Wikipedia:Reference desk/Archives/Computing/2010 July 12

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July 12

Locked file

Is there any way to get into a file (such as a word document or a PPT presentation) if it's been password protected and the password has been forgotten? DRosenbach ^{(Talk | Contribs)} 01:45, 12 July 2010 (UTC)

We need the exact file type and the version of the program used to make it. It depends. --mboverload@ 03:35, 12 July 2010 (UTC)

Recent versions of Microsoft Office use very strong encryption. It is not feasible to break the passwords on such files. You can attempt a brute force attack, but it may take an arbitrarily extremely long time. Nimur (talk) 20:42, 12 July 2010 (UTC)

Very long, yes. Arbitrarily long, no. And before brute-forcing it, try a dictionary attack. Or rename it "boulder_nuke.ppt", address it to "bin Laden, Pakistan", and get it off the NSA in 50 years, when it becomes declassified ;-). --Stephan Schulz (talk) 21:09, 12 July 2010 (UTC)

Poor choice of words on my part. "Arbitrarily long" implies "infinite amount of time", which is not the case here. Nimur (talk) 21:27, 12 July 2010 (UTC)

Form

What did I do wrong with this? I followed all the instructions in the dreamweaver book. Thanks Kayau Voting IS evil 02:16, 12 July 2010 (UTC)

What is the issue on your end? Do you just not receive anything, or is it another issue altogether like garbled text? Does submitting it just not go through? (I'm not very fond of Dw myself, actually.) sonia^♫♪ 04:57, 12 July 2010 (UTC)

I've tried using the form myself multiple times (like, for a year already!) and it doesn't work. Try and see for yourself... I've tried Yahoo! Answers, but you know those people, it's an opportunity for them to advertise their web design packages. Kayau Voting IS evil 07:57, 12 July 2010 (UTC)

I know nothing about dreamweaver, but your page could do with running through a spell checker. Pseudonym. Anonymous. -- SGBailey (talk) 08:21, 12 July 2010 (UTC)

Ah, I see. Sorry for not trying it earlier, btw. So the form opens mailto:youraddy directly for the viewer instead of collecting input and sending it to you. From looking at the source, it appears to be because you've got <form id="form1" name="form1" method="post" action=""> with nothing in the action field. That's what tells the form what to do, and should link to a script afaik. I'm not sure if the omission is a Dw bug. Actually, I'm afraid I'm not going to be of much help here beyond that, sorry. I find that some of Dw's scripts are either overcomplex or not specific enough for my liking. It frustrates the director immensely since he went out and purchased CS5 for all five project teams which took him out of pocket a good deal. But that is, of course, irrelevant. sonia^♫♪ 08:28, 12 July 2010 (UTC)

This is how the mailto form works on many browsers. See this article. I don't think it's a Dreamweaver problem, I think it's an artifact of modern browsers not supporting the mailto method in the way you're expecting it to be supported, probably as a security issue. If you want an easy means of seamlessly getting form data, a PHP script is probably a better way to go. --Mr.98 (talk) 13:35, 12 July 2010 (UTC)

No... I think the problem is that you have 2 form elements on your page. The first one is empty, and does nothing. I think when you hit the submit button, it's submitting the first form and not the second. Just delete the first form from your code, and you should be fine. The offending form looks like this: <form id="form1" name="form1" method="post" action=""></form> Indeterminate (talk) 13:56, 12 July 2010 (UTC)

There is nothing wrong with two form elements on a single page. You have to make sure that things are going to the right form, to be sure, but I don't see that as being a problem here. --Mr.98 (talk) 14:17, 12 July 2010 (UTC)

Actually I'm rubbish at HTML (that's why I use Dreamweaver! :P). I'll try deleting that code, if I ever manage to find it. The only code-ish stuff that I know a little about are VB (because they make us learn it at school) and Actionscript (and I've forgotten most of the Actionscript that I've read about.) Kayau Voting IS evil 13:31, 13 July 2010 (UTC)

why youtube doesn't allow downloading and saving of videos

Youtube does not allow users to download and save videos in our computer. I am just wondering if that is a business decision or a legal decision. Business decision in the sense, if youtube allows to save, we will not go again and again to watch the same video. so, if they don't allow to save, youtube makes lot of money. Legal decision in the sense, there may be a law saying that video sites can not allow option of saving videos without verifying whether the poster is the copyright holder or something else in DMCA. Can anyone tell which is true? —Preceding unsigned comment added by 218.248.84.91 (talk) 05:50, 12 July 2010 (UTC)

