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September 29

Two hardware questions

Hello Refdeskers! I have two separate but related questions:

1. As you may be able to tell from my userpage, my computer is a piece of junk that can barely run more than one application at a time. So I've been planning a major motherboard upgrade to the following components: AMD Athlon II x3 440, 3.1 GHz, tri-core CPU; 2 GB of RAM; and the integrated ATI Radeon HD 4200 graphics chip all on an Asus M4A785-M motherboard. (Of course other components will be upgraded, but they are irrelevant to this question.) The power supply is rated at 250 W; I plan to keep that as is. My question is: does the Reference Desk, in its infinite wisdom, think this is enough power to watch and record HD video? I was told on another forum that a 2 GHz dual-core Pentium would probably be enough, but I would like to make absolutely sure before I buy anything (and this particular CPU is on sale!).
2. I recently appeared on a local TV show. This particular show is only broadcast on a local station in my area, but there are family in other parts of the U.S. that would like to see my appearance. I plan to record the show in Windows Media Center using an HDHomeRun, but then there is the problem of actually getting the recording to the relatives. Right now I plan to burn the show to DVDs and mail them out (obviously ignoring the potential copyright issues) but since that is a bit cumbersome and involves cost on my part, is there a better, preferably free way that someone in the same situation has tried before? The show is 30 minutes long and produced and broadcast in 1080i HD, so we're talking very large (~2 GB) file sizes here. Xenon54 (talk) 01:39, 29 September 2010 (UTC)

For (2), you can use Dropsend [1] or a similar service to send fairly large files (up to 2 GB, in Dropsend's case). This is only feasible if you and the recipient have reasonably speedy internet connections. Buddy431 (talk) 02:10, 29 September 2010 (UTC)

For (2), why not just ask the show's producers for several copies of that particular episode? I've been on a few local programs in my time and the staff was always happy to provide copies for myself and some relatives. That's a very common request. You may have to pay a small fee for their trouble, but to me that seems the easiest solution and you won't run afoul of any legal restrictions. Just give em a call and ask! The Masked Booby (talk) 03:21, 29 September 2010 (UTC)

Yes that is more than enough CPU power to watch and record HD video, although you should probably look at getting 4GB (2×2GB) of RAM instead. The power supply seems woefully inadequate - even my old computer bought in 2002 had a 300W PSU! 250W means it's either very old or proprietary for small form factor (or both) and I doubt you can even use it on modern hardware at all. Pick a modest (eg. 400W) PSU from a reputable brand, they aren't that expensive anyway.

As for (2), you can also host the files on your computer and get your relatives to download it directly from you (use a VPN like Hamachi if you want a little bit more privacy), but that'd require you leaving your computer on most of the time. If they don't have fast internet access you could perhaps use a flash drive as a medium instead of DVDs to reduce costs and transfer times, maybe establish a family sneakernet or something. --antilived^{T | C | G} 03:32, 29 September 2010 (UTC)

If it's a quality and real 250W ATX2.0 (i.e. decent 12V) PSU I suspect it could power a modern hardware. See for example what some 300W can power [2]. I'm not saying I recommend it Nil Einne (talk) 11:13, 29 September 2010 (UTC)

See also the second last post here [3] of a system running a picoPSU-160-XT which is a DC-DC converter which takes 12V and outputs the other necessary voltages (3.3V, 5V) and rated at 160W typical, 200W peak. You may also be interested in looking at real world (i.e. not theoretical) measured usage of various systems under maximum possible power usage load that people can achieve. Nil Einne (talk) 12:15, 29 September 2010 (UTC)

OK, so I found a 380W power supply for $20 from Newegg and I'll upgrade that. What would you say the lowest I can go is in terms of CPU? In order to save money I'm looking at a 3.0 GHz dual-core Athlon II instead of the tri-core. Would that be enough power? Xenon54 (talk) 22:13, 29 September 2010 (UTC)

I don't know what PSU you are looking at but that sounds rather cheap and looking at PSUs at that price on Newegg I didn't see anything that particularly inspires confidence. I did find [4] which should be a decent enough PSU. I'm not saying it's the cheapest decent PSU you can find, I didn't look that well and I'm not familiar enough with all I saw anyway (I come from NZ where there's less choice).

Cheap crap PSUs have a tendency to die much sooner then better quality ones. Far worse though is they can kill hardware when they die. Well I suspect all PSUs have a chance of doing so even if technically the ATX standards say they shouldn't, but cheap crap PSUs tend to do it a lot more then better ones. Since you're buying a relatively cheap system, this perhaps isn't quite as big a deal as those who buy super expensive systems then use crap PSUs but worth considering. Another important thing is cheap crap PSUs can also have problems giving a reliable supply leading to stability problems (whether from the beginning or as they die). Cheap crap PSUs also tend to be overated, so often you might as well get a decent but lower rated better PSU (380W isn't that high but I saw some 300W which would potentially be better then a cheap crap 380W).

You may also want to consider efficiency. You can get a 80 PLUS certified PSU (not the earlier linked one I think although its efficiency probably isn't to bad) for example the Antec Earthwatts 80 PLUS [5] or the Corsair 430CX [6] (not certified but the manufacturer says it's primarily because they have submitted it and it should meet the standards [7]). Note again I'm not saying these are the cheapest high efficiency PSUs they're just ones I came across (the Antec I looked for since it's one of the cheapest 80 PLUS PSUs here in NZ).

I'm not sure what the efficiency of the cheap crap PSUs are but it wouldn't surprise me if they are around 70% or even less at certain ranges especially the lower ranges e.g. 20-50% (where your computer is likely to be most of the time) which means more heat and more power used (i.e. more cost to you). [8] says 72% for one cheap PSU but doesn't specify at what output. The efficiency savings are unlikely to be enough to make up for the difference but the price may difference may not be as big as you think over time. For example if your power supply is 70% efficient at 100W it's drawing 142.86W vs one that is 82% efficient at 100W that's drawing 121.95W or 20.91W difference. If you take 8 hours per day of that, that means a saving of 167.25Wh a day or 61.087kWh a year. I don't know how much you pay for power but since you live in the US from [9] 11 cents/kWh is probably not unresonable so a savings of $6.72 per year on your power. 100W is probably a little high, I suspect your computer will be close to idle most of the time it's on but even so a few dollars savings per year is probably not unresonable.

In terms of the CPU and HD playback (which I think is primarily what interests you? Recording is largely irrelevant of course presuming your are referring to recording digital broadcast TV), you haven't specified what sort of HD content you are talking about. If you are talking about terrestrial HD broadcasts in the US, AFAIK most well probably all of these are MPEG2 which isn't really that demanding even in HD. In any case, but particular for H264 it's IMHO worth using the GPU instead of the CPU. The HD4200 does hardware decoding for H264, MPEG2 and VC-1 so it should be fine if set up properly and with the right codec. From memory, the HD4200 needs a hypertransport 3 (well greater then 1400mhz hyper transport I think) CPU for all the PureVideo goodies to work at their best although I think that's primarily an issue for stuff like quality deinterlacing rather then hardware decoding and AFAIK all Athlon II CPUs have HT3.

In any case, a decent dual core should also be fine even if you do use CPU decoding provided it's an efficient codec and although as I've said that wouldn't be my recommendation anyway. One instance where you may need CPU decoding is with likely copyright infringing downloads, as these may occasionally be encoded with settings the GPU doesn't support (although nowdays I think most are avoiding that especially given playback on game consoles where you have no option). Bear in mind certain programs like VLC on Windows don't support multithreading anyway so there's no advantage to a triple core over a dual core at the same speed in that sense or even a single core really (well some minor advantage due to background processes perhaps).

Nil Einne (talk) 07:35, 1 October 2010 (UTC)

Microsoft Windows update frequency

My PC is about 3 years old and runs Windows Vista. I like to know what is installed, so pretty much as soon as I got it I configured Windows update to download and let me know about updates (I know that's not Microsoft's recommendation, but I like it like that). When I first got the PC the updates came often, almost every day in fact. Recently I've noticed the updates have become much rarer (perhaps every 2 weeks) but there's usually several updates to be done at the same time. My PC is still reporting it is up to date, so has Microsoft changed the way in which Windows update works to reduce the frequency of updates? Astronaut (talk) 04:10, 29 September 2010 (UTC)

see Patch_Tuesday 194.39.218.10 (talk) 05:17, 29 September 2010 (UTC)

As the article says, Microsoft issues patches for Windows every second Tuesday of every month. However, some days there may be less updates that other days, so maybe that's whats happened to you. Chevymontecarlo - alt 06:45, 29 September 2010 (UTC)

No, I don't think it's that - Patch Tuesday was introduced in 2003. When I said recently I meant with the last few months. Indeed, if I look at the history of updates on my PC I can see for example in April 2008 I got updates on the following dates: 2, 3, 6, 10, 13, 15, 16, 18, 23, and 24. Updates continued in this fashion until March 2010 (which had updates on 2, 6, 10, 12, 14, 15, 25, and 31). Since then, updates have only been received twice a month so last month I got 1 update on 3 August and 17 updates on 13 August. Astronaut (talk) 09:57, 29 September 2010 (UTC)

I've noticed the same with my updates of Vista (which I do manually for connectivity reasons). I'd assumed that Microsoft were losing interest in Vista. Dbfirs 07:30, 30 September 2010 (UTC)

Remember, though, that there's much less to patch when it comes to Vista. Service Pack 1 was 434 MB! And then they had SP2, which was another 348 MB. Windows XP's SP2, in comparison, was 266 MB. I'd imagine there's not much left to patch.--Best Dog Ever (talk) 07:44, 30 September 2010 (UTC)

Agreed. When an operating system first comes out there are lots of things to fix, but it's been 4 years since Vista came out so I think it's not unreasonable to assume that the fact the patches are less often is literally because there are less things left to fix. Remember the updates don't (generally) add new features, they usually require you to upgrade to a newer version of Windows for that, the updates are just to fix problems with the existing software.  ZX81  ^talk 17:25, 30 September 2010 (UTC)

There might be something in this, but I would have expected a gradual tailing off of updates rather then a sudden reduction to a couple of days a month. Then again, the change in frequency reduction seems to have started 6 months after the retail release of Windows 7 in October 2009 - one could speculate 6 months might be a significant time step in Microsoft's update/support policy. Astronaut (talk) 07:05, 1 October 2010 (UTC)

Video WB correction

Hi,

I want to perform some white balance correction on some video footage and am wondering if anyone had any software recommendations?

Thanks! —Preceding unsigned comment added by 58.175.33.162 (talk) 07:54, 29 September 2010 (UTC)

I'm not sure, but you could probably try Adobe Premiere or a similar, lower-budget program. --Belchman (talk) 12:36, 30 September 2010 (UTC)

Can't access a certain website

Hello wikipedians, I see to have problems accessing one particular website - www.monash.edu.au and anything under that domain. It's a rather large university so i doubt it would be down constantly and http://downforeveryoneorjustme.com/www.monash.edu.au/ says it is up for everyone else. I'm at a loss to why this one particular website doesn't work, when i go on it or any other pages under that domain i get the "Unable to connect" page in firefox.

I've checked the hosts file and thats all fine. I'm an administrator on this computer, no viruses that im aware of (why would they target that site anyway), i checked my MTU was 1500.

I recently (~3 months ago) upgraded to ADSL2+ and got a new router, not sure if i had problems before then.

