Wikipedia:Reference desk/Archives/Computing/2009 July 29

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July 29

Game

What is the largest computer game ever made in terms of file size? Jc iindyysgvxc (talk) 00:47, 29 July 2009 (UTC)

Perhaps some game/movie hybrid? One were they would have to record more than the normal movie lenght? --_{Piotr Konieczny aka Prokonsul Piotrus| talk} 01:07, 29 July 2009 (UTC)

I am going to guess that it is World of Warcraft. Most of the file data is of course on the WoW servers. I'm sure they store a gigaton of data that tracks player activity. Tempshill (talk) 01:39, 29 July 2009 (UTC)

I remember back in the good old days (ha) of CD-ROM gaming when games that used multiple CD-ROMs ran ads telling you how many floppies it would have taken to play the game as it was (Under a Killing Moon advertised itself as being the equivalent of HUNDREDS of floppy disks!). Ah, well. But yeah, as noted, are you asking about total size installed on a hard drive, or kept on local disks, or distributed on a network? Probably different answers in all cases. --98.217.14.211 (talk) 15:10, 29 July 2009 (UTC)

Metal Gear Solid 4: Guns of the Patriots says "Guns of the Patriots is the first PS3 game that uses a full 50GB dual layer Blu-ray Disc, even after extensive efforts in data compression." This might be the current record for local data, since publishers are presumably loath to require two discs. -- BenRG (talk) 17:13, 29 July 2009 (UTC)

How many wikis are out threre?

Are there any reliable estimates on how many different wikis are out there? Wikia claims to host at least 1,500. --_{Piotr Konieczny aka Prokonsul Piotrus| talk} 01:06, 29 July 2009 (UTC)

It will be hard to reliably count. An overwhelming percentage of wikis are for "internal use only" in organizations, and are either not publicly visible or not publicly editable. If you intend to count non-public wikis, it will be very hard to come up with reasonable estimates. Nimur (talk) 01:32, 29 July 2009 (UTC)

Since the software is completely free in many cases, this question is like asking "how many non-wiki websites are there out there", but it's certainly lower than that. Chris M. (talk) 12:16, 29 July 2009 (UTC)

SQL Noob needs help

Hi All,

Is there an easy way to do this using sql: generate a table with two columns, one a field from the database and the other the number of times it occurs? Something kinda like: SELECT COUNT(CustID) AS totalOrdersFromCust FROM Orders_table WHERE CustID='id-here' except it will go and loop through the database so I end up with the number of times each customer has placed an order?

ex:

custID    totalOrders
1         24
2         16

etc..

I know there's gotta be a better way the me having to write a loop with an external app.

Thanks in advance! PrinzPH (talk) 02:16, 29 July 2009 (UTC)

select CustID, count(*) as 'NumberOfOrders' from Orders_table group by CustID --Nricardo (talk) 02:50, 29 July 2009 (UTC)

Resolved

Thanks Nricardo, Works! PrinzPH (talk) 22:31, 29 July 2009 (UTC)

Windows XP Hibernate Mode

Hello. How can I stop my computer from turning on immediately after hibernating it? There is more than enough space for hibernation. I read an identical question but it was unhelpful.

My computer spontaneously turns on only at 8 PM (EST) everyday. Regardless of when I hibernate my computer, the hibernation finishes but the computer turns on.

I was able to hibernate my computer even when I had an Ethernet card. Thanks in advance. --Mayfare (talk) 03:54, 29 July 2009 (UTC)

Reboot the computer and hit DEL (or whatever) to enter the BIOS screens, and scour the screens looking for the option to power on every day at a certain time, and, as was mentioned in the earlier thread, the option to power on when Ethernet packets are received. And any other options involving powering on; and turn them all off. Tempshill (talk) 04:05, 29 July 2009 (UTC)

Also go to Scheduled Tasks in the Control Panel and see if there are any tasks scheduled for 8 PM with "Wake the computer to run this task" checked in the properties (Settings tab). -- BenRG (talk) 08:18, 29 July 2009 (UTC)

How do I make my Ethernet card not turn on my computer when it receives packets? --Mayfare (talk) 16:40, 30 July 2009 (UTC)

Shell script issue

Resolved

When I run the following shell script, I expect domain names which return data to wget to be listed on the terminal where I run the script, and those which don't to be listed on /dev/pts/4. Instead, all domain names are listed on /dev/pts/4. I've tried commenting out the for loop and instead setting $line to just one domain; if I do this, it works fine. What am I doing wrong with the loop?