It's never "allowed" it, but there are ways to do it. (E.g. using KeepVid or other similar sites, or various Firefox plugins.) As for why, it is almost certainly a combination of 1. YouTube wants you to keep visiting their site, because they get ad revenue; 2. Copyright holders probably want the same to happen, both because of the control and because they get some of ad revenue as well. I don't think there's any legal difference, in terms of DMCA, between serving content in a flash applet or letting users very easily click a "download" button. The content technically IS downloaded on the user's machine either way, and, again, as stated, it is pretty easy to download the videos if you know what you are doing. --Mr.98 (talk) 13:42, 12 July 2010 (UTC)

Certain videos on Youtube are delivered as raw FLV streams to a player embedded in a Flash applet in your browser. Such streams are delivered over HTTP or wrapped inside a similar protocol (RTMP). As Mr. 98 has correctly commented, these FLV streams can be easily intercepted (many third-party websites can help streamline this downloading process). However, more recently Youtube began to use Flash Media Server to deliver some content (especially the new commercial content that is not user-uploaded). It is not trivial to intercept the video because it is securely transferred over a TLS connection between a specialized server and a secure signed Flash applet inside your browser, and (because Adobe Flash 10 now supports "video hardware acceleration"), the video stream can be encrypted all the way down into your operating system to the video driver layer (i.e., unless you have written a custom video driver that spoofs a signature, your efforts to intercept those video streams and save-to-disk constitute a man in the middle attack, where your interception would lie between the secure server and the signed video driver. Such interceptions are infeasible). At the same time, Youtube has also begun to serve some video content using HTML5 video - a free and unencumbered open protocol that does not require Flash or any other specific video player. Saving these streams to disk is as simple as viewing the page source and grabbing the video link; the stream is an H.264 video delivered over HTTP. I can only opine that within Youtube, there must be an ongoing, intense internal debate that is flapping between the extrema of very strong efforts to provide digital rights management and very strong efforts to provide open, unencumbered access to content. Both models have business- and legal- justifications. Nimur (talk) 20:51, 12 July 2010 (UTC)

Just as a note, all of these DRM attempts still fall victim to the analog hole, or, without even bothering to be analog, any sophisticated screen capture software. --Mr.98 (talk) 23:43, 12 July 2010 (UTC)

Analog hole will always trump all DRM schemes. Screen capture, however, usually can not capture hardware overlay buffers. Nimur (talk) 00:00, 13 July 2010 (UTC)

Until direct neural connections to the brain. Then the RIAA will have won. --mboverload@ 07:04, 14 July 2010 (UTC)

GPU compatibility

Hi, I just bought an Asus motherboard (P7P55D-E) and a Gigabyte GeForce GTX 465, will the gpu be compatible with the asus board since it's a gigabyte version? The guy in the store got them both off the shelf for me knowing they were to be used together so I didn't think anything of it at the time, I'd rather make certain before I try it though. Thanks in advance Benjamint 06:29, 12 July 2010 (UTC)

You're fine. AFAIK, the only time you'd have to worry is if you were trying to set up Nvidia SLI or ATI CrossFire (with two video cards), and your board doesn't support that (since it only has 1 PCIe x16 slot). Almost any modern single video card will work fine with almost any modern motherboard. Indeterminate (talk) 13:43, 12 July 2010 (UTC)

Excellent, Thanks Benjamint 14:18, 12 July 2010 (UTC)

addressing

What the difference between physical address and logical address —Preceding unsigned comment added by MinaAli (talk • contribs) 06:53, 12 July 2010 (UTC)

• Physical address: MAC address
  
• logical address: IP address

Benjamint 07:39, 12 July 2010 (UTC)