I checked the router settings and there doesn't seem to be any blocking on this website.

I tried a laptop connected to the same home network im on and it had the same problems, this is a fairly new laptop so i doubt it is my singular computer.

Any ideas? —Preceding unsigned comment added by 121.219.139.24 (talk) 08:51, 29 September 2010 (UTC)

Have you tried accessing it from a proxy? Sir Stupidity (talk) 09:05, 29 September 2010 (UTC)

Yes i have, i thought i put that in the post but i forgot to hit edit i guess ((using a proxy such as http://www.proxyforall.com/ makes the website work, i just checked. I'm not sure if this because it encrypts the URL names in some fashion or because it has a different IP or something totally different)) —Preceding unsigned comment added by 121.219.139.24 (talk) 09:11, 29 September 2010 (UTC)

Try flushing the DNS. Also try a traceroute to see if there's a problem somewhere between your computer and the host. Assuming you're on windows here's how or use this 82.44.55.25 (talk) 10:13, 29 September 2010 (UTC)

Try http://130.194.11.149. As with many webhosts, they use some sort of virtual server so this won't lead you to the main page but I think it should work even without any DNS. If that does work, then it may be some sort of DNS issue. While testing this, I also found Monash has an AAAA record for their website. If you have a misconfigured IPv6 setup then this could also be the cause as many browsers default to the AAAA. Try turning off IPv6 for the network adapter and see if this helps. Nil Einne (talk) 12:21, 29 September 2010 (UTC)

Yes, that worked more than it has been working, the IP address. I could actually see the title in firefox and the page but it was text only, no images. As far as im aware i dont use IPv6(Except with utorrent but thats tunneled through something i think). Flushing the DNS did nothing, thanks for the idea though. Here are the trace-route outputs Monash , google(as reference) wikipedia(reference)

Sorry but if uTorrent is using IPv6 then IPv6 is enabled. Whether it's using Teredo tunneling or whatever is somewhat irrelevant since uTorrent still I'm pretty sure relies on the IPv6 stack of your OS. While I don't think it's a problem in this case from the traceroutes, it's likely worth disabling it for the network adapter when troubleshooting.

Anyway from the traceroutes, the problem may be because your trying to connect to the server 32.1.3.136. This is odd since from a lookup both locally and via a public web nslookup services it appears that the correct address is 130.194.11.149. It's possible I think that there may be some reason for this, e.g. they use a different server or some sort of cache for your ISP but I wonder if it's a problem with your ISP. I find some discussion of 32.1.3.136 primarily related to Ubuntu servers in Australia perhaps with Telstra. I also see some suggestion that disabling IPv6 may help in a few cases although this appears to be with Ubuntu, but you may want to try it just in case (I don't really see why it's relevant here since you seem to be getting an A record).

I would suggest you try setting your network adapter (or router) to use some other DNS server like Google Public DNS. Once you've done so make sure you flush your DNS cache etc as suggested above. If the problem goes away, and then returns when you use your ISPs DNS server again, it seems likely there's a problem with your ISPs DNS servers (they're giving you a IP for the server which either isn't the proper one or isn't working). Therefore in that case and if the problem remains after a few days, I would contact your ISP and tell them. Even if the problem isn't technically their fault but is caused by the Monash or some other NS server providing their NS server strange records, it's likely easier for them to work out what's wrong. (If your up to it, you could try querying Monash's NS server yourself and if it works, see what A record they give you for www.monash.edu.au.)

If the problem doesn't go away when you use a different DNS server, are you sure you haven't set a funny IP for Monash in your hosts file?

Nil Einne (talk) 22:52, 30 September 2010 (UTC)

World daylight map - free screensaver?

Where could I find a free screensaver that shows which part of the world is in daylight, like this image http://wwlln.net/TOGA_network_global_maps.htm Thanks 92.15.9.254 (talk) 13:12, 29 September 2010 (UTC)

This is not necessarily a screensaver, but possibly a preferable set of images: http://www.fourmilab.ch/earthview/.

—Wavelength (talk) 14:41, 29 September 2010 (UTC)

Something like EarthView or else play with this google search. --Tagishsimon (talk) 18:10, 29 September 2010 (UTC)

I've followed this tutorial to get daylight background map with clouds on my FreeBSD GNOME desktop with Xplanet. --Dereckson (talk) 23:51, 29 September 2010 (UTC)

hard drive

Is this hard drive about to fail [IMG]http://imgur.com/wZy7X.gif[/IMG] —Preceding unsigned comment added by 174.139.74.140 (talk) 14:45, 29 September 2010 (UTC)

That is a symptom, but not necessarily a guarantee, of "imminent" hard-disk failure. See our article's list of S.M.A.R.T. attributes for some context. The long answer is that statistical analysis of hard-disk failures indicates that these SMART attributes are weak indicators of potential failure - many times, their data is not a very good predictor of failure. Nimur (talk) 21:02, 29 September 2010 (UTC)

The indicators tell you if something is abnormal, but with the robustness in modern hard drives the question becomes "will that little problem ever become a big problem?" and the answer may be no. I have had several hard drives fail while giving off SMART warnings, and in all cases I was able to recover the data gracefully and have them returned for warranty. Ignoring the SMART errors probably would have put the data in jeopardy if I simply waited until the drives completely failed. If the disk is under warranty by all means get it replaced when *any* SMART error comes up, that's why drive makers offer such long warranty periods (3 to 5 years is typical.) With all that being said, I have had a drive give off the exact SMART error you are seeing; I took it out of primary service and use it as a temporary bulk storage drive and have not had it deteriorate in about 2 years of use. It does exhibit occasional 'hiccups' due to the spin problem whereby it will not transfer data for a few seconds, but it doesn't lose or corrupt data. So, ask yourself what your definition of "fail" is... --144.191.148.3 (talk) 15:34, 30 September 2010 (UTC)

IMHO, if the data on the HDD is valuable to you, either replace the HDD or make regular data backups. If the HDD is still under warranty, exchange the failing harddisk for a new one. Waiting until the harddisk actually fails can cost you money or the loss of valuable data. Rocketshiporion♫ 03:11, 3 October 2010 (UTC)

I think both of you guys are over-exaggerating. How old is this drive? I have five HDDs in my PC -- some of them a few months old -- and HD Tune Pro gives the spin-retry count on each one as "100." I saw another screen shot in the manual of a drive with a retry count of 249. Also, you don't have any re-allocated sectors. I've seen screen shots with a high number of re-allocated sectors. But, then again, there is nothing in the data column for any of my drives. Nor does it say "warning." Instead, it says, "ok" for the status. Do you get any more info when you click on "Log"? It should tell you in plain English that you have a damaged HDD if that's the case. Nevertheless, I would recommend backing up your hard drive. In fact, I recommend that everyone backs up up their hard drive. You don't have to replace it, though.--Best Dog Ever (talk) 22:39, 3 October 2010 (UTC)

Ping Localhost

When I try and ping localhost I get this:

Pinging Unknown-PC [127.0.0.1] with 32 bytes of data:
Request timed out.
Request timed out.
Request timed out.
Request timed out.

Ping statistics for 127.0.0.1:
    Packets: Sent = 4, Received = 0, Lost = 4 (100% loss),

The internet is working fine. I started Apache and browsing to localhost in Firefox works fine too. What is going on here? 82.44.55.25 (talk) 15:32, 29 September 2010 (UTC)

All that means is your computer isn't responding to ping. No big deal. -- kainaw™ 15:43, 29 September 2010 (UTC)

I know the computer isn't responding to ping; I want to know why, and how to fix it. 82.44.55.25 (talk) 15:53, 29 September 2010 (UTC)

What is your operating system? Do you have a firewall running? Do you have SELinux running? -- kainaw™ 15:58, 29 September 2010 (UTC)

The computer is Windows 7. The standard Windows firewall is running, and I haven't changed any settings there recently. I tried disabling the firewall but ping still doesn't work. I don't know what SELinux is, but I'm pretty sure I don't have it. 82.44.55.25 (talk) 16:01, 29 September 2010 (UTC)

In Windows 7 it is almost always the firewall. See here. -- kainaw™ 17:01, 29 September 2010 (UTC)

I tried disabling the firewall but ping still doesn't work. I added a new "Inbound Rule" as the guide you linked to suggested, but again ping still doesn't work. I can ping everything BUT localhost - pinging google.com works as normal for example. 82.44.55.25 (talk) 17:19, 29 September 2010 (UTC)

Why do you want to ping 127.0.0.1, anyway? It's pretty pointless. You already know that the machine is up.—Emil J. 10:26, 30 September 2010 (UTC)

Pinging localhost should work. The fact that it doesn't indicates a problem with the computer. I want to resolve it in case it leads to something else which does effect the computer in a more serious way. 82.44.55.25 (talk) 10:46, 30 September 2010 (UTC)

Microsoft considers responding to a ping to be a security flaw. So, it is disabled. It should NOT work on Windows 7. If it does, you have done something to the computer that Microsoft considers to be weakening the computer. -- kainaw™ 12:08, 30 September 2010 (UTC)

Is this right? We ping Windows 2003 servers all the time to see if they are up. Has the default changed? If so its something we will have to take into account when we upgrade (and change from the default setting or find some other way of testing for a server's presence). -- Q Chris (talk) 13:16, 30 September 2010 (UTC)

Ok, so how do I enable it then? From the first time I installed Windows 7 2 years ago I've been able to ping localhost without altering any settings whatsoever. This problem has only started in the last few days. 82.44.55.25 (talk) 13:28, 30 September 2010 (UTC)

The server is being delivered with a bit different default settings than Win7 for home users. It is assumed that home users will be inherently unsafe with their computers. So, ping is disabled in many areas of the computer. The firewall blocks it by default. Many other services block it, such as the AGN filter interface. Further, if you stop the firewall, it disables the network interface by default (that took a long time to figure out). You have to keep the firewall running, but set it to disabled. We simply don't try to ping Win7 on desktop machines. It isn't worth the trouble to get them to respond. -- kainaw™ 13:28, 30 September 2010 (UTC)

I don't understand. If ping is disabled by default, then how can I still ping everything except localhost? I can ping google.com, en.wikipedia.org etc and they all respond as normal. I've completely disabled the firewall (here is a picture) and it's still not working so it can't be the firewall causing this. 82.44.55.25 (talk) 13:42, 30 September 2010 (UTC)

google.com, en.wikipedia.org etc have not disabled ping on their servers. This has nothing to do with settings on your computer.—Emil J. 13:51, 30 September 2010 (UTC)

I haven't disabled ping on my computer either. It was working until yesterday 82.44.55.25 (talk) 14:04, 30 September 2010 (UTC)

(outdent) Don't confuse a ping host with a ping server. When you run the ping program to check on another computer, you are running the ping host. The other computer has a ping server that responds. When you ping localhost, you are having the ping host on your computer try to talk to the ping server on your computer. In Win7 set up for homes, Microsoft has gone to great lengths to stop the ping server from responding. They block it with the firewall. They block it with network filters. They renamed it to "echo server" so people won't find it. They don't have it running by default, so you have to go into network services and start the echo server. Even after all of that, every update seems to find another way to stop the server from responding. -- kainaw™ 13:50, 30 September 2010 (UTC)

Can you help me enable it again then? I don't know what has turned it off, I have windows update disabled and I haven't changed or run any new programs in the last few days. Disabling the firewall hasn't worked, and adding the rule exception you linked to earlier didn't work either. What are network filters? How do I start the echo server? 82.44.55.25 (talk) 13:53, 30 September 2010 (UTC)

Kainaw I think you are wrong. Surely Windows 7 would enable a user to ping their own computers loopback device, even if it blocked all incoming ping requests from external sources. Indeed, Microsoft themselves recommend pinging localhost as a way to test TCP/IP connectivity. 109.193.227.56 (talk) 14:57, 30 September 2010 (UTC)

Two things.