On a related note, when iterating wget over 2070 domains that may all be hosted on the same server, are any precautions necessary to avoid triggering the server's DoS defenses? NeonMerlin 07:05, 29 July 2009 (UTC)

#!/bin/bash
IFS="
"
for line in $(cat complete-scientology-domain-list.txt);do
  if wget -O - $line 2>/dev/null | grep ".*" >/dev/null; then
    echo $line
  else
    echo $line > /dev/pts/4
  fi
done

Setting IFS to newline means that any spaces in the input file will be treated as part of the URL. Don't set IFS and it should work. You should also put double quotes around all $line references. --Sean 14:41, 29 July 2009 (UTC)

To avoid triggering any defense mechanisms, check for a robots exclusion standard (GET /robots.txt). If the server is well-configured, the robots.txt file will specify rules for what you are doing (typically this means pausing between requests, e.g. pulling no more than one page per second, for example). Note that the robot exclusion "standard" is not really a "standard" - it is more of a guideline for "playing nice" with the host. A web server may choose to enact blocks or other defenses without specifying a reason. Nimur (talk) 15:40, 29 July 2009 (UTC)

Tried dropping IFS and quoting $line. Still doesn't work. NeonMerlin 16:21, 29 July 2009 (UTC)

Update: Does work correctly with the last domain name in the file (which doesn't end with a newline). Maybe it's an issue with how cat processes the line breaks. NeonMerlin 16:42, 29 July 2009 (UTC)

The file might have Windows/DOS line endings. Do a "dos2unix complete-scientology-domain-list.txt" and then try again. --Sean 14:01, 30 July 2009 (UTC)

Did the equivalent in kate, set sane timeout and tries for wget, and now works. NeonMerlin 14:25, 30 July 2009 (UTC)

Bluetooth mice

Are bluetooth mice any good? I'm getting a laptop and wireless mice with a small receiver and bluetooth mice seem to be in the same price range, but I've heard quite a bit of bad press towards bluetooth mice. Are they really worse than normal wireless mice? Do they interfere with WLAN much? Thanks. --antilived^{T | C | G} 07:11, 29 July 2009 (UTC)

Not sure if what I'm saying is accredited but my Logitec one works great, just like a regular mouse, and works on pretty much any surface but ones with reflective coating. I'm glad I have one; the touchpads are pieces of crap in my opinion. -- penubag  (talk) 07:29, 29 July 2009 (UTC)

Thanks for the info. Mind telling me the model? --antilived^{T | C | G} 10:45, 31 July 2009 (UTC)

Bluetooth shouldn't (and hasn't, ever, in my experience with them) interfere with WLAN, or any other wavelength. Bluetooth has its own frequency, which coexists with the rest of 'em. [flaminglawyer] 13:18, 29 July 2009 (UTC)

Both Bluetooth and 'WiFi' use the 2.4GHz band. (excluding WLAN that uses 5GHz) There is the potential for a bluetooth signal causing the WiFi to operate at a lower rate. Other devices also use this bandwidth (eg xbox 360 controllers, some wireless telephones etc), additionally your neighbours WiFi may also be wanting some of that bandwidth too.

For a discussion (very technical) see the first three links of http://www.google.co.uk/search?hl=en&q=bluetooth+wifi+interference&meta=&aq=f&oq= to complicate things it seems that different devices may be better or worse than others - in terms of avoiding bandwidth conflict, as well as the relative power of there signals - it's complicated (business have to employ specialist engineers see if a big system can work) but a 25% reduction in WiFi WLAN bandwidth is possible even expected, and it can be worse.

In general though they work fine (in my experience) in a home enviroment.

You can get wireless mice that operate at other frequencies (eg 750MHz I think) - most suppliers will have this info about there mice, if you look at the tech specs.

If you are using WiFi WLAN as networking between computers and you require it to be as fast as it can possibly be then bluetooth is something to factor out. Under most conditions (internet browsing, small file transfers between computers) it shouldn't be an issue.

