processes will start, at most, a few millions of a second sooner? 46.208.220.25 (talk) 23:52, 12 March 2012 (UTC)

And just because you don't declare env as an arg to main, that doesn't mean the library calls you make don't use it anyway (by calls to getenv). 46.208.220.25 (talk) 23:55, 12 March 2012 (UTC)

In UNIX-like operating systems, new programs are started with fork-exec. The environment is simply inherited by the child created with fork(), which will give the new process a virtual copy of the old processes memory, and uses copy-on-write to make physical copies as necessary. All versions of exec either explicitly set a new environment, or keep the inherited one. In the latter case, the environment of the child process is shared with the parent until either is changed, so no unnecessary copying takes place. In the former case, you ask for an environment, so you get it ;-). --Stephan Schulz (talk) 01:25, 13 March 2012 (UTC)

March 13

SMS forwarding

Hi,

Does anyone know if it is possible to get a Windows Phone to forward sms messages to another number or to an email address?

The reason I ask is I'm thinking of going on a plan with a Nokia Lumia 800 which does not have coverage in rural areas and so there will be times when I will need to leave behind my Lumia 800 and take my old phone (which does have coverage). I would like to be able to be notified of any messages/missed calls I may get whilst I am away (note: in this scenario I would be leaving the Lumia 800 behind where it has coverage and hence able to forward).

Thanks for any advice! --Fir0002 01:56, 13 March 2012 (UTC)

Can you put the SIM card from the old phone in the Nokia? Maybe you will then have coverage. Astronaut (talk) 07:11, 13 March 2012 (UTC)

Unfortunately no - it's a limitation of the frequency band the Nokia supports --Fir0002 07:49, 13 March 2012 (UTC)

From reading the User Guide it doesn't appear to be natively possible. However, as always there's an app for that. There might be others, I just found that one after a brief Google search. - Cucumber Mike (talk) 13:00, 13 March 2012 (UTC)

That would be perfect but it doesn't support the new Windows Phone platform that the Nokia runs off (it only supports the old Windows Mobile and BlackBerry) --Fir0002 02:36, 14 March 2012 (UTC)

Alternatively is there a way to send an SMS auto reply? --Fir0002 08:36, 14 March 2012 (UTC)

great firewall of china

Is the only reliable way of getting around the firewall to pay for a vpn subscription? (If so does anyone have a recommendation?)

I also remember an online comment that sarcastically asked why anyone would actually pay for vpn. (Do they probably mean that there is some kind of free option?)

Thanks for the advice.

Momofukucakes (talk) 02:25, 13 March 2012 (UTC)

I've seen it suggested that China tries to block VPN traffic that goes thru the internet. [6] [7] [8] This can be done somewhat successfully with PPTP, L2TP/IPSec or just IPSec. It's more difficult with OpenVPN and SSTP given the difficulty distinguishing it from other SSL traffic in particular, HTTPS. (It would seem even blocking VPN traffic would cause problems for some businesses, perhaps they aren't so heavily restricted.) However if you use a commercial VPN service providing internet access, it's possible they may try to block all connections to these services whether now or in the future. The company may try to subvert this by changing the IPs but in an arms race against the Chinese government, I'm not sure they'll win. Particularly given that IPv4 addresses are running out or have run out (APNIC) so they'll probably have difficulty obtaining new ones. Nil Einne (talk) 04:35, 13 March 2012 (UTC)

Secret Facebook group problem

I administer a secret Facebook group for a youth organisation. A member accidentally quit the group and wants me to re-add her. When I try, Facebook tells me that once someone has chosen to leave a group, they have to personally request to be re-added. That, however, is impossible, because this person cannot see the secret group to ask to be re-added because she is not a member.

I was proud of actually finding the part of Facebook where I could report this problem some weeks ago, but have had no response, and the problem still exists.

Anyone got any ideas? HiLo48 (talk) 08:23, 13 March 2012 (UTC)

Arrange a time when you can both be online to briefly switch the group from secret to closed, have the ex-member request to re-join, then switch back to secret once more? It won't disclose the group's content, only its existence - and then, temporarily. 131.111.255.9 (talk) 09:00, 13 March 2012 (UTC)

Interactive voice response recommendation ?

I'd like something more than an answering machine at home. Specifically, I'd like the following:

1) Standalone system (not on my computer) answers all incoming calls on my regular US home line (not PBX or anything fancy) before the first ring.