1) That article is for Windows XP. If you visit it with Windows 7 or Windows Vista or some other OS you will get "This article applies to a different version of Windows than the one you are using. Content in this article may not be relevant to you.Visit the Windows...". Microsoft can of course change their minds about how to do stuff.

2) While I don't know if Kainaw is correct, it sounds like Kainaw is saying Microsoft is wanting to make it difficult to enable responding to echo requests, by doing various things including disabling the actual server. This isn't possible if you want to be selective. Microsoft may also be concerned about possible bugs in their implementation of localhost only so prefer not to try (in particular, by disabling the server by default, it's one less server which could have bugs and which could be exploited). Microsoft may also be concerned that by enabling it for local host, people may get confused (I can ping myself, why can't others ping me). In other words, there are several reasons why Microsoft would want to disable it for everyone including local host.

Nil Einne (talk) 21:52, 30 September 2010 (UTC)

So how do I enable pinging localhost again? And what has caused pinging localhost to be disabled after 2 years of working? 82.44.55.25 (talk) 22:01, 30 September 2010 (UTC)

Why? Possibly a program accessing the the internet decided that it could not allow you to ping your computer. Or an Windows update has also in the process stopped you to ping it. Sir Stupidity (talk) 07:56, 1 October 2010 (UTC)

I don't run any Windows updates, and I haven't run any new programs recently. How do I enable pinging localhost again? 82.44.55.25 (talk) 10:02, 1 October 2010 (UTC)

Perhaps you should re ask the question again as everyone thinks this issue has been resolved. Sir Stupidity (talk) 07:42, 3 October 2010 (UTC)

I don't know if we think this issue has been resolved. I didn't but I wasn't sure how to help. Nil Einne (talk) 06:16, 4 October 2010 (UTC)

My laptop runs Windows 7 and it responds to pings directed at 127.0.0.1. The Windows firewall is turned on, too. Usually, when I can't ping 127.0.0.1, the computer won't connect to the Internet. In such a case, I usually re-install TCP/IP. (See this article for more information.) However, as the OP said, his connection is working. So, if it isn't broke, I wouldn't try to fix it. They could break something else while trying to fix the ping issue.--Best Dog Ever (talk) 07:23, 4 October 2010 (UTC)

free touchscreen software like a whiteboard to save handwritten documents

hey, i wanted to use my laptop like a notebook in uni lectures, but it doesn't seem t ohave software already instlled to do that. in school we used to have interactive whiteboards at the front of the class and the teacher would digitally write on that and be able to save each virtual sheet. and many sheets could be open at one time, and the each sheet could be scrolled down to the bottom and extended. the software they had is exactly what i want, but i think it came with the interactive whiteboards and i want somthing that's free... or i don't mind downloading illegally if it's easy to find to download. thanks for any help! 192.150.181.62 (talk) 18:40, 29 September 2010 (UTC)

What kind of laptop do you have? Is it a tablet? Looie496 (talk) 18:48, 29 September 2010 (UTC)

Yeah, a HP TouchSmart tm2 which is a tablet - it's like a normal laptop but the screen turns and folds to make it a tablet. 192.150.181.62 (talk) 19:32, 29 September 2010 (UTC)

To make sure we're all on the same page: you know, I take it, that your computer came with a digital pen and an application that allows you to write handwritten notes and save them. (I haven't used one, but this is my understanding.) What you want is a better note-taking application. Is that correct? Looie496 (talk) 00:30, 30 September 2010 (UTC)

I might be missing the point here, but what's wrong with a notepad and pen? Both are considerably cheaper and lighter than a tablet PC, require no electricity, are resistant to rough handling, and very flexible for notetaking in university lectures. Astronaut (talk) 11:27, 30 September 2010 (UTC)

"Windows:Tablet Edition" is supposed to come with "Windows Journal" which does exactly what you describe. It's quite handy.

http://www.microsoft.com/windowsxp/using/tabletpc/russel_03january20.mspx APL (talk) 16:05, 30 September 2010 (UTC)

I couldn't find any application on my laptop to do this. Windows Journal is EXACTLY what I wanted, thank you, it's not in the list of all programs in Start Menu oddly, but I searched it and it came up. Thank you so much. THe problem with a notepad an pen is that I lose all my notes, and they're ont organised or anything,cwhereas this does it all, and the notes can be duplicated and transmitted in seconds. Thanks again! 192.150.181.62 (talk) 20:48, 30 September 2010 (UTC)

computer

what is the name of the first computer used? —Preceding unsigned comment added by 199.93.81.1 (talk) 22:57, 29 September 2010 (UTC)

Not the easiest question to answer, for it depends on your definition of computer. History of computing explains the difficulties, and would probably answer "a piece of string with 12 knots". History of computing hardware takes you through the various epochs of hardware development. But I suspect something like the table in ENIAC is probably what you're after. --Tagishsimon (talk) 23:18, 29 September 2010 (UTC)

"The first working von Neumann machine was the Manchester "Baby" or Small-Scale Experimental Machine, developed by Frederic C. Williams and Tom Kilburn at the University of Manchester in 1948" according to the article linked above. 92.29.120.195 (talk) 19:45, 30 September 2010 (UTC)

On a related note, what was the hostname of the first computer where that parameter would have been relevant? I'm guessing it would have been an early private network, and I'd bet that the hostnames were "terminal" and "computer," respectively... but can't find this in our history of the internet or related articles. Nimur (talk) 09:52, 30 September 2010 (UTC)

Networking and server-host systems existed before ARPANet/Internet. So, it would precede the history of the Internet. If you are specifically looking for Internet usage, I'd check with Iowa State University because I figure they had one of the first computers on the network. -- kainaw™ 13:32, 30 September 2010 (UTC)

Used how? The first modern computer (to be publicly known) is considered to be the Z3 completed in 1941.Smallman12q (talk) 22:14, 1 October 2010 (UTC)

What regulatory issues have to be considered when exporting or building products that heavily use cryptography?

What federal laws do you have to be aware of when implementing software that incorporates cryptographic protocols? This question is for the US as well as internationally. Procrastinatus (talk) 23:48, 29 September 2010 (UTC)

Our article section Cryptography#Legal issues and our article Export of cryptography in the United States have some information that will be useful. Unfortunately our general article Export of cryptography is a stub. Comet Tuttle (talk) 23:54, 29 September 2010 (UTC)

The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

---

None if you do it anonymously. ¦ Reisio (talk) 04:58, 30 September 2010 (UTC)

This is false. Just because you don't put your name on something doesn't mean it can't be traced back to you, and certainly doesn't mean you can ignore legal requirements. "Do it illegally" is both bad legal advice, and bad advice anyway. --Mr.98 (talk) 13:00, 30 September 2010 (UTC)

If it can be traced back to you, you didn't do it anonymously. Doing things in accordance with laws (that apply to you or do not) won't keep you out of trouble, either. The only way to be sure is to be anonymous. Also, I'll thank you to leave my comments alone. ¦ Reisio (talk) 04:37, 1 October 2010 (UTC)

We strike on the Reference Desk when really bad advice is being given. This is not article space and it is not talk space. Anyway, "do it illegally, but don't get caught" is both legal advice and bad advice. If you disagree with my striking it out, please feel free to complain on the talk page, but I think you'll find you're in the minority on this one.--Mr.98 (talk) 02:14, 3 October 2010 (UTC)

Not that you seem to care at all, but see second paragraph. ¦ Reisio (talk) 18:45, 3 October 2010 (UTC)

Note that the Reference desk is not supposed to give legal advice.—Emil J. 10:23, 30 September 2010 (UTC)

So far I have only seen one instance of "legal advice" above (which I removed; it was not informed, anyway, just suggesting that they "do it anonymously" and could therefore ignore the law, so there is no loss) — the rest is just pointing in a general direction towards resources for further information, which is completely valid. --Mr.98 (talk) 11:29, 30 September 2010 (UTC)

I would get in touch with the Electronic Freedom Foundationif you want a really comprehensive and probably accurate answer that has real legal analysis behind it. --Mr.98 (talk) 11:29, 30 September 2010 (UTC)

The discussion above is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.

September 30

Hack firefox to reenable saving passwords

My Firefox has password saving disabled; how can I reenable it? Do I edit something in about:config? The Hero of This Nation (talk) 12:54, 30 September 2010 (UTC)

• On Windows, I think you just need to check the box at Tools -> Options -> Security -> Remember passwords for sites. --59.95.97.116 (talk) 14:20, 30 September 2010 (UTC)

• Sorry for not being more clear in my initial question, but that option is disabled in my Firefox options. Meaning greyed out, can't click it. I am in Firefox 3.6.6 for Windows. The Hero of This Nation (talk) 15:46, 30 September 2010 (UTC)

I don't know why it has been disabled, but perhaps going to about:config and setting signon.rememberSignons to true will do the trick? --Sean 16:48, 30 September 2010 (UTC)

Protocol for electrical signals going from computer to monitor.

What is the protocol for the graphical information about what to put on the screen at the very lowest level where the electrical signals are going through the wire to the monitor? This must be a standard since I can connect a different manufacturer's monitor to my computer and still have it work. Thanks. 20.137.18.50 (talk) 13:39, 30 September 2010 (UTC)

Much of this is specified, or at least standardised, by VESA; see the articles linked from there, and from Computer display standard. See also the VGA connector article. -- Finlay McWalter ☻ Talk 13:48, 30 September 2010 (UTC)

Eskimo Question

what is the differnces between the eskimo and aboriginal people and why? i need every detail please and thank you —Preceding unsigned comment added by 68.179.16.89 (talk) 14:53, 30 September 2010 (UTC)

"Aboriginal" is a general word that can refer to any indigenous people. (Australian Aboriginals, Native Americans, Eskimos, etc.)

"Eskimo" is more specific. It refers mostly just to Yupik and Inuit people.