A lot depends on were you live - a new york office is going to be much more demanding (due to the number of devices all around) than a house in the middle of a park.83.100.250.79 (talk) 19:49, 29 July 2009 (UTC)

The primary reason why I'm concerned about interference is because my desktop mouse interferes with my WLAN and freezes for a few seconds once in a while. If all bluetooth is gonna do is slow down WLAN I'm fine with it, since it's not like I'm transferring files over it anyway. --antilived^{T | C | G} 10:45, 31 July 2009 (UTC)

Updating system software on a PSP 2003

Does anyone know how to update system software on a PSP 2003?Chevymontecarlo (talk) 08:07, 29 July 2009 (UTC)

See Sony's PSP update page for instructions, at the bottom of the page, on updating your PSP, by using a PC, a UMD disc, or, the easiest way, logging in to a WiFi network anywhere and choosing "Network Update". Tempshill (talk) 15:50, 29 July 2009 (UTC)

It worked - thanks. Chevymontecarlo (talk) 10:34, 30 July 2009 (UTC)

imaginary vbScript

Can vbScript handle complex numbers? If so, how does the syntax work? Thanks —Akrabbim^talk 14:38, 29 July 2009 (UTC)

According to [1] no.

There are modules that will add support via functions eg [2] , there are more extensive librarys which could be adapted using the same methods. eg [3]

A here's a list of some languages that do [4] if you need it.83.100.250.79 (talk) 14:51, 29 July 2009 (UTC)

trackboard

complete information about trackboard in computer —Preceding unsigned comment added by 116.68.94.36 (talk) 14:58, 29 July 2009 (UTC)

The only computer-related "trackboard" I've found is this product. If you have a specific question, please ask again and remember that you're dealing with people, not a search engine. --LarryMac | Talk 15:02, 29 July 2009 (UTC)

Google finds a company by that name that makes keyboards with embedded trackballs. But maybe you meant circuit board? -- Finlay McWalter Talk 15:03, 29 July 2009 (UTC)

or perhaps Stripboard ? -- Finlay McWalter Talk 15:14, 29 July 2009 (UTC)

Or maybe the mysterious semi-vaporware, Phantom Lapboard? Nimur (talk) 15:44, 29 July 2009 (UTC)

Did you mean Touchpad aka 'Trackpad' ? 83.100.250.79 (talk) 19:33, 29 July 2009 (UTC)

linux backup/restore

A couple of kinda related linux questions
1)when i installed linux (fedora 10) i installed /boot, /, and /home as separate partitions. Now the other day i had a slight hd drive problem, and decided i needed to reinstall /boot, how can i do this without having to reinstall /, as when i used a live cd installer it told it needed to install /
2) after reinstalling fedora i used rsync under root to copy back all the files, as i had backed up / on a removable hard drive, but it doesnt seem to of copyed back programs, the files seem to be there in the backup folder but it doesn't seem to of copyed back to my pc, anyway to fix this?
3) i currently use rsync under cron doing this command "01 18 * * * root rsync --archive --compress --backup --delete --exclude-from=/home/rob/exclude / /path/to/backup/directory' and exculde the following /media/ /proc/ /sys/ /tmp/ /mnt/ /usr/share/man/
a)is there any other files/folders that can be excluded
b)would running rsysnc with any different/extra options be more beneficent?
thanks--90.207.181.210 (talk) 16:49, 29 July 2009 (UTC)

looks like 2 was due me writing a bad path on the rsync to copy the stuff back--90.207.181.210 (talk) 10:56, 1 August 2009 (UTC)

MATLAB string analysis

I have a string:

>> line = # GHZ S RI R 50.000000;

I want to grab each element as an individual string, and then convert the last into a number. After looking around, I tried this and got an error:

>> header = regexp(huh,' ','split')
header = 
   '#'    'GHZ'    'S'    'RI'    'R'    '50.000000'
>> str2num(header(6))
??? Error using ==> str2num at 33
Requires string or character array input.