2) It then plays a message I record and requires the caller to press a button to continue, hanging up on the rest. This is to get rid of robocalls, which I don't want filling up my answering machine.

3) It then plays another message I recorded, asking for a secret code. Those who enter the code can get the phone to ring. The rest may only leave a message.

4) At this point it should work like a normal answering machine. That is, after some number of rings, which I can set, it will then record the message. Ideally these messages would be recorded into a different inbox than those who didn't know the secret code.

5) A light or lights should light or blink to show when incoming messages are present.

I don't need voice recognition. So, can anyone recommend a system which fits the bill ? If it can't be done as a standalone system, I would then consider a system on my computer, but I would also need a way to get phone calls on the computer in the first place, which would work with the software. (My reasons for preferring a standalone system are that I find the Internet to be less reliable than a land-line phone, and I also don't want to leave the computer on 24/7.) StuRat (talk) 16:37, 13 March 2012 (UTC)

Google Voice provides something similar: you can turn on call screening globally, and then turn it off for groups of people that you know. You can also request that anyone being screened provide their name, which will probably defeat robocalls, since there's got to be a button press involved in that. You can have your messages (and their sometimes hilarious mechanical transcriptions) forwarded to your email if you like. However, I think that, if you have an existing land-line number, people who call it will always bypass Google Voice entirely (with mobile phones, you can arrange for Google Voice to intercept all incoming messages), so you'd need to publicize a new number (or go through a complicated process to port your landline number to Google Voice). Paul (Stansifer) 17:01, 13 March 2012 (UTC)

(EC) I don't understand the connection between the internet and a computerised system. There's no reason a computerised system can't use a landline and no reason the internet has to be involved. (Remember even your standalone system is ultimately some sort of computer.) If you're worried about space, look for an ultra small form factor computer. If you're worried about power usage, something like an Atom or perhaps an ARM or other embedded system won't necessarily be much more power hungry then a specialised system considering you only need 1. If you're worried about cost, while such a system will potentially probably cost US$100+ your needs are specialised enough that I expect it to be at least that. The other alternative is to buy a small old PC, these can be had fairly cheap in NZ so I presume the same in the US. It really depends how much work you want to put in it. Realisticly something like the much touted Raspberry Pi should be good enough since it doesn't sound like what you need is particularly demanding although I'm not sure how good driver support is for this sort of thing on ARM (I presume some people making Asterix systems have been using ARM based systems for a long time, but it may be some devices aren't properly supported). Although do bear in mind you need continous real time performance.

BTW, if you have ideas of doing this on Windows 98, I'm not sure I'd recommend it. *nix would be better and if you really want to use Windows, 98 just shows like a recipe for failure and problems.

Also your goals as stated do seem unrealistic. I don't believe it's possible to answer before any rings since any device needs at least part of the ring to detect there's an incoming call. Also I don't believe you can cause the land line to ring again after you've answered, unless the PSTN provider has provided some way of doing that. A better way of doing it that should work would be to connect the phoneline solely to your device so that no rings on the phone line are audible. Then connect any phones to the device so it's the device that causes them to ring when needed (and provides the voice). This does mean if your device fails you will get no incoming calls including in any power failure, although depending on how it fails, this can apply to any device connected to the phone line. (Note I say device here to emphasise whether you do it with a computer or a standalone device you should expect the same thing.)

As for software Asterisk (PBX) may be intended for PBXes but should fit the bill. I believe it's the most popular by far for anything like this, but there are other alternatives. As for hardware, a USB voice (analog) modem should be able to connect to the phone line and answer calls, as voice modems have been for the past 15+ years although you'll need to find one which works in the OS you choose. An Analog Telephone Adaptors can connect back to the POTS phones. According to our article, some ATAs do have a Foreign eXchange Office link (as well as a FXS link) so you should just need one device. From a quick search, an example which may be sufficient for your purposes may be this device [9]. According to [10] it should only cost about $65.55. There are other alternatives although I'm not sure if they're cost effective for a cheap home system such as yours [11] [12]. Perhaps there are dedicated Asterix embedded systems which would also be sufficient, you may want to look in to that.

P.S. As said, there's no reason the internet has to be involved at all, you can have the system completely disconnected most of the time for security. However having the device connected will allow fancy things like accessing the voicemail from other places without having to dial home, sending important mails by email etc. With additional services you could even do stuff like send text messages to your phone.