(Incidentally, if you know which group of people you're talking about, nowadays it's often considered more polite to say "Yupik" or "Inuit".) APL (talk) 15:57, 30 September 2010 (UTC)

I think this should be in the Humanities reference desk. And the difference is that they live in different areas of the worldSir Stupidity (talk) 07:51, 1 October 2010 (UTC)

http status codes

I need a program for Windows that can monitor many urls http status code ever 10 mins or so. Similar to this site http://www.404checker.com/404-checker but offline version —Preceding unsigned comment added by 174.139.74.140 (talk) 18:07, 30 September 2010 (UTC)

This is probably something cURL could do, if you put it in a shell script.--el Aprel (^facta-_facienda) 20:08, 30 September 2010 (UTC)

I would strongly suggest that you learn a programming language for this kind of thing (one of the widely used "scripting languages"—Python is probably a good choice). Then you can (for example) do a Google search for "python http", which turns up this page, at the bottom of which is this example:

     >>> import httplib
     >>> conn = httplib.HTTPConnection("www.python.org")
     >>> conn.request("HEAD","/index.html")
     >>> res = conn.getresponse()
     >>> print res.status, res.reason
     200 OK

Once you know the basics of Python programming, you can easily turn this into a script that will loop over many pages, repeat every ten minutes and do whatever you want with the status codes. The entire process will probably take less time than you would need to read the documentation for curl's many command-line options. The up-front cost of learning Python will repay itself unless you never expect to need to do a task like this again. -- BenRG (talk) 21:05, 30 September 2010 (UTC)

Well said, BenRG. The exact purpose of a high-level scripting language, like Python, is to allow a power user to define a complex custom task, like "repeat this operation every 2 minutes." The OP should not be intimidated by the learning curve - scripting is easy and straightforward (and does not require as much sophisticated formal training as general purpose computer programming). Besides, as BenRG has pointed out, any specialized program that could provide the level of customizability that the OP has requested would essentially be a scripting language; so it would really serve the OP best to choose a general purpose tool so the learned skills are re-usable. Python has the advantages of being platform-portable, generally "easy to read", and has an enormous user base, so it is easy to find information on the web or ask for help. Other good languages to know are perl, bash scripting, and PHP; all are capable of accomplishing the same tasks, but each has unique capabilities targeted at solving particular styles of problems. Nimur (talk) 22:49, 30 September 2010 (UTC)

MS Zone.com online games in WinXP

Zone.com is part of Microsoft. I often play these games using the Programs/Games/ menu in WinXP. No logging on or user name is required, an anonymous nameless opponent is rapidly found and you play.

How do these games link up with others? What is the protocol used? I often play these games, including just a few seconds ago, so the information from Microsoft saying that they were retired in 2006 cannot be true, or must refer to something else. Nor am I using as far as I know a Live Messenger version of the games, as I do not need any user name etc. Thanks 92.29.120.195 (talk) 20:16, 30 September 2010 (UTC)

Some are Flash, some are Java applets, some appear to be Active X. Each of these can open their own connections back to the server from which they came; to minimise problems with firewalls etc. they probably do that over HTTP. -- Finlay McWalter ☻ Talk 21:53, 30 September 2010 (UTC)

These games probably use the Internet Games Core component.Smallman12q (talk) 01:04, 1 October 2010 (UTC)

This http://forums.techarena.in/windows-xp-games/752409.htm seems to relate to what I use, I think. I do not understand it. I ask because in recent weeks when I try to have a game there has often been no responce from the server, according to an error message. I've been wondering if the protocol is something to do with Windows Messenger. The current version of Windows Messenger is fourteen, but my installed version is only version four. I do not like Messenger and do not want any more annoying spam pop-ups, but if I updated Messenger would it reduce the proportion of times I get no responce from the server? 92.28.254.154 (talk) 21:27, 2 October 2010 (UTC)

Who physically made the first Apple Computers

I mean who physically made them once the number of orders exceeded what Steve Wozniak could do by hand? 76.27.175.80 (talk) 21:10, 30 September 2010 (UTC)

I suppose you're looking for the manufacturer of the Apple II, But the original Apple I kits were assembled by Steve Jobs, Steve Wozniak, and Ronald Wayne. (I'm pretty sure Wozniak was doing the difficult technical work. ) They only sold about about two hundred of them in over a year, so it wouldn't surprise me if they didn't need outside help.APL (talk) 21:55, 30 September 2010 (UTC)

Please see our Apple I article for more info. There are a few references there on this issue. Hope it helps. - 220.101 talk^\Contribs 04:24, 1 October 2010 (UTC)

From woz.org/letters/general/13.html, "WOZ:First, the Apple I (and Apple ][) computers were entirely designed and tested and debugged in my Cupertino apartment (not the garage) and in my cubicle at Hewlett Packard in Cupertino (that 'calculator' division is now in Corvallis, Oregon). The PC boards of the Apple I were made in Santa Clara. As soon as they came off the production line (only 200 total were manufactured) components and chip sockets were inserted by workers and the board were wave soldered there. This was the major manufacturing step. We'd drive down and pick up a batch of boards and then drive them to the garage. We'd pay Patti Jobs and other friends $1 per board to insert all the chips from boxes of chips that we had. The garage had a single engineering workbench with a mylar top and a shelf. A monitor and transformers and keyboard, the other 3 pieces of an Apple I, were on it, as well as an oscilloscope of mine and maybe a soldering iron. I'd hook up a PC board and try it out. If it seemed to work, it would go in the 'good' stack. If it was bad I'd look at the microprocessor data and address pins with the oscilloscope. If I saw a missing signal it meant that a chip had a pin out of a socket. If a signal seemed like two fighting signals (halfway between high and low) it meant that two traces were shorted on the PC board. About half of the boards had such problems. " So it was another company who physically made the boards and soldered the sockets in, then Jobs's sister Patti and some others did the remaining physical work. 20.137.18.50 (talk) 13:50, 1 October 2010 (UTC)

October 1

Long delay after first right click

The first time I right click something after initial booting up, the big hour glass comes up and it takes a looooong time for the menu to drop down--as much as 3 minutes. After that first right click everything is back to normal; the menu drops down immediately. What causes this delay?

I use XP.

Thanks,

Norm Strong —Preceding unsigned comment added by 71.231.141.223 (talk) 04:03, 1 October 2010 (UTC)

If it's the first right-click on the desktop or a file-explorer window, then I'd suspect a Shell Extension is being loaded. These are programs that add items to the context (right-click) menu of explorer. Explorer also provides the desktop (and the taskbar). However, I'm not sure about that best way to temporarily disabling an program from the menu, to help track down what is causing it. Have you installed a program recently? —Preceding unsigned comment added by Csmiller (talk • contribs) 06:05, 1 October 2010 (UTC)

I would be cautious; it could be malware infecting a shell extension, and was probably installed recently. Run virus scans, check for malware with a malwate scanner like Malwarebytes' Anti-Malware and maybe run Autoruns to check what is loaded at startup. Astronaut (talk) 07:22, 1 October 2010 (UTC)

I have seen this happen due to bad drive mappings causing all sorts of incredible slowness including when using the rightclick menu anywhere in the system. If you have any drives mapped try removing them and see if it speeds up. The other big culprit I have had do this is WinZip (or similar file archive tools) that use shell extensions for all files; if the program is misbehaving (not uncommon for WinZip) it can cause slowness. I once had it fail so bad that every right click caused the WinZip installer to try to start up, which took a fair bit of time and eventually exited with an error message. I had to manually delete all the references from the hard drive and registry before it would go away. Now, I use 7-zip and while slower to do file operations the shell integration works without issue. --144.191.148.3 (talk) 14:41, 1 October 2010 (UTC)

Spanish Accents

Right, this is going to be a tester. To get Spanish accents I usually hold down Ctrl and Alt at the the time, and while holding them I press the vowel of my choice. That results in á, é, í, ó and ú. I get ñ by holding down Alt and typing 0241 on the number pad. That's all well and good when I'm using a QWERTY keyboard and Windows. I'm in France at the moment and am using an AZERTY keyboard and Ubuntu. The Ctrl + Alt method doesn't work and nor does Ctrl + 0241. Does any one have any idea - except for cutting and pasting - how to get these accents? — Fly by Night (talk) 08:01, 1 October 2010 (UTC)

See our Compose key page. Basically, press Shift+AltGr (press AltGr last, release first), release both keys, press and release ', press and release the vowel. CS Miller (talk) 08:06, 1 October 2010 (UTC)

I've just tried that and I got 'e as the output. I did the following:

• Press and hold Shift
• Press and hold Alt Gr
• Release Alt Gr
• Release Shift
• Press '
• Press e

Are you sure it works on Ubuntu? — Fly by Night (talk) 08:18, 1 October 2010 (UTC)

Odd. It works for QWERTY keyboards on Ubuntu, but not on AZERTY. Apologies. CS Miller (talk) 08:37, 1 October 2010 (UTC)

Add a keyboard layout (System --> Preferences --> Keyboard --> Layouts --> Add). Then click on Layout Options --> Layout switching to create a keyboard shortcut for changing layouts. This is also the better way to type Spanish words in Windows, by the way. In Windows, I created keyboard shortcuts for switching to Spanish, Greek, and Russian keyboards by going to Start --> Control Panel --> Regional and Language Options --> Languages -> Details... --> Add.... The semicolon key types an N with a tilde. The left-bracket key adds an accute accent to any vowel you type afterward.--Best Dog Ever (talk) 08:32, 1 October 2010 (UTC)

Great, thanks for that! — Fly by Night (talk) 09:13, 1 October 2010 (UTC)

If you use an international layout, you can use dead keys, which is going to be the least painful way (no layout switching required). ¦ Reisio (talk) 18:49, 3 October 2010 (UTC)

I always use charmap instead of key combinations. Comet Tuttle (talk) 16:29, 1 October 2010 (UTC)

But Ubuntu is a Linux based operating system and doesn't have anything to do with MS Windows. — Fly by Night (talk) 19:59, 1 October 2010 (UTC)

in Ubuntu, hold alt gr, then press #. Release both keys then press a. Do you get à? For me, ñ is alt gr and ], then n, and I can get most accented characters simlarly. 129.67.37.143 (talk) 22:36, 1 October 2010 (UTC)

Recursively Search a Directory to Find and Replace Contents of Files Using the Command Line

I'm trying to write a small shell script on OS X that will recursively search through a directory and replace all the instances of 'foo' in files with 'bar'. I assume that grep and sed are the best way to do this, but I can't quite figure out the syntax to make them work together.

Thanks for any help. --CGPGrey (talk) 08:20, 1 October 2010 (UTC)

grep -rl foo . | xargs sed -i backup s/foo/bar/

This will also create backups of the files it modifies (the original filename, plus a .backup extension) —Obeattie (talk) 12:42, 1 October 2010 (UTC)

Thanks for that, unfortunately, I'm on OS X, which does not allow the use of the -i switch. Is there another way? --CGPGrey (talk) 13:10, 1 October 2010 (UTC)

I too am on OS X, which seems to allow -i, I just tried it. What OS version are you using? —Obeattie (talk) 13:16, 1 October 2010 (UTC)

Perhaps you have installed the GNU utilities? This page says GNU sed supports -i but that the BSD one that ships with OS-X does not. -- Finlay McWalter ☻ Talk 13:27, 1 October 2010 (UTC)

Anyway, this isn't quite so nice, but it can be done faily easily just using a for loop. This removes the dependency on the -i flag:

for f in $(grep -rl foo .); do mv $f $f.backup; sed s/foo/bar/ $f.backup >| $f; done

—Obeattie (talk) 13:24, 1 October 2010 (UTC)

This looks to be getting me the closest, but I'm getting a ton of 'no such file or directory' errors when I run it and it produces lots of empty files in the directory that I run it from. Perhaps it's because I have spaces in the names of my folders and files? --CGPGrey (talk) 15:05, 1 October 2010 (UTC)

Yes, that's the reason. I would respectfully suggest that if you are planning to perform more scripting jobs like this, you rethink the naming conventions of your files so that they do not involve spaces. As you can see, it is nothing but a constant source of headaches. You can try

grep -rl foo . | while read f; do mv "$f" "$f.backup"; sed s/foo/bar/ "$f.backup" > "$f"; done

(inspired by Tardis' answer to your previous question).—Emil J. 16:08, 1 October 2010 (UTC)

Actually, there is one more subtle problem: all the sed commands above will fail to work properly if there are more occurrences of foo on the same line. You should use sed s/foo/bar/g.—Emil J. 16:25, 1 October 2010 (UTC)

(e/c) This suggests an explicit -e might fix it: sed -i backup -e s/foo/bar.—Emil J. 13:26, 1 October 2010 (UTC)

I find it preferable to just backup the whole directory tree, rather than individual files. Then you don't have to write another script to restore things back to the way they were. --Sean 14:22, 1 October 2010 (UTC)

"A programmer had a problem and decided to work on it by using regular expressions. Then the programmer had two problems." Comet Tuttle (talk) 18:57, 1 October 2010 (UTC)

Regular expressions are the crack of programming. Shadowjams (talk) 20:21, 2 October 2010 (UTC)

Avoiding Javascript timeouts.