Well a physical address will have the exact directions on how to use the device. This may include IO port or interrupt numbers. A logical address will be a more friendly name such as D: drive or /dev/cd. Graeme Bartlett (talk) 11:48, 12 July 2010 (UTC)

Note that the physical/logical distinction is relative. For example, from the point of view of a programmer, an array index might be a logical address and the memory address a physical address, but dip down into the point of view of the virtual memory system, and the memory address the program sees is logical, and the underlying location is the physical address. (There's probably at least one more layer down until you hit something that specifies a location on the RAM chip itself.) Paul (Stansifer) 03:12, 13 July 2010 (UTC)

Good point, I just automatically assumed a networking context which probably wasn't helpfull. Benjamint 13:05, 13 July 2010 (UTC)

Move "my" stuff to another partition

I have recently repaired/reinstalled Windows XP and I thought it might be a good idea to keep the personal stuff on a separate partition.

1. Is it better/easier to move all of "C:\Documents and Settings\<username>\..." or just the "C:\Documents and Settings\<username>\My Documents\..." to D drive?
2. Should the same be done for the other users (Administrator, All Users, Default User, LocalService, NetworkService, etc.)?
3. How do I convince XP to always recognise the new location as the default (I'm thinking a registry change is what's needed here)?
4. Is the process much the same on Vista and 7?

Astronaut (talk) 12:41, 12 July 2010 (UTC)

That whole assemblage of stuff is called the user profile. Inside that is a bunch of stuff, including configuration settings, various files you'd normally know about and lots you wouldn't, and the Application Data folder, which is normally hidden but which (on XP, and very vexingly) contains both borderline junk (web browser cache files) and vital stuff (that's where Thunderbird keeps all you email). So:

1. do the whole profile
2. see below
3. I haven't tried it lately, but this should do it.
4. Dunno. Vista introduces (at last) a decent segregation between roaming stuff (the important files you care about) and local (various caches and junk, that you don't). User profiles are stored in a slightly different location (see home directory).

But I have to ask - why do you think this is a good idea? A separate partition (particularly on the same disk) is no substitute at all for a decent backup. Personally I don't have enough personal configurations and settings to justify backing up the whole profile, so I just cherrypick MyDocuments and Thunderbird's profile. If you want an image with which to reconstruct the whole computer, I'd recommend you image the whole disk wholesale. -- Finlay McWalter • Talk 13:03, 12 July 2010 (UTC)

My company used to do this. It never made any difference in recovering data when the hard drive went bad. Just leave it on the default partition and make your life simple. --mboverload@ 03:59, 13 July 2010 (UTC)

One good reason in Linux for keeping /home on a separate partition is that this allows you to install a new version, or a new distro, and try it out without getting rid of your old one, but still having access to all your data and documents. (Admittedly there are a few gotchas, like if you're using different KDE versions and they're both hitting your .kde directory, but it works reasonably well if you have a good tolerance for fixing stuff like that.)

It strikes me as possible that you might be able to do the same sort of thing in the Windows world. It's probably not well-documented for the end-user, but I wouldn't be surprised if there's a way to coerce the install disks to do this if you know the right magic words. --Trovatore (talk) 04:52, 13 July 2010 (UTC)

The reason to do this is to experiment. However, the practical application I have in mind is when fixing my sister's kids' PCs. They regularly get all manner of things going wrong and I have had to reinstall Windows XP several times so far this year. One solution I've adopted is make a copy of the OS default setup in a hidden partition, but I still spend a long time backing up their extensive collection of music, images and video (and a little homework too!) before I can overwrite the corrupted system with the one I saved in the hidden partition. If their stuff was on a separate partition, I think it would make this a lot quicker. Astronaut (talk) 04:14, 14 July 2010 (UTC)