Nil Einne (talk) 17:31, 13 March 2012 (UTC)

A long while ago, when I bought my first modem so I could access the internet via dialup connection, the modem came with some call management software. I can't remember though if that was used to just configure the modem or whether the PC had top be left on for it to work. Maybe an old dialup modem is what you need. Astronaut (talk) 17:57, 13 March 2012 (UTC)

Alternatively, if it is "robocalls" or telemarketing calls, why not register your number with the National Do Not Call Registry? Astronaut (talk) 18:04, 13 March 2012 (UTC)

I have done that, but the evil politicians exempted themselves, and drove me nuts with robocalls when we had our Republican Party primary here last week. I don't want a repeat when the general election rolls around, later this year. StuRat (talk) 18:10, 13 March 2012 (UTC)

To clarify on the rings, I'm fine with a ring sounding on the other end of the line, before it picks up, I just don't want to hear it on my end, although an indicator light would be nice. Once they enter the code, I do want an audible ring at my end. If it can't make my phone ring, then it would need to make the ringing sound itself. StuRat (talk) 18:24, 13 March 2012 (UTC)

As for my motivation at not using a PC, there's the initial purchase price for a dedicated PC, the electricity used and heat generated, but even more worrisome is that every PC I've ever owned locks up and needs to be rebooted on a fairly regular basis (and it could be quite some time before I notice the need to reboot it). Thus I don't consider them to be reliable enough. I want this system to work 24/7, not just when the PC feels like it. StuRat (talk) 18:20, 13 March 2012 (UTC)

I don't know what type of magical box you are looking for, but I work on IVR systems all day long. They run on server class PC hardware. --LarryMac | Talk 18:39, 13 March 2012 (UTC)

So nobody sells an embedded IVR system which runs on it's own hardware, just like a normal answering machine ? Perhaps IVR is the wrong name for what I want, then. StuRat (talk) 18:43, 13 March 2012 (UTC)

You might be able to find a multi-mailbox answering machine with a priority caller or VIP feature that does some of what you want. For example, I found a manual for the AT&T 1726 Digital Answering System:

• This machine has three mailboxes and one greeting for all of them. So you could record a greeting that says "To leave a message, press 2". If no button is pressed, the message defaults to junk mailbox 1, but if callers press 2 the message goes to the safe mailbox 2. Unfortunately, in this scenario, you'd have to periodically empty the junk mailbox 1, and if callers don't pay attention to the instructions (or don't have a touch-tone phone), they may leave a message in the junk mailbox anyway. If you settle for this compromise, it might at least help filter your junk messages.
• The machine lets callers enter a 3 digit priority code during the greeting, and the machine will alert you. However, the manual doesn't say how long the alert lasts, only that the caller can press 5# to stop it and leave a message instead. (A similar model, the four-mailbox AT&T 1725 has a priority alert that lasts 30 seconds.)
• The machine has an option to remain silent during recording.

Further searching online may find other advanced answering machines with features that better fit what you want. --Bavi H (talk) 03:17, 14 March 2012 (UTC)

Thanks. Can it pick up before the first (audible) ring ? StuRat (talk) 03:19, 14 March 2012 (UTC)

I just read through the manual, and it looks like the minimum is 2 rings. I suppose I could turn all my ringers down or off, so they don't bother me while I'm asleep. The only problem is I don't know if the "priority tone" is loud and long enough to wake me, in the case of an actual emergency. This is my goal, to be immediately available to people I know, in an emergency, and never available to robocallers at all. And allowing robocallers to overflow my answering machine isn't good. (If it would just use a fixed allocation for the 3 mailboxes, they could then overflow mailbox 1 without messing up mailboxes 2 and 3, but that's not my reading of the manual.) StuRat (talk) 03:49, 14 March 2012 (UTC)

You're right, a full machine might be a problem, but the machine does store 40 minutes total (up to 119 messages), and enforces a 3 minute maximum per message (according to the troubleshooting item about incomplete messages). Just to be clear, I've never had this machine. I mainly wanted to point out searching for advanced answering machines may help you find a workable compromise. --Bavi H (talk) 04:35, 14 March 2012 (UTC)

Yes, but I hope there's some method quicker than reading through the user manual for each and every answering machine model. StuRat (talk) 04:38, 14 March 2012 (UTC)

As stated, the electricity usage and heat generated should not be a big use if you are careful with your hardware selecton. It's perhaps worth being realistic here. If for example your computerised system uses 27W all up average and your dedicated system uses 5W this suggests about a 22W difference. This isn't a small amount, but is easily equivalent to one CFL light on all day or 3 on for 8 hours. If this is still too much, you'll have to explore lower power systems. (I think even some Atom systems may be able to achieve under 20W and the ATA should add too much when not in use.)