I have a complicated JavaScript program and in Firefox, I get a popup that says: "A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete." I know you can have users set: dom.max_script_run_time to make this timeout longer - but this is for general use. I'm putting a 'progress meter' into the script so people can tell when it's going to finish.

Does anyone know what criteria Firefox is using to calculate this timeout? Is there something I could do in my script to reset the timer periodically? (eg Is it enough to stop running - but with a timerevent set that would set things running again a few milliseconds later?) 70.112.128.105 (talk) 17:37, 1 October 2010 (UTC)

Every so often (say every N loops around your main loop) you a) schedule a timer event (setTimeout) to call yourself, and then b) call yield() -- Finlay McWalter ☻ Talk 17:45, 1 October 2010 (UTC)

To phrase it another way: Redesign your algorithm so it does a little work and then goes to sleep. Put the work done in a function. If the function finishes and there is more work to do, use the setTimeout to call the function again. This way, the web browser will see each function call as a separate script running and not one never-ending script. -- kainaw™ 19:22, 1 October 2010 (UTC)

Actually you don't need (js1.7) keyword (my bad, not a function) yield; you just store state in a global variable and return. Here's a simple example that calculates fibonacci numbers without jamming the processor for too long. The key is that it only goes through its main loop itercount times before yielding back to the main event loop (in practice itercount would be a much larger value, probably tens or hundreds of thousands).

javascript source

function main(){ var n = 49; console.log("looking for fib(" +n+")..."); get_fib(n); } var FIB_GLOBALS={}; // a single global to store our persistent state // action to take once the calculation is complete function report_fib(n){ console.log("the fib you asked for is ", n); } function get_fib(n){ if (n==0 || n==1) report_fib(0); else if(n==2) report_fib(1); else { FIB_GLOBALS.alpha=1; FIB_GLOBALS.beta=1; FIB_GLOBALS.count=n-2; calc_fib(); } } function calc_fib(){ var itercount = 3; // absurdly small value for demo purposes while (itercount-- > 0) { total = FIB_GLOBALS.alpha + FIB_GLOBALS.beta; if (--FIB_GLOBALS.count==0) { report_fib(total); return; // success } FIB_GLOBALS.alpha = FIB_GLOBALS.beta; FIB_GLOBALS.beta = total; } setTimeout(calc_fib,0); // yield }

This is a slightly poor example, as we overflow ints long before running into the timeout problem. Can someone think of a very simple algorithm that we can use instead of fib(), that will take a modern computer a few tens of seconds to do, and that won't require bignums or too much code? -- Finlay McWalter ☻ Talk 19:48, 1 October 2010 (UTC)

Thanks! I get the idea. 70.112.128.105 (talk) 00:32, 2 October 2010 (UTC)

VLOOKUP in Excel

I'm working with Excel 2007 (on Windows Server 2003, if that matters...). I'm performing a series of VLOOKUP functions using a formula like this: =VLOOKUP($A3,mattd!$A:$U,16,FALSE) Nothing too unusual there and it works just fine as it's written. What I would like to do is, instead of typing in "mattd" there (the title of one of the worksheets), I'd prefer to lookup that name in a cell. For example, if cell A1 was "mattd" =VLOOKUP($A3,A1!$A:$U,16,FALSE) would lookup the relevant data on the mattd worksheet and if cell A1 was "barts", that same formula would look up the relevant data on the barts worksheet. When I do that, though, Excel is not expecting it and opens a search for another file to look in. Is there a way I can make Excel read the text of a cell and treat it as part of a formula in this way? Matt Deres (talk) 18:10, 1 October 2010 (UTC)

You need the INDIRECT function: VLOOKUP($A3,INDIRECT(A1&"!$A:$U"),16,FALSE), or with A$1 if you intend to copy the formula down the sheet. Bear in mind that as this is an indirect reference, the link will break if you move the lookup table away from the $A:$U range. AspidistraBaby (talk) 19:19, 1 October 2010 (UTC)

Great! That's exactly what I need. Thanks very much! Matt Deres (talk) 20:10, 1 October 2010 (UTC)

Third and fourth hardware questions

This question is slightly related to the two questions I asked above. I switched from the Asus motherboard that I planned to purchase to this one from ASRock. The only problem is that the computer has two PATA/IDE devices -- a hard drive and CD/DVD drive -- and only one port. Yet everything I've read said the one port supports two devices, but nowhere can I find something that tells me how I can plug two devices into the one port. Any suggestions? I thought of ignoring this and buying a $10 IDE-to-SATA bridge. If I did that, would I need to buy an extra length of SATA cable? Please excuse my n00biness, Xenon54 (talk) 23:41, 1 October 2010 (UTC)

All PATA ports support two PATA devices. Make sure you get a PATA cable with three connectors (one for motherboard, one each for the two devices). Typically you use jumpers on the devices to designate one "master" and one "slave" (you can often just use cable select, but some older devices don't do this properly). Plug em in, power up, make the BIOS search for them, then you'd done. -- Finlay McWalter ☻ Talk 23:49, 1 October 2010 (UTC)

October 2

GIS for Newbies

Can someone explain how GIS works in a much simpler way than the article? I find the lead is rather nonspecific whereas the remaining body is overly inaccessible to someone with no knowledge on the topic, at least in my personal opinion. Is it a computer program that stores data based on coordinates or locations on the map? I am not really sure. Are there any good non-Wikipedia websites that offer an intro to what GIS is? Thanks. --128.54.231.9 (talk) 09:06, 2 October 2010 (UTC)

GIS is a field of study. It covers the maths for describing (and converting) geographical locations and relationships, the data formats to store geographical info, and the software to process, change, render, and edit geographical information. -- Finlay McWalter ☻ Talk 10:58, 2 October 2010 (UTC)

Any authoritative, yet simpler introduction to the subject other than wikipedia? --128.54.231.9 (talk) 05:46, 3 October 2010 (UTC)

There's this book, which I haven't read, but which gets a couple of decent customer reviews. I have no idea whether it's simpler than our article. Even if you don't buy the book, the publisher's description might be of interest, as it gives an overview of the subject. --NorwegianBlue ^talk 12:26, 3 October 2010 (UTC)

Uninterruptible power supply

Resolved

I want to build a UPS. I have an old car battery, would that in combination with a dc-ac inverter be enough to power one desktop computer with lcd screen? How long would it run for? 82.44.55.25 (talk) 16:16, 2 October 2010 (UTC)

Car batteries are not designed to be deeply discharged, or to remain discharged for any length of time because this shortens their life. It would be better to keep you car battery charged with a charger that supplies power at about the same rate as your computer uses it, and rely on the battery only when the mains supply fails. (This is how a purpose-built UPS works, with a circuit that cuts the charging to a trickle when no current is being drawn.) Your dc-ac inverter uses switch-mode circuitry, and there can sometimes be a problem when this is connected to another switch-mode power supply in your computer. My laptop goes "haywire" when I try this, but your desktop might be OK if you have a good quality inverter. Dbfirs 16:49, 2 October 2010 (UTC)

How long would a standard car battery be able to run a desktop computer with lcd screen for? 82.44.55.25 (talk) 10:10, 3 October 2010 (UTC)

A typical car battery holds about 80 ampere-hours, that's less than a kilowatt-hour. The time that it would run your computer for depends on the power requirement of your computer and monitor, but for example, perhaps three hours at 300 watts consumption. As a car battery ages, its capacity reduces, so you might only get two hours out of a used battery. Dbfirs 17:08, 3 October 2010 (UTC)

Thanks :) 82.44.55.25 (talk) 17:11, 3 October 2010 (UTC)

Under intensive use (CD writing etc), a computer might draw up to 400 watts, so perhaps not even two hours with the monitor as well. Dbfirs 17:13, 3 October 2010 (UTC)

I fear it's much worse than that. That 400W is the DC output of the PSU, but the PSU isn't very efficient. Power supply unit (computer)#Energy efficiency puts it at 75% or so; so to supply 400W you'd need to consume ~540W on the AC end. When running off the battery, that 540W has to be supplied by the inverter, which itself isn't going to be perfectly efficient. If we handwave that at 75% efficiency also, that means you'd be drawing 720W off the battery to give the computer's components 400W; that virtually halves the time estimate. But 720W into 12v is a discharge of 60A; can an ordinary lead-acid battery safely and successfully discharge at 60A for a prolonged period? -- Finlay McWalter ☻ Talk 17:34, 3 October 2010 (UTC)

That's true, though I think you are putting forward the worst case. Some power supplies can be up to 94% efficient according to the same article. One must also factor in to the argument that it is rare for a normal home computer doing regular tasks to draw 400 watts. As little as 100 watts might be more realistic for some models in light use. I agree that a single car battery would struggle to sustain a 60 amp supply for very long, and perhaps several batteries in parallel might be needed. There is also the possible problem caused by putting two switch-mode transformers in series. It creates havoc with my laptop, but that might just be the fault of its cheap power supply or my cheap DC to AC inverter. (I would need an oscilloscope to see what was really happening.) Dbfirs 19:45, 3 October 2010 (UTC)

Yes, indeed. A practical concern remains regarding what one does with the time the UPS gives. Particularly for servers, given their high draw and the rubbish performance of UPSes (which mostly have rather expensive lead-acid batteries in them) it's only wise to use the UPS to bridge only small outages, and to use the rest of the leeway it grants for an ordered shutdown. The trouble is that shutdown wakes all the processes up (by sending them a SIGTERM) and they all get to do some disk activity, and the cache swap thrashes terribly, and only then the disks be synced and the system stopped - all the very opposite of the conservative power-sipping one wants when power is scarce. I used to have a modest server (dual-core Xeon, 6 disk raid, redundant PSU) running off a UPS which had a little indicator that showed the expected uptime at the current draw; it usually hovered at around 20 minutes. But when the power failed and the UPS told the server, the server started shutdown, and that 20 minute estimate plummeted to about 5 (which, as the batteries aged, fell such that the server barely got down in time). The worst-case scenario (yes, I like those) was the dreaded kangaroo-start, where some electrician somewhere was woggling the power on and off every few minutes. The server would shutdown, then restart, then down, etc. - but it took about 2 minutes in the achingly slow BIOS and OS load before it started the apcupsd (which, given the power was back off, told it to shut back down again). So each cycle chewed through maybe 4 minutes of UPS at full drain. TL;DR: batteries suck. -- Finlay McWalter ☻ Talk 20:13, 3 October 2010 (UTC)