Considering how often many users (not just kids) manage to screw up XP, I always partition into C: for programs and D: for data. It's trivial to move My Documents for a user onto the D: drive. Just right-click My Documents and pick 'Properties'. Then click the [Move] button. Browse to the D: drive and [Make New Folder]; call it 'FredsDocs' or whatever. You then get asked if you want to move the present contents of My Documents there, so click [yes]. Job done. It's possible to relocate the mail folder on most mail clients similarly, although as webmail gets more popular, that is becoming less necessary. Anyway, as long as you can persuade them to organise their data within My Documents (and not the desktop!), there'll be a single point to backup from. More importantly, after a fresh install on C: it's easy to point My Documents back to D:\FredsDocs. In my experience, you'll do many windows re-installs well before any hard drive dies (apart from 20GB Hitachis), so it's worth doing. --RexxS (talk) 03:21, 16 July 2010 (UTC)

vista / 7 - orange program higlight

Hi. A recently installed program has the background colour highlighted an orange colour - what does this signify (I gave the program permission to change file associations etc), and how to get it to go away? (that's in the program list - not the taskbar - the program isn't running I think) 77.86.10.49 (talk) 15:42, 12 July 2010 (UTC)

Newly installed programs are highlighted yellow in the start menu (and its submenus) for a while (I don't know the criterion whereby the highlighting goes away). That's just so you know what's new. You can disable this by unchecking the "Highlight newly installed programs" item in the task bar's configuration screen. -- Finlay McWalter • Talk 15:48, 12 July 2010 (UTC)

ok thanks, I was worried it was something to do with permissions, security certificates etc.

Resolved

Templates...AGAIN!

Hi, I have another modding question for you...well, it's the same one. I've installed the Parser Functions extension on my wiki, but when I test it out, it still shows the syntax! HELP! Velociraptor888 15:56, 12 July 2010 (UTC)

Hello! It's been 3 hours since I've posted and still don't have a reply. Velociraptor888 17:57, 12 July 2010 (UTC)

Like it says at the top of this page (and like you were reminded last time): "When will I get an answer? It may take several days". Please be patient. If someone can help (and if they want to), then they will. But continuing to ignore the basic instructions at the top of the reference desk pages is a sure way to make sure people DON'T want to help you... (and sorry, but I don't know the answer to your question)ZX81 ^talk 18:26, 12 July 2010 (UTC)

Don't feel bad, I asked several questions that didn't get replies. --Chemicalinterest (talk) 00:52, 13 July 2010 (UTC)

well, I could answer his question, but I'm pretty sure if he follows the same link I gave him last time and looks around he could figure it out for himself. I mean, he's got a lot of anxious energy on the issue; let him put that impatience to good use. --Ludwigs2 01:31, 14 July 2010 (UTC)

Yes, well, how do you create safesubst? It's driving me crazy! Velociraptor888 18:26, 15 July 2010 (UTC)

videos konvertieren

hi, wie kann ich videos, die ich vom fernseher über einen festplattenrecorder von panasonic dmr-eh595 augenommen habe-auf dvd+rw gebrannt habe in ein format umwandeln, das der bresser mini-projector led-mp2 abspielen kann? er ist für videoformate rm, rmvb, avi(mpeg4),flv, dat, vob ausgelegt. —Preceding unsigned comment added by Achimb (talk • contribs) 16:38, 12 July 2010 (UTC)

Hi Achim. Wrong formatting (fixed now) and wrong language. However, I suspect you can use a program like HandBrake to recode the DVD. --Stephan Schulz (talk) 16:41, 12 July 2010 (UTC)

Also, HandBrake in German Wikipedia. Nimur (talk) 18:30, 12 July 2010 (UTC)

Any weighted widget to hold down keys at startup?

Anyone know of any thing to use to hold down a specific key or keys on a keyboard? --70.167.58.6 (talk) 17:05, 12 July 2010 (UTC)

A weight. They are used for scales - especially in chemistry and physics. -- kainaw™ 18:00, 12 July 2010 (UTC)

You may be able to use a software keyboard or a software program to achieve your objective without actually holding down physical keys. What are you trying to do? Nimur (talk) 18:31, 12 July 2010 (UTC)

I need to hold down a key at boot. And I need to do this to a lab full of computers. --70.167.58.6 (talk) 18:37, 12 July 2010 (UTC)

What would be the estimated weight to keep a key depressed? --70.167.58.6 (talk) 18:37, 12 July 2010 (UTC)