In terms of initial cost, the answering machine you're discussing about seem to cost over US$100. If you shop around enough the computer hardware for a dedicated low power system should not cost more then $300 so at best you're spending 3 times. As stated earlier, your alternative option is choosing a perhaps slightly larger and less power efficient and risk of lower reliability refurbished small form factor older PC like those from offices and stuff. These are readily available here in NZ so it would be surprising if they aren't in the US.

As for needing to restart as LarryMac has hinted, people you need high reliability with downtime potentially costing thousands of dollars and do not want to have to restart once a year let alone regularly use computer based systems. And of course it's not just IVRs, but many servers out there and even most workstations. Of course if you don't want to pay the price for server class hardware suited for such extreme reliabilities (and from the sound of it, you'll likely need someone to administrate it for you anyway) you'll have to settle for slightly lower reliabilities. But even then, plenty of home users running Windows are able to get away quite successfully with restarting less then once a month and it's not uncommon to hear of people running home *nix systems who have restarted in many months or even years. I myself have a router (made from an aforementioned refurbished old PC) running m0n0wall which the only time it has had a specific problem was when the compact flash card died after many years. (I do restart it every so often when the internet dies for some random reason, generally along with the dedicated ADSL modem but this isn't necessary, I see no difference between restarts. Restarting is also needed by design when changing certain settings but this is similar to other home routers.) I can't say why you get such poor uptime but at a guess, user error and using old computers with Windows 98 probably plays a big factor.

Nil Einne (talk) 05:04, 14 March 2012 (UTC)

P.S. To clarify the uptime comment, remember there's broadly, two types of downtime you are probably concerned of here. One is a user or administrator controlled need for restart for hardware or software reasons. On a dedicated system for Asterisk, the need for this should be very rare and of course you since you are the user/administrator, you should know when it happens. The other is downtime due to temporary or permanent software or hardware failure. In this case you have little control although as stated choosing better hardware will help reduce the occurence. But even with fairly cheap hardware, the failure rate should be fairly low probably on average in the order of a year or more. To be informed quickly when such a failure does occur you'd need another system or systems which monitor the wellbeing of your voicemail system although with some temporarily failures particularly software ones, a well designed system should be able to restart itself. Note that this is no different from using specialised box except that your failure rate may be slightly higher. Nil Einne (talk) 05:29, 14 March 2012 (UTC)

Software/hardware/Safari conflict?

I hope I am in the right place. I get out of my depth pretty quickly in the technical stuff. I have edited sporadically since 2008, but lost access for several months. Now I am unable to log on. So far, with a lot of help from other users, I have determined that I am not blocked, and my email is enabled. I now have a new password which, as far as I have tried it, works under SUL on all projects except enWP, which is where I prefer to edit. My device is a Huawei M860M, using an Android OS and a Safari browser. I have the firmware version, kernel version and build#, but I'm not finding the Safari version, which I think to be critical after reading of default rejection of cookies by recent Safari browsers. I am attempting to contact Huawei about loading another browser, if possible. Maybe Apple or Google would be a better use of my time. I've recently been able to log on to enWP at a library, using the new password, reinforcing my idea of a browser problem. Will be back with more info. the Ragityman 69.171.187.73 (talk) 21:22, 13 March 2012 (UTC) 17:49, 13 March 2012 (UTC)

open source or free video editing

Hello,

What is the best free video editing software for me to get. I would really like Adobe Premiere but I do not have any money. I am not enormously computer-savvy so would prefer if it was something that is semi easy to use. I am running Windows XP. Thank you very much.