For a server and several hard drives, I agree that one wouldn't get much use out of an old car battery. If the OP wants to use a computer for a significant time without mains power, then several batteries in parallel might be advisable. Finlay's comments on efficiency prompt me to wonder whether it would not be better to supply direct 12v and 5v supplies to the equipment from separate batteries. Are there any UPS units that do this? Dbfirs 08:10, 4 October 2010 (UTC)

DC power is common in telecoms back-office equipment, and are sometimes used for server applications, but I'm not aware that they're available for consumer/soho grade equipment. The very few places where people really care about workstation uptime (I guess military and emergency-response) rely on generators. There's some mention at Uninterruptible power_supply#DC power -- Finlay McWalter ☻ Talk 10:39, 4 October 2010 (UTC)

comments on efficiency prompt me to wonder whether it would not be better to supply direct 12v and 5v supplies... To improve the efficiency, look at a DC-to-DC converter. This should be more efficient than using an inverter to raise 12V to AC line voltage and then the PC's power supply to reduce down again. A linear type won't be too effective here since the voltage drop is large expressed as a ratio of input (12V) with the output probably being 5V or lower. The difference in voltage is essentially lost as heat. A switching type with DC input and output might work well though, the efficiency can be >75%. You'd need one with multiple outputs to match the inputs on your PC motherboard - or else use one DC-DC switching converter to an intermediate required voltage - say 5V and then linear converters to go from 5v to any lower voltages required by components -e.g. 3.3V. See DC-to-DC_converter. CDROM drives and hard disks might require 12V for the spindle motors - so just a linear converter for those taken off the battery direct - typically a car battery will provide something like 12.8V. 92.236.82.86 (talk) 22:28, 4 October 2010 (UTC)

Odds

what are the odds of matching any 3 cards drawn from a deck of 52 playing cards with a single card drawn from a separate deck of 52 playing cards —Preceding unsigned comment added by 70.68.31.151 (talk) 17:34, 2 October 2010 (UTC)

There are 52 possible cards and 3 of them have the possibility of matching the original 3. So, 3 in 52 is your odds of getting one of those cards out of the deck of 52. -- kainaw™ 18:29, 2 October 2010 (UTC)

... though, being pedantic, 3/52 is the probability (which was probably what was being asked!) The "odds" are 49 to 3 against. Dbfirs 19:36, 2 October 2010 (UTC)

actually, that's not correct. drawing three cards is drawing without replacement, so your odds probability is 1/52 + 1/51 + 1/50 or .058839 (not the .057692 that 3/52 would suggest). Or so it seems to me... --Ludwigs2 04:50, 3 October 2010 (UTC)

No, Kainaw was right. That second term of 1/51 only applies when there was no match on the first card, so it needs to be multiplied by the probability of that, which is 51/52, giving 1/52. Similarly 1/50 needs to be multiplied by 50/51 and 51/52, again giving 1/52, so this method also produces a probability of 3/52. By the way, the RD/Math#Math desk would have been a better place for this question. --Anonymous, 05:06 UTC, October 3, 2010.

Ah, you're right (on both counts, actually). fair enough. --Ludwigs2 06:41, 3 October 2010 (UTC)

Mac database interface

I'm going to be putting together a rather simple document database, with a fairly small (e.g. probably less than a thousand records) dataset, for a rather elderly person soon, one that runs on a Mac. I haven't looked at the commercial-off-the-shelf database software lately, and wondered if anyone had any opinions as to what would be a good fit.

Requirements:

• Runs on a Mac.
• Pretty straightforward interface for a non-tech savvy person. (Note that I am tech savvy, so it doesn't have to be dumbed down to set up. It just needs to allow me to make a GUI for navigating the data that will be simple for this rather elderly person.)
• Needs to be able to handle PDFs natively. How this might work probably will depend on what is out there. Ideally it'd be nice if they could be viewed from within the database, but if they were externally linked (so they'd open up with Adobe Reader or something), that might be fine.

Free is nice but not required. I could of course labor to create something in MySQL/PHP and then install a MAMP on this guy's machine... but that's probably the most labor-intensive solution and it'd be nice to not have to re-invent the wheel. And it would also make it harder for future people to use, as they'd have set up the MAMP, which is just an extra pain in the neck I'd love to avoid.

Any thoughts? I have not played with OO.org Base for a long time but when I did the interface was clunky and it was pretty slow. I've been thinking about Bento but I've never used it and can't seem to find anything about its PDF capabilities (though I see it has a trial period, so maybe I'll give that a shot first). In a fix, bibliographic software like EndNote might work, though my past experience with them was that they were a pain to use and more complicated than I'd want this to be, but again it has been awhile. Any thoughts? --Mr.98 (talk) 17:35, 2 October 2010 (UTC)

If document management specifically is your goal, perhaps a document management system would be more appropriate than a naked database. I haven't personally used it (but then the for-money DMSes that I have used have been fairly unimpressive) but perhaps OpenKM will meet your goals. It will index a variety of documents, including PDFs. -- Finlay McWalter ☻ Talk 17:40, 2 October 2010 (UTC)

I haven't really looked at DMSes, I'll definitely check them out. Thanks. It looks like the OpenKMS GUI is a bit too scary for my target audience (this guy is not tech savvy), but maybe DMSes in general are a fruitful thing to investigate. --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

Can you give more details about the way this database will be used (e.g., what are the kinds of data that need to be entered, how complex are the operations that need to be run on it, does it need to act as a server or is it a simple one-client db...?). A combination of Spotlight, metadata keys and smart folders can satisfy most simple file-oriented database requirements with minimal effort and an intuitive GUI. --Ludwigs2 18:29, 2 October 2010 (UTC)

FileMaker is popular with Mac users because of its ease of use.--Best Dog Ever (talk) 19:07, 2 October 2010 (UTC)

For mac, FileMaker is most likely what you're after as their isn't a mac version of Microsoft Access.Smallman12q (talk) 00:51, 3 October 2010 (UTC)

All of the FileMaker databases I've looked at in the past are basically big card file stacks. I find that kind of hard to deal with as an interface, personally, being more or less limited to looking at one piece of data at a time. Access is too far on the "pain in the neck" side of things even if it did have a Mac version. (Hence OO.org Base isn't really very appealing to me.) I say this as a very long-time Access programmer. :-) --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

What I'm imagining is a pretty easy database scheme — titles, dates, authors, keywords, some notes, etc. And of course the documents themselves. The whole thing has to be pretty easily searchable. It'd be nice if the interface was something like a search box that then gave you a list of matching records, which could then be clicked on for the information about the record, and a link to the document itself. Pretty basic stuff. One could again whip it up with MySQL/PHP, but only with a great investment of time... It's a very simple model, nothing fancy, nothing even relational. What I'm looking for is more something that will allow me to make something with an easy-yet-powerful interface (not just searching through a stack) with a minimal amount of effort/time investment in setting it up. --Mr.98 (talk) 01:56, 3 October 2010 (UTC)

again, most of this is covered by Spotlight metadata - for instance, I can open a find window in the Finder and search for all PDF documents whose author is X and whose title contains Y, use Quicklook to choose the correct one, open it in Preview for viewing or to make annotations and add spotlight keywords. I can't really see why you need a relational database beyond what the system already offers you. You might need a metadata editor to fix pdf files that lack or have misinformation in their metadata if you're getting your pdfs from sketchy sources, but if you have well-formed files the system is already doing what you seem to want. --Ludwigs2 03:34, 3 October 2010 (UTC)

Spotlight is not a real database GUI. Trying to use it for anything complicated or systematic will not work. Plus you get the entire computer and not the specific dataset in question. Additionally, whenever a major OS change is made, the Spotlight interface and even method of operation can change. A filing system that is not predictably systematic is not an option. Anyway, thanks for the suggestion, but that's not going to work out for what I'm trying to use it for. --Mr.98 (talk) 14:04, 3 October 2010 (UTC)

Spotlight can easily be restricted to a single folder, and the underlying technology hasn't changed much at all since it's creation. Look, 98, I understand the resistance to using built-in technology (it seems somehow 'less than' and/or lacks a 'coolness' factor, plus there's that human irrationality where people will go out of their way to do unnecessary things because they don't feel like they've accomplished anything unless they've taken some kind of action), but if you're really trying to help this person then it behooves you to spend an hour looking into what's already there. spotlight is in fact a 'real' relational database system, deeply integrated into a 'real' graphical user interface (aka the Finder) and if it serves your needs you're not going to find anything easier to use or set up, not by half. Do as you like, but from the description you've given of the problem so far, I will (frankly) be surprised if you find anything as effective that doesn't involved extra costs, extra efforts and a noticeable learning curve. --Ludwigs2 16:17, 3 October 2010 (UTC)

Spotlight just doesn't seem like the right ticket for me. Let's just also point out that I might want this to be easily transferrable to other machines. I don't want to be having to go through and modifying everyone's Spotlight preferences every time they want to have a copy of the database. (I don't even want to modify *my* Spotlight preferences just so I can use this database!) And again, my experience with Spotlight so far is that depending on its identical functionality across OS versions is a very bad idea (it acts very differently between 10.4 and 10.6, I can say from experience). There's also zero possibility of setting up a custom interface or changing things if they aren't working the way I'd want them to. It's just not going to cut it for me for a variety of reasons, and frankly I don't think it's actually what it's good at. Spotlight isn't meant to be a customized database program; it's meant to be a filesystem searching program. I appreciate your help but it's just not what I'm looking for. I don't think you need to attribute my judgment on this to "human irrationality". I've been a database and UI designer for a looonggg time now and have a pretty good idea of what kinds of capabilities I would need such a system to have, and Spotlight (while it is very useful and clever) doesn't really have them. What I don't know is what the options are for off-the-shelf stuff... --Mr.98 (talk) 17:01, 3 October 2010 (UTC)

As I said, do as you like. but if this is what you're saying now then you clearly did not express the problem clearly above. why don't you start again from the top and explain in greater detail what it is you're trying to do. --Ludwigs2 17:10, 3 October 2010 (UTC)

Well, I didn't take into account every interpretation of my request, no, and I was fishing around for various ideas that I didn't want to artificially constrain by being overly picky from the beginning. I'm not unhappy with you for making the suggestion but I admit to some frustration at your absolute insistence of it being the One And Only Correct Choice and then criticizing me for not agreeing with you on it. --Mr.98 (talk) 20:58, 3 October 2010 (UTC)

It looks like what I'm looking for is really bibliographic/citation management software that is smarter than the stuff I have previously used. Something like Papers but not just tailored for use with scientific journals. (I've been playing with the trial download of Papers, and other than the fact that it has a lot of stuff that I don't need, and it is so rigidly insistent that everything I cite be a journal article, it works pretty well close to what I want in terms of interface.) Maybe EndNote, for all of its problems, is what I'm looking for in the end, since it does allow you a lot of flexibility in re-jiggering your fields. I'll fish around a bit along these lines as there do seem to be some options here. --Mr.98 (talk) 20:58, 3 October 2010 (UTC)

Mendeley's desktop client might do the trick; it's geared towards journal articles, but it's got an "other" category and a large set of fields. Paul (Stansifer) 20:49, 4 October 2010 (UTC)

noindex

Resolved

 – Ks0stm ^(T•C•G) 17:24, 3 October 2010 (UTC)