0.5 to 0.8 newtons, or around 50 grams or 2 ounces. It depends on your keyboard. Nimur (talk) 18:52, 12 July 2010 (UTC)

For an IBM model M, this says 60 to 70 gm (which is in the same range as Nimur's reference). -- Finlay McWalter • Talk 18:56, 12 July 2010 (UTC)

I've seen a screwdriver jammed into a keyboard for this purpose. It may damage some of the keys, of course. Comet Tuttle (talk) 20:01, 12 July 2010 (UTC)

I used to do this fairly often with games, however it doesn't sound like it would be the sort of thing I'd want to do with a lab full of computers Nil Einne (talk) 00:08, 13 July 2010 (UTC)

Instead of a screwdriver, you can use a plastic pen cap. We do this here at my work for the keyboard of one of the tools. To home the robot, you need to hold down the home key. Doing so starts to hurt in time. So, we stick a pen cap in the keyboard and go about doing other things. Dismas|^(talk) 00:16, 13 July 2010 (UTC)

For clarification I should mention I primarily used to use kitchen utensils Nil Einne (talk) 04:35, 14 July 2010 (UTC)

Before you proceed doing stuff with software or weights....why do you want to hold down certain keys on the keyboard? Are you trying to boot to PXE? There are BIOS options for that. There must be an easier solution here. --mboverload@ 01:53, 13 July 2010 (UTC)

You can just fold up a piece of paper about 8 times to make a thick stiff wad, that will fit between the keys and hold one down. Graeme Bartlett (talk) 02:21, 13 July 2010 (UTC)

I've heard that golf balls are the right size and weight for holding keys down. But I agree that a software solution is preferable, if possible. Paul (Stansifer) 03:06, 13 July 2010 (UTC)

A former co-worker of mine used his old-fashioned stapler (made entirely out of metal and with a rectangular shape, not one of these newfangled light-weight plastic thingies) to hold down the Ctrl key (which was enough to keep the screensaver from activating, much to the dismay of the IT Security staff). -- 78.43.71.155 (talk) 20:31, 14 July 2010 (UTC)

Virtual RAM

The computer I'm using only has 2GB of RAM. I can't afford / have the ability to buy additional RAM, and the computer only has two RAM slots, both occupied bu 1GB RAM each. However, it occurs to me that I have 200GB of hard drive space sitting here doing nothing. Could I somehow use the hard drive as "virtual RAM"? Obviously it would be extremely slow since RAM is designed to be super fast by comparison, but for RAM hungry programs that take up 200MB of RAM and then just idle with it until they're closed, it would work, right? Does any programs exist that can turn hard drive space into virtual RAM? The computer is Windows 7 82.43.90.93 (talk) 18:58, 12 July 2010 (UTC)

Windows will do that automatically. When you run out of memory, it will turn part of your harddrive into swap space. You will notice it if you have a light that shows harddrive usage because you will see it blinking a lot and the computer will run very slow. -- kainaw™ 19:01, 12 July 2010 (UTC)

This is called disk paging or disk swapping, and is enabled by default in all modern general-purpose operating systems. It is more of a "backup" system to make sure your system can run even if it completely runs out of RAM, rather than a "good idea", because all types of hard disk drives are orders of magnitude slower than all types of RAM. Consequently, disk swapping has very poor performance and will remarkably slow down your programs. It should not be used "intentionally" - you should make a best-effort to keep all your memory needs smaller than your available RAM, or upgrade your RAM. Nimur (talk) 19:36, 12 July 2010 (UTC)