Anthony J Pintglass (talk) 19:03, 13 March 2012 (UTC)

Unfortunately there are not something of comparable power as Premiere that is simultaneously free and easy to use, in my experience (movie editing software is still a heavily non-user-friendly area, and the various open source options are, in my experience, either too bare-bones in what they do — e.g. just let you splice together existing movie clips — or impossibly, baroquely complicated). Your best bet is probably to try and get Windows Movie Maker, which is available free with XP as part of Service Packs 2 and 3 (you may even have it installed on your computer without realizing it). --Mr.98 (talk) 20:39, 13 March 2012 (UTC)

Hello, yes, I have this. I am looking for the next step up. Thank you for your help. Anthony J Pintglass (talk) 22:05, 13 March 2012 (UTC)

The next step up is a big one, to full non-linear editing systems. I've never seen one that I would describe as user-friendly. Take a look at the programs listed in that link, though, under free and/or open source. I've played around with a few of them, but in my experience they are very unintuitive. --Mr.98 (talk) 02:05, 14 March 2012 (UTC)

Problem with Pywikipedia

Hello. I've set up Pywikipedia to work on a third-party wiki and the bot itself seems ready to go. Nevertheless, I get the following message: No JSON object could be decoded. And the bot never gets around to editing the wiki. What can I do to solve this problem? Thanks.--Leptictidium (mt) 19:05, 13 March 2012 (UTC)

Does the Wiki in question implement m:API? Try wget 'http://your.wiki.wonk/w/api.php?format=json&action=query&titles=Main%20Page&prop=revisions&rvprop' (substitute whatever URL the API lives at) and see if you get a proper JSON object. You can roughly recognise JSON by nested curly braces and "key":<value> pairs. --Stephan Schulz (talk) 07:17, 14 March 2012 (UTC)

Animation3d PDN

2 questions

1. How do you get the plug that makes animations in Paint.NET to work?
2. How do you get the plug that makes 3d in Paint.NET to work?

Rply soon.74.178.186.35 (talk) 21:30, 13 March 2012 (UTC)

Copied from WP:RD/M. Nyttend (talk) 21:35, 13 March 2012 (UTC)

March 14

mobile AIM/trillian

So, recently I asked after sending text messages to a friend's AIM account, and it seems that is only possible on an android phone (though if you know different, do tell me) now, though, I want to try getting AIM at all on my phone, which is some cheap samsung phone on tesco mobile, so nothing special or helpful in any way. Can I download AIM and use it to exchange messages with people? Also, my trillian account keeps offering to let me get that on my phone as well, if I do, can I commmunicate through all its added accounts without having to download them all onto my phone as well as my computer?

148.197.81.179 (talk) 02:32, 14 March 2012 (UTC)

Drawing with JavaScript

At http://www.numberempire.com/graphingcalculator.php, the scrolling and zoom features appear to be implemented using a script on the web page (rather than going back to the server to generate a graph). Is that right? Roughly speaking, how is it done? Are there a bunch of JavaScript functions available for drawing graphics or something? It has been a long, long time since I wrote any web page scripts, but I don't remember that feature being available. Is it something relatively new? 86.160.82.40 (talk) 02:59, 14 March 2012 (UTC)

That page uses the canvas element. See that entry for a JavaScript example. You used to have to draw things in JavaScript using divs. (see http://www.p01.org/releases/Drawing_lines_in_JavaScript/). You still do have to use divs, in fact, if you want to support Internet Explorer 8, 7, or 6.—Best Dog Ever (talk) 05:53, 14 March 2012 (UTC)

CDC 6600 - which generation?

Was the CDC 6600 a (late) second-generation computer or (early) third generation? Bubba73 ^{You talkin' to me?} 05:22, 14 March 2012 (UTC)

This would seem to depends on your definitions for computer generations and would potentially be a matter of semantics. Presuming you're using the definitions used in Fifth generation computer, History of computing hardware, History of computing hardware (1960s–present) and [13], it would seem to me the CDC 6600 should be 2nd generation since from what I can tell, it did not make use of integrated circuits. It's also listed in List of transistorised computers. Nil Einne (talk) 05:37, 14 March 2012 (UTC)

cut and paste

Hi. kubuntu/R/libreoffice 3.4.4. I've just made a nice little histogram in R. How do I easily include this in my LibreOffice Writer document? Picking up the window and drag-and-dropping into LibreOffice would be great, but doesn't work. Using png(file="~/f.png");hist(x);dev.off() in R, then "insert" -> "picture" -> "from file" works, but is too much hassle to do a few dozen times. There must be an easier way. Anyone? Robinh (talk) 08:44, 14 March 2012 (UTC)

LGA1155 and graphics

if i'm buying an icore processor like say i5-2320 with integrated graphics, does it require my motherboard to have an integrated video chip aswell? IF not then how do i connect my monitor to it if my motherboard doesn't have any dvi-dub interfaces??? or if a motherboard has a dvi-hdmi-interface it doesn't necessarily mean it has a built in graphics chip???