My facebook profile used to be within the top 10 for a search for my full name plus the City, State I live in. This concerned me greatly, so into my facebook profile I copied the text
<html> <head> <meta name="robots" content="noindex" /> <title>Don't index this page</title> </head>
hoping that it would remove my facebook profile from google searches. I did this quite some time ago (around 8 months to 1.5 years ago), and when I recently checked for it in search engines I couldn't find it. The only thing is that in the "page info" for my facebook profile url, the only robot orders it states are "noodp" and "noydir". Does one of these work in the same way as "noindex", or am I just lucky that my facebook profile isn't showing up in Google (I notice that other people with my same name's facebook profiles show up in google, but mine doesn't)? Ks0stm ^(T•C•G) 19:44, 2 October 2010 (UTC)

I don't know if Facebook sterilizes user profile content... I would guess they do... however you'd probably be better suited (even if your current approach works now) to change the privacy settings in Facebook itself. One of those allows you to not be listed in public search engines. There are other privacy settings you may be interested in as well. Shadowjams (talk) 20:18, 2 October 2010 (UTC)

Aha, found what you were talking about. This seems to explain why. Now, how do I get it to where I still don't show up in public searches once I turn 18 in a month? Ks0stm ^(T•C•G) 20:23, 2 October 2010 (UTC)

To make your Facebook account not show up on Google: Facebook > Account > Privacy Settings > Applications and Websites > Public Search > Edit Settings > Disable Public Search. They've hidden it good, no? --Mr.98 (talk) 02:07, 3 October 2010 (UTC)

Yeah, I never would have found that on my own. Thanks, that's pretty much all I needed. Ks0stm ^(T•C•G) 17:24, 3 October 2010 (UTC)

AppleMac 12" laptop, White

Resolved

 – Issue with extension settings

The above is running system 9 and the ability to 'drag and drop' has been lost. Any ideas as to how this might be restored please?--85.211.193.110 (talk) 21:08, 2 October 2010 (UTC)

What does it do when you try? I suspect it is a hardware problem (an issue with the mouse or trackpad) and not the operation system. Try hooking an external mouse up to it and seeing if that changes anything. The hardware must be ancient by computer standards if it is running 9. --Mr.98 (talk) 02:11, 3 October 2010 (UTC)

also, which generation Mac is it. a 12" white laptop is most likely an iBook g3 or ibook g4 - if the latter, you could upgrade it to Leopard Tiger relatively cheaply. in os 9 (If I remember correctly) drag and drop was added via a system extension - you could be seeing a corrupt extension or an extension conflict. have you added any new extensions or control panels recently, or added modules to existing extensions? --Ludwigs2 04:45, 3 October 2010 (UTC)

Yes it is an iBook, yes, it is, like me, OLD, but otherwise still useful. I don't use a mouse, just the trackpad. Nothing happens when I try to move an icon, it just stays put and don't move. I have not added any new extensions or control panels.--Artjo (talk) 06:42, 3 October 2010 (UTC)

You forgot to indent using colons. see wp:cheatsheet.

this is kind of hard to diagnose. if you can click on icons then it's probably not a mechanical problem, but you don't normally get random software failures - usually they happen just after you did something or changed something in the system (added a program, changed a setting, etc...). what were you doing just before this problem started happening? --Ludwigs2 06:47, 3 October 2010 (UTC)

Do you own a mouse your could try it with? The point is to try to figure out if there's something wrong with the touchpad (dragging will work with mouse.) or if a software setting has become screwed up somehow. (dragging won't work with mouse either.) APL (talk) 08:00, 3 October 2010 (UTC)

Problem SORTED. Fiddled with extension settings and all well now. Many thanks for your input, much appreciated. --Artjo (talk) 09:29, 3 October 2010 (UTC)

What controls this?

I have a desktop system at home, WinXP on a Dell box, and a similar system at the office, also WinXP but on a different Dellbox. From time to time I decide to clean the junk out of My Recent Documents, usually by exploring to C:\D&S\User\Recent and deleting away.

However, it's also possible to do this with popup menus, and here the two systems operate differently. I assume there's a configuration parameter that drives this, but don't have a clue what to call it or look for.

At Home	At Office
1) Click Start	Click Start
2) Hover to My Recent Documents	Hover to My Recent Documents
3) Slide to a document	Slide to a document
4) RIGHT-click	RIGHT-click
5) Popup menu appears	Popup menu appears
6) Click on Delete	Click on Delete
7) "Are You Sure" dialog appears; click OK	"Are You Sure" dialog appears; click OK
8) "Deleting" dialog appears, then closes	"Deleting" dialog appears, then closes
9) AYS closes	AYS closes
10) Start and Recent menus close	Start and Recent menus stay open
Begin at step 1 for the next file	Begin at step 3 for the next file

Naturally, the sequence of events where the Start menu does not close and needs not be renavigated is preferable. Anybody know what controls this behaviour, and how it can be configured on my home system?

Many Thanks, 97.116.127.118 (talk) 21:45, 2 October 2010 (UTC)

Hmmph. Failed to notice I wasn't logged in, sorry... DaHorsesMouth (talk) 21:49, 2 October 2010 (UTC)

For what it's worth, my XP system works like your "Home" configuration does. The first thing I would ask is the usually-difficult-to-answer question of what software differences, especially shell extensions, are installed on your home machine vs. your office machine. Comet Tuttle (talk) 16:40, 4 October 2010 (UTC)

October 3

vids

i need a program that will download vids from sites like metacafe ect. but will preserve the quality. i have the free firefox one but it only works on youtube ( i think)? —Preceding unsigned comment added by Kj650 (talk • contribs) 06:17, 3 October 2010 (UTC)

Stop thinking and know (and keep in mind that there are going to be some sites with videos/streams that you won't be able to easily download, despite it being wholly technically possible). ¦ Reisio (talk) 07:38, 4 October 2010 (UTC)

Try Flashgot. It works with most video sites. I just tried it with metacafe and it worked fine. APL (talk) 07:57, 3 October 2010 (UTC)

Looking up unicode character names from glyphs

I've just seen a series of peculiar glyphs used on a messageboard. Is there a site somewhere with an input box which I can paste a glyph into, which will tell me its unicode name so I can get some idea why it exists? Wurstgeist (talk) 13:11, 3 October 2010 (UTC)

http://www.fileformat.info/info/unicode/char/search.htm -- Finlay McWalter ☻ Talk 13:20, 3 October 2010 (UTC)

But it's worth just searching Wikipedia for it; there are articles for many of the commoner characters (e.g. 京). Failing that, search Google for "京 unicode" and you end up with pages like this. -- Finlay McWalter ☻ Talk 13:40, 3 October 2010 (UTC)

Thank you kindly. That didn't work for most of the characters (some of them turned into ordinary characters, some returned "not found") but it gave me the clue that what was going on was some heavy abuse of combining characters. Still not sure which ones. Probably all of them. :) 86.21.204.137 (talk) 13:44, 3 October 2010 (UTC)

Sometimes I've found myself pasting the mysterious characters into a python shell like this:

>>> u'天下の台所'

u'\u5929\u4e0b\u306e\u53f0\u6240'

So those characters are U+5929, U+4e0b, U+306e, U+53f0, U+6240, which we can then look up in the unicode character reference. -- Finlay McWalter ☻ Talk 14:26, 3 October 2010 (UTC)

I use this Firefox addon. Algebraist 14:29, 3 October 2010 (UTC)

Thanks - that's very useful. -- Finlay McWalter ☻ Talk 14:39, 3 October 2010 (UTC)

Yes, that did a really good job. COMBINING OGONEK (NON-SPACING OGONEK), COMBINING INVERTED BREVE BELOW (NON-SPACING INVERTED BREVE BELOW), COMBINING ALMOST EQUAL TO ABOVE, etc., etc. Wurstgeist (talk) 15:39, 3 October 2010 (UTC)

I wouldn't be surprised if you're talking about some strange smiley or something, but it's worth noting that if there's a mismatch between the input character set and the character encoding the page is being sent with, characters can render enitrely different from how the author may have intended them to. ¦ Reisio (talk) 18:54, 3 October 2010 (UTC)

It looks like this question has already been answered, but for future reference, when I want to look up a single Unicode character I've found unicode-search.net to be helpful. —Bkell (talk) 14:35, 4 October 2010 (UTC)

Hard drive

Resolved

I have lots of internal hard drives, some with Serial ATA and some with Parallel ATA connections. Some also differ in size and physical shape. I want to use them without opening up my computer and restarting it each time. I looked into hard drive enclosures and docking stations but it seems as though there's no "all in one" solution that will work with all my drives, and I don't want 30 different enclosures. Is there a specific name for just the cables without casing which would work with all the drives that I can look up? 82.44.55.25 (talk) 17:21, 3 October 2010 (UTC)

You want them easily interchangeable? An external drive docking station would probably be a good bet. Search your favorite computer supplier for "Hard Drive Docking." If you want to go a cheaper route you could run extension cables outside of the case, but I don't think you'll be able to swap those without powering down the computer first. You'll also probably need different ones for Parallel ATA and SATA, although you might get lucky and find one that does both. There are some external enclosures that do both, but you have to switch cables. Shadowjams (talk) 21:21, 3 October 2010 (UTC)

I looked into docking stations already but they specify sizes, and because of the different physical shapes of my drives (some are old and very bulky) I didn't think they would fit into docking stations designed for standard size drives. Basically what I want is a usb docking station, but without the casing; ie just the usb cable and wires to connect to the drive. Is that kind of thing manufactured? Does it have a specific name which I can search for? 82.44.55.25 (talk) 22:58, 3 October 2010 (UTC)

There are plenty of USB units that can connect to both PATA and SATA, eg [10] - won't that do what you need? Unilynx (talk) 22:59, 3 October 2010 (UTC)

Yes, thanks :) 82.44.55.25 (talk) 23:06, 3 October 2010 (UTC)

Wikipedia Copyrights

can i copy and past wikipedia is it a copywrite low? —Preceding unsigned comment added by 113.11.9.68 (talk) 19:28, 3 October 2010 (UTC)

See Wikipedia:Copyrights#Reusers.27_rights_and_obligations 82.44.55.25 (talk) 19:38, 3 October 2010 (UTC)

The text of Wikipedia is licensed under the Creative Commons WP:CC-BY-SA license (if you look at the bottom of the page, it says this in the small print). This means (approximately) that you can copy text as long as you cite Wikipedia. (Also, you can publish modified versions, as long as you make your modifications available under CC-BY-SA, also. This clause doesn't come up very often.)

Note that, depending on the setting, copyright law might not be the only constraint. For example, in academic settings, citations are necessary and plagiarism is unacceptable, even for works in the public domain. It's also often inadvisable to do long quotations of Wikipedia, even properly marked and cited, because encyclopedias are tertiary sources, which means that you're getting a "pre-digested" summary of the topic. Paul (Stansifer) 12:10, 4 October 2010 (UTC)

October 4

Restore iPhone texts and pics without doing a iTunes restore from backup

How can I restore my text messages and pictures with iTunes without using the restore backup option on iTunes? I don't want to restore everything like my settings and all that. Just my text messages and pictures. I am doing a fresh install of OS 4.1, thats the reason I ask. Thanks 76.169.33.234 (talk)Dave —Preceding undated comment added 02:12, 4 October 2010 (UTC).

Smartphone as meeting/seminar reminder via Google Calendar?