For all I can tell, header looks like a matrix of strings so I don't know why str2num isn't accepting it. Maybe it's just because I don't understand all this regular expression nonsense, but what am I doing wrong? Is there a better way to split this string? Thanks, —Akrabbim^talk 19:04, 29 July 2009 (UTC)

Does MATLAB indexing start at 0? If so, you'd want header(5). --19:37, 29 July 2009 (UTC)

No, it doesn't. It starts at one, so:

>> header(6)
ans = 
   '50.000000'

—Akrabbim^talk 19:40, 29 July 2009 (UTC)

While you're waiting for the answer - I can suggest a few things to try to see if you can find out whats going wrong - try the "ischar" and "isnumeric" functions on header(6), try the expression str2num("50.000000") to make sure the decimal isn't confusing it, also try passing header(6) to a single non arrayed variable eg 'tempv' and then using "str2num(tempv)" - to make sure the array isn't confusing the type checking on the function. I can;t actually see anything wrong myself.83.100.250.79 (talk) 20:28, 29 July 2009 (UTC)

I'm just guessing (again), but since nobody else has jumped in yet ... I've been perusing the online documentation and can't find anything obvious, but can you try header{6} ? i.e. curly braces instead of parentheses. I think header might be a "cell array" and you need to access the contents of a cell rather than the cell itself. --LarryMac | Talk 20:33, 29 July 2009 (UTC)

That does seem to be it - described here [5]. Curly brackets should fix it.83.100.250.79 (talk) 21:35, 29 July 2009 (UTC)

Actually I'm getting a bit confused because 'regexp' according to [6] has a different syntax, and doesn't do what you want - it checks for matches oh "huh" must be the strings name.- you want to tokenise.??

You could try "strtok" as well , see [7] —Preceding unsigned comment added by 83.100.250.79 (talk) 20:44, 29 July 2009 (UTC)

Larry, you are right. Is is a cell, so header{6} is what I need. I didn't know that cells were any different, so thanks for the educational link 83. —Akrabbim^talk 15:54, 30 July 2009 (UTC)

Resolved

Time Machine on a Mac

Hi. I have recently purchased a 500GB Time Capsule to back up my iMac and MacBook Pro. I first set up Time Capsule on my iMac and all was hunky dory. However, when I tried to set it up on my MacBook Pro, it came up with 'Time Machine Error. The backup disk image could not be created.'. I haven't the faintest idea what this means or, more importantly, how to rectify it. Could someone help me out please? Thanks. 92.0.232.90 (talk) 19:42, 29 July 2009 (UTC)

That error means that the Time Machine program could not create the database for saving old versions of your file. According to this Apple discussion forum, you need to set your computer's "Network Name" (in the System Preferences utility, this can be set in the "Sharing" tool, under "Computer Name"). Time Machine probably requires a computer name to be properly set so that it can create a unique database just for that computer. Nimur (talk) 20:01, 29 July 2009 (UTC)

This is no doubt going to jinx it but setting a Network Name (which I did not have before) got everything going just like with my iMac. Thanks Nimur! 92.0.232.90 (talk) 20:22, 29 July 2009 (UTC)

Apples ownership of adobe systems

Can you tell me what the high watermark percentage of Apples ownership of adobe was? I know that at one time they owned more than 16% but I think the high watermark was closer to 25%. Brafferty (talk) 20:31, 29 July 2009 (UTC)

Switching from GPL to closed source

The AutoHotkey article states that the authors released their code under the GPL, became frustrated, and then declared their future work with the code base was to be closed source. In the cited source (it's a chat board thread), the apparent author of the software states, "As we wrote all the code we can depart from the GPL if we choose. Previously downloaded source would still be under GPL (as per the license) but new copies of the source would be under whatever license we care to make."

