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August 25

Revision control for OS

Are there any revision control systems aimed at (or directly integrated into) operating systems which would allow to keep track of modifications to the configuration of the OS? I understand that I could manually add configuration files to any revision control system, just wondering whether this has already been done. I'd be particularly interested in (debian) linux, but out of curiosity also interested in any other OS. bamse (talk) 08:40, 25 August 2012 (UTC)[reply]

Not quite change control, but there are Versioning file systems, which keep track of every change, and filesystems like