I've recently started a PhD where I'm having a lot of meetings and seminars at different times and could do with having my Google Calendar follow me wherever I go, to warn me in advance so that I don't miss things. I don't want to pay more than I need to, so ideally the phone (or some alternative but small device) could synchronise with Google Calendar via Internet-connected PCs (my desktop at home as well as my laptop and my desktop at work) via bluetooth or something similar and then beep a couple of times 15 minutes before a meeting is due to begin. What would be a good option for this? I don't think I'd use all the features of top-end models of phone. I'm happy to pick up e-mail etc. for free when I'm at a computer. Can you guys suggest anything? Thanks. --129.215.5.255 (talk) 09:27, 4 October 2010 (UTC)

Excel - add years to a date

How do I add years to a date in Excel? I have a column of dates, and in the next column I need the date 5 years after them. e.g. In the first column I have 01/02/2003, and in the next I need 01/02/2008. Thanks. DuncanHill (talk) 11:45, 4 October 2010 (UTC)

User YEAR, MONTH and DAY to extract year, month and day number from original date, add 5 to the year number, then use DATE to convert new year, month and day back to an Excel date value. So, if your original date is in cell A1, then your formula is:

=DATE(YEAR(A1)+5, MONTH(A1), DAY(A1))

Gandalf61 (talk) 11:57, 4 October 2010 (UTC)

Splendid, many thanks! DuncanHill (talk) 12:06, 4 October 2010 (UTC)

Spam replies

I get about 25 pieces of spam everyday. A large portion is Viagra, increase your dick size pills and Canadian/Mexican pharmacy stuff and assorted other crap. So I have started a policy. Every day I take 15 minutes out to send an email to each and every spammer with the message "fuck you spammer" in it (but about 500 of this phrase over and over in the body). Two questions. First, am I completely wasting my time or am I actually bothering them, or are they just bots? (bothering them back is the point). Second, is it possible this will actually work to get some of them to stop? Note that none of these are legit emails with any link in them or a website you can go to to ask them to remove you from their spamlist.

Another related thing. Is there anything else I can do to stop receiving this spam? Note that I do have my spam filter on and I use mail.yahoo.com. Thanks.--108.27.106.173 (talk) 13:48, 4 October 2010 (UTC)

It's worse than wasting your time; you're potentially sending emails to entirely innocent people. I get about 15000 spams a day over several domains, and they all have forged "from:" addresses; about 20% claim to be from my own domains, and about 5% claim to be from me. So mailing these is pointless. I occasionally get mails from someone who got a spam which had a forged email address appearing to be from my email address, and once a threatening phone call; I've twice had to call the police on people. Clicking on those "please remove me" things is useless too (for real spams, rather than promotional emails from companies you've actually done business with), as it confirms they've got through to a real person. Professional spammers don't care that you don't like their email, and nothing will make them stop. Reading your emails through a client with a decent spam filter of its own, like Thunderbird, will help. -- Finlay McWalter ☻ Talk 14:04, 4 October 2010 (UTC)

(e/c) Replying back to spam is a very bad idea. The messages are sent by a bot or even a virus-infected computer of some unsuspecting fellow. The messages usually have a forged "From" address field, which means you will be replying to somebody who did not send the message anyway. And if your reply gets back to the spammer, it only proves to them that your email address is valid, and therefore they will send you more spam.—Emil J. 14:07, 4 October 2010 (UTC)

Thank you for the information. I am holding my head now. Egad. It's so infuriating. They need to do something about this. Who exactly "they" is I don't know. There has to be a way that all the smart people out there can work together to stop this. I mean, half the messages I receive actually have "viagra" in the subject line. There has to be a way to stop these in transit. Anyway, following your responses I guess I'll abandon my "project". By the way, I'm not dumb enough to have opened all these emails from my home PC. I've only done this from a work MAC.--108.27.109.167 (talk) 18:32, 4 October 2010 (UTC)

Oh, "they" have plenty of solutions, but "they" want money from you for doing them, or want to be able to exempt themselves and their partners from the solution. The tragic truth is that, while only a tiny proportion of people buy stuff from the spammers, it's still enough for it to be worth their while. -- Finlay McWalter ☻ Talk 18:51, 4 October 2010 (UTC)

Stopping spam in transit is problematic, because it means that everyone has to share a universal definition of "spamminess". But Bayesian spam filtering can be very effective -- it essentially works by observing, for each word in the email, how many times it's been used before in spam and how many times it's been used in legitimate email. One side-effect of it was that spammers were attempting elaborate circumlocutions (or bizarre spellings) to avoid using spammy words; if they are literally using the word "viagra" (without resorting to spelling trickery), it suggests that the spammers have given up (it wasn't a very effective tactic), and are focusing their efforts entirely on recipients who don't have access to email clients with Bayesian filtering. This is a fascinating development, if so. Paul (Stansifer) 20:42, 4 October 2010 (UTC)

Mystery unconnectability

I'm running a computer with Windows 7 Ultimate x64, and Windows XP Professional x64 on another partition. A particular problem has been bugging me since I built it a few months ago, namely that whatever I do, I can never open a port. There are two other PCs on this network running exactly the same with no issue - same operating systems, same method of forwarding ports, same everything, making this all the more confusing. I've tried it on different ethernet ports too, with different cables, and through different modems and routers (but not in a different house, however we have switched ISPs during this time).

I've forwarded a port for utorrent in the router, as per instructions and exactly how it's done for the other computers (obviously not the same port, but just to clarify I've not missed that). canyouseeme, utorrent, deluge, azureus and the torrent sites I am a member of confirmed every time that the port is not in fact open, so the first variable I tested was my IP address and the port I was using. Everything else I changed, I tried with different combinations of these just to check.

I added exceptions to my firewall (Comodo) for all the torrent programs I tried, which changed nothing. Windows firewall is totally disabled, and disabling Comodo didn't solve the problem. I tried using DMZ on the router (sorry if that's incorrect terminology, I have a vague grasp on this but I'm not sure of the specifics) with the firewall disabled, which STILL didn't work. Everything was still telling me that the port was closed, or I was behind a firewall. It's the same in XP and 7.

Bizarrely, utorrent and Deluge now give me the happy little green symbol, and torrent sites tell me I am connectable - however, Deluge tells me there are no incoming connections, and canyouseeme still tells me the port is closed. I can torrent from seeds, but seeding myself is impossible. I don't often play online games so that's not much of an issue, but it's still frustrating and totally nonsensical (as far as I can tell).

Any ideas what the hell is going on? —Preceding unsigned comment added by 194.83.69.19 (talk) 14:38, 4 October 2010 (UTC)

How do I create virtual tours like this one ?

Hi, is there any free tool available to create something like http://www.mysorepalace.tv/360_Eng/index.html ? I suppose that it is made using some kind of photo-stitching software (or could it be using a video camera ?). Assuming that I have a camera (SLR or video), is there a way to create this on my own for free ? - WikiCheng | Talk 15:14, 4 October 2010 (UTC)

I believe VR photography is what you're looking for. QuickTime VR was the first example of this tech that I'm aware of. Comet Tuttle (talk) 16:30, 4 October 2010 (UTC)

bin vs iso

Resolved

For making a disk image from a cd or dvd, which is the better format to go for? 82.44.55.25 (talk) 15:18, 4 October 2010 (UTC)

From my experience, iso is supported more than bin. So, I would use iso. -- kainaw™ 15:27, 4 October 2010 (UTC)

Is there any difference between the two formats in terms of how accurately they save the disk contents? I read a while ago that iso isn't an exact copy and can't handle lots of sectors, but I can't seem to find where I read that to verify. 82.44.55.25 (talk) 15:32, 4 October 2010 (UTC)

The bin format handles multi-track and copy protection better. If you have a multi-track or copy protected disk that you are trying to copy and iso fails, you should use bin. For normal disks, iso works fine. -- kainaw™ 16:17, 4 October 2010 (UTC)

Ok, thanks :) 82.44.55.25 (talk) 17:18, 4 October 2010 (UTC)

Battery not detected in ancient MacBook

My MacBook (using Windows Vista) has been showing a nice "Battery not detected" warning for the past few days, and resetting the SMC (whatever that is) hasn't helped (did a Google search and found SMC-resetting options). Any ideas on what might do the trick and make my battery get detected?? Thanks in advance. 115.184.97.157 (talk) 15:44, 4 October 2010 (UTC)

Try it with another battery? That'll at least tell you if it is a problem with the battery and not the machine. I suspect it's the battery — they only have a limited life. If you can take it to an Apple store, they can take a look at that for you. --Mr.98 (talk) 18:10, 4 October 2010 (UTC)

Sudo security

I understand that giving sudo access to anything with a shell or a modifiable script is a security problem, but is there a risk if I enable access to a specific script that's not modifiable. For instance, if I have a script that reads a line from a 400 permissioned file, and that script is modifiable only by root (755 permissions), is there a security risk with that? I realize if the script itself allows for some user input there could be an issue, but assuming the script itself is fine, can anyone think of security issues with this setup? Shadowjams (talk) 20:04, 4 October 2010 (UTC)

I'm confused. Super-User has access to everything on the system - so any user who has permission to run sudo has (effectively) permission to run or access or modify any program, irrespective of file-permissions. "Sudo" does not have any other configurable access rights - it has permission to anything. Maybe I am misunderstanding your explanation? How exactly are you "denying" sudo access to any file? Nimur (talk) 20:20, 4 October 2010 (UTC)

See /etc/sudoers. The idea is to restrict what commands can be run as root (by a particular user). Of course, in this case one could just use setuid (and then check the real uid against an access list if needed) if the kernel in question does it properly for shell scripts. --Tardis (talk) 20:25, 4 October 2010 (UTC)

Sudo does have configurable access rights through the sudoers file (as Tardis points out). Sorry, I should have been clearer that I was hoping to restrict non-privileged users to a small set of programs/commands. I'm curious about the security risks of that. Shadowjams (talk) 20:29, 4 October 2010 (UTC)

It's better than nothing, but you still really need to think through what a malicious abuser of one of those sudo commands can do. Can they create a suid-root executable (or set an existing root executable suid)? Can they insert an executable, or a link to one, or a symlink, into a directory that's on root's path, and so get root to run that inadvertently (and ditto for other privileged accounts that run servers). Can they manipulate device files, mount points, or temporary files in a way that could let them gain full root (or persuade genuine root processes to do something unexpected)? Can someone abuse the dynamic loading mechanism, or the tracing mechanism, to persuade the sudoed executable to load code the abuser generated? And do any of the programs that the sudoers can run, or any subprogram, shell out? - all kinds of things like mail clients and text editors will let you. sudo is better than su, but there's a lot to consider. -- Finlay McWalter ☻ Talk 21:25, 4 October 2010 (UTC)

Incidentally I think sudo does take care of some of this (no time for research: cooking), in particular I hope it doesn't use the user's LD_LIBRARY_PATH or allow a user process to ptrace into sudo (surely the kernel will prevent that). -- Finlay McWalter ☻ Talk 21:48, 4 October 2010 (UTC)

Photo Editing

So I have some photos that I took of the night sky, with moderate exposure lengths (10-15 s). My camera isn't terribly good, and there's a lot of noise in the photos (example). I can visually tell what's a star and what's noise (at least for the bright stars), but would there be any way to tell some photo editing software to treat everything below a certain threshold as black, thus eliminating most noise, plus some of the dimmest stars? I realize that this wouldn't necessarily give me an accurate representation of how the sky looked exactly, but it would make it much easier to identify individual stars with a star chart. Buddy431 (talk) 21:55, 4 October 2010 (UTC)