Is this correct? I know there's very little case law in any country regarding the GPL, but I guess I had thought that once the author releases code under the GPL, he is a licensee as well, and as a user of the code, would have to abide by the GPL's terms, including releasing free, GPL'ed source code of any derivative works. If the author's statement is correct (and it does sound logical to me that he doesn't have to be a licensee) then that's an interesting wrinkle. Tempshill (talk) 20:46, 29 July 2009 (UTC)

My understanding is that only the copyright holders may sue if there is a breach of the GPL. If all copyright holders decide that they do not want the GPL and will not sue about ending the GPL license, then the license may be changed without any legal problems. It is the perception of the people that once something is GPL it is absolutely free and owned by the world. That is a completely false perception. Having such a perception leads to the perception that the copyright holders are stealing from the world by taking their code closed source. -- kainaw™ 20:56, 29 July 2009 (UTC)

The question is really about whether a developer who has moved to closed source can sue YOU for using it under the old open source agreement, not whether the developers will sue each other over it. --98.217.14.211 (talk) 21:15, 29 July 2009 (UTC)

(edit conflict):I can't see any stand up argument that would prevent someone/group changing the licencing arrangements for their own work (assuming no other contributers disagree) applying to future products (retroactive license changes are non-runners/difficult/debateable though) - the license isn't a contract that requires the producer (ie the one with the intellectual property rights) to continue to license all their work in perpetuity.

As you say the manufacturer is not a licensee.I'm not a lawyer83.100.250.79 (talk) 20:57, 29 July 2009 (UTC)

Copyright holders can release their code under multiple, non-exclusive licenses at different times. They are not obligated to release their new code under GPL just because the old code was, if they were the original copyright holder (the one who is issuing the licenses in the first place, not a derivative user). However, they cannot "withdraw" the GPL license on the original code. See [8] and [9]. --98.217.14.211 (talk) 21:15, 29 July 2009 (UTC)

The Mocha (decompiler) was "licenced" (if one can count a single line in a readme.txt as a licence) thus: "The distribution archive (file "mocha-b1.zip") may be distributed freely, provided its contents are not tampered with in any way." - it's no GPL or open source (only .class files were distributed) but it was a distribution-permissive licence. According to this page the author died, and Borland acquired the rights to Mocha. The author of that site quotes an email he says he received from Borland telling him that, despite the readme, he couldn't distribute it any more. He says he told them to shove off and he's still distributing the software. The situation should be clearer for GPL software being retroactively pulled (as opposed to simply relicenced-from-now-on), as the GPL is a properly written licence rather than a passing one-liner. Note, incidentally, that to contribute to some GPL software (that is, to get your patches into the core tree) you need to assign copyright (not just GPL licence); I think that's always been the case for MySQL - the current Sun scheme is a bit more liberal, but you still need to jointly assign copyright (ref) - which would allow Sun (or Oracle, soon) to take future revisions of the software closed source. -- Finlay McWalter Talk 21:44, 29 July 2009 (UTC)

The process is actually pretty simple. If (say) version 1.0 of a particular piece of software is released under the GPL, then the copyright owner (and nobody else) can choose to change the license on (say) version 1.1 to be a closed-source license. However, the source code to version 1.0 can still be redistributed under the terms of the GPL - it can be improved upon, added to - even made compatible with version 1.1 - and it'll STILL be under the GPL. However, the copyright holder's version 1.1 is now closed source - and you're not allowed to redistribute it. Only the copyright holder can do make that decision...and for most OpenSourced software were there are several (if not dozens or even hundreds) of authors, it takes the agreement of every single one of them to change the license terms (unless it's possible to identify the changes that a particular person made and back them out such that none of his copyrighted additions remain in the package). So most large/common packages are safe and cannot ever be closed off. But even when the original author does own the entire copyright - the community has lost nothing. The version that was out there on the day before the license changed is still out there under GPL - and you can try to put a team together to maintain and improve it. Since the community-maintained and the (now) commercially maintained packages are competing with each other on an (initially) level playing field, there is no reason to assume that the package will not continue to thrive as an OpenSourced package. SteveBaker (talk) 23:55, 29 July 2009 (UTC)

Thanks everyone for the answers. Tempshill (talk) 00:17, 30 July 2009 (UTC)

Video Conversion

Is there any free software that i can use to convert dvr-ms (the format used by recorded tv from Windows Media Center) to a common format such as mpeg or avi. I have tried avidemux but the audio is really out a sync and i generally cant get it to convert correctly. Any ideas on good video conversion software or how to use avidemux properly would be greatly appreciated. —Preceding unsigned comment added by 86.177.127.22 (talk) 21:07, 29 July 2009 (UTC)