I would say this is a bit simplistic. Definitely you should always try to ensure you have more then enough RAM for all in use programs, having more RAM can help a lot and excessive swapping causes major slowdowns (see Thrashing (computer science) for example), particularly of course if any actively in use programs run out of RAM (Photoshop which has it's own swap system is one where you can really notice this). However modern OSes will often swap things out of RAM if it hasn't been used in a while (and other factors) to make room for more disk cache even if you have way more then sufficient RAM for all running programs. You can control this to some extent on Linux as described in our article, I think on other OSes to to some extent. Some feel Vista arguably went a bit too far in this regard. (Although I don't know if Windows 7 is really that less aggressive.) While there can clearly be no such thing as a perfect balance and for each person there will be a better balance depending on their usage pattern and of course what works well sometimes will other times be an annoyance (the OS isn't a mind reader, it has no way of knowing if that program in the background that isn't doing anything and you haven't used for 5 hours is going to be something you open 2 minutes after it swaps out the RAM it's using to disk or you'll leave it there for the next 55 hours). A lot of people seem to get very worked out about OSes (particularly Windows) doing this some even go as far as to disable the page file but if you aren't actually noticing any slow downs or other things which you don't like there's really no need to worry. Note that even on a very light loaded system with lots of RAM, most modern OSes don't recommend you disable the swapping/paging and it isn't just for emergency situations, they are designed to have it there and to use it as necessary striking whatever balance the designers have decided is best with keeping things in RAM or swapping them out. Nil Einne (talk) 00:02, 13 July 2010 (UTC)

Look under your boot drive for pagefile.sys, the virtual memory file. --Chemicalinterest (talk) 00:50, 13 July 2010 (UTC)

Hi 82, I think you're worrying about something you don't need to worry about. Window 7 is designed to use a lot of RAM when it can. RAM that is not being used is wasted RAM. It will cut back drastically if your programs need it. I have Windows 7 on a P3 with 512MB. --mboverload@ 01:46, 13 July 2010 (UTC)

Well done, didn't think that was possible. I would have used XP or Linux. Sandman30s (talk) 13:26, 13 July 2010 (UTC)

Runs like total crap, but it's due to the 8MB off-brand graphics card. --mboverload@ 07:03, 14 July 2010 (UTC)

Identifying the song used in a Youtube video with a search engine?

Does anyone know if there's a search engine to identify songs used in a Youtube video? For example, this one. --Belchman (talk) 20:11, 12 July 2010 (UTC)

There are a variety of audio search engine options, such as Shazam (service) and Midomi. Some of these are pay-services. Nimur (talk) 20:22, 12 July 2010 (UTC)

Can I whistle a tune and have it search the web for it and identify it? This is the first I've ever heard of something like that being done, but I have thought at times that that must be on the way within a few years if not sooner. Michael Hardy (talk) 02:48, 13 July 2010 (UTC)

I have heard of a service that does that about a year ago. Don't know anything more. --mboverload@ 02:57, 13 July 2010 (UTC)

I have something on my Android phone called TrackID that you can record anything through the phone and upload it for identification. Not sure if there is a computer version though. Google Goggles is the equivalent for uploading pics although there are a few others that attempt to identify pics and logos etc. Sandman30s (talk) 13:24, 13 July 2010 (UTC)

Looking for a simple BASIC language that can copy or rename files

As I have never been able to find anything that can merge two folder trees while merging folders with the same name but renaming files with the same name, I will have to write something myself.

Are there any windows BASIC languages where there are simple commands to copy a file and read and change the file names please? I need a simple non-object BASIC dialect so that I don't need to spend long learning how to use it. Thanks 92.29.123.193 (talk) 22:53, 12 July 2010 (UTC)

Batch scripting, Perl, or Visual Basic? Each has advantages and disadvantages. Extra flexibility necessarily means extra complexity. Do you need help setting up the environments for any of these tools? Nimur (talk) 23:18, 12 July 2010 (UTC)

I'm looking for something (superficially) simple that can copy a file in one line, rename a file in one line, etc. I would use GWBasic but it cannot cope with long file names, and its DOS based. Is there a Windows clone of GWBasic? Thanks 92.24.189.3 (talk) 09:16, 13 July 2010 (UTC)

The VB inside excel can do this. -- SGBailey (talk) 09:48, 13 July 2010 (UTC)

The non-Microsoft SmallBasic and BCX Basic can do it, at least, with specific command for copying files. ThinBasic and ScriptBasic could also do it but seem to be more difficult to use. There may be others. Now I have to figure out how to get them to go through a folder tree. 92.24.184.61 (talk) 17:01, 13 July 2010 (UTC)