Some options for editing, transcoding, and simple rewrapping are discussed in the DVR-MS article. -- Finlay McWalter Talk 22:07, 29 July 2009 (UTC)

MEncoder and ffmpeg support conversion of dvr-ms files. There's a good GUI for ffmpeg available here // 21:48, 30 July 2009 (UTC) —Preceding unsigned comment added by 4k01 (talk • contribs)

Downloading flash-based video

I'm looking for a program or browser-plugin that enables downloading of flash based video from a web site, specifically this site, in a format playable by media players such as Windows media player, VLC media player or Quicktime. OS: Windows XP, or Linux (Debian or Ubuntu). Anyone aware of such a beast? --NorwegianBlue ^talk 21:16, 29 July 2009 (UTC)

I was able to download the FLV file using FlashGot in Firefox. VLC can play FLVs and there are no doubt codecs that let you play it in everything else as well. --98.217.14.211 (talk) 21:24, 29 July 2009 (UTC)

Thanks a million! Worked like a charm. --NorwegianBlue ^talk 21:55, 29 July 2009 (UTC)

Resolved

Addendum: I'd like to add, in case anyone else is interested, that the file was easily transcoded to a format recognizable by Windows Media Player, using the transcoding wizard of VLC media player. --NorwegianBlue ^talk 22:12, 29 July 2009 (UTC)

Also the VLC Player can output video as ASCII art, realtime.. probably worth a download just for that.. 83.100.250.79 (talk) 15:15, 30 July 2009 (UTC)

USB flash drive size conventions

Hello wikipedia!

Why do USB flash drives come mainly in sizes related to binary numbers? 256Mb, 1Gb, 8Gb, etc? Hard drives and CDs just have a number, presumably the biggest number they could get with the current technology.

A google search for 5gb flash drive returns a fraction of the hits for 8bg flash drive.

Thanks Fenton Bailey (talk) 21:53, 29 July 2009 (UTC)

The drives are that size because the flash memory chips they contain are sized in powers of two. Those chips (like almost all memory chips, like the DRAM chips in your computer for example) use a memory addressing scheme to refer to the individual chunks of memory they contain. Those memory addresses are passed around on so many wires, each of which carries just a 1 or a 0; (simplifying a tad) that's an address bus. If I have n wires in my address bus, I can address up to 2^n chunks of memory. You could, if you really wanted, have n lines of addressing but a bit less than 2^n bytes of memory, but really there's no point in doing that (and it makes code that deals with the device as a whole more complicated, as it has to remember that not all valid address values correspond with memory). Additionally, frankly that's how electrical engineers have been doing things for so long that their brains, and the tools they use to do things, work much better in powers of 2. Now you might ask why this isn't true for hard drives too - again, hard drives expose the underlying technology, but as the geometry of hard disks is a lot more complex this doesn't make for nice powers of two, but a bunch of weird numbers. Lastly, back on flash-usb disks, you could ask "why couldn't they put in a 4Gb chip and a 1Gb chip and release a 5Gb drive" - they could (there's really only room in a usb flash drive for one or two chips) but the cost increment for them in going from a 1GB to a 4Gb chip is so little that they might as well put in 2x4G at little extra cost, and they can charge you (quite rightly) a good bit more. -- Finlay McWalter Talk 22:05, 29 July 2009 (UTC)

Given the fact that pretty much every decent flash drive has circuits for wear levelling, the extra complexity for remembering which addresses are valid and which ones aren't is probably trivial. -- 128.104.112.87 (talk) 00:52, 30 July 2009 (UTC)

Is that really true? The flash drives I've used all had capacities in decimal MB and GB (the 256MB ones hold about 256,000,000 bytes, the 2GB ones hold about 2,000,000,000 bytes). A 1GB drive is not twice the size of a 512MB drive, it's only about 95% larger. I know they have some extra sectors for defect management or wear leveling or whatever, but I don't see why the ideal fraction of extra sectors would be 1.024ⁿ where n is 2 or 3 depending on the unit used to describe the drive size. -- BenRG (talk) 18:15, 31 July 2009 (UTC)

The acid test is to crack the thing open and we'll look up the flash memory part's datasheet. -- Finlay McWalter • Talk 18:33, 31 July 2009 (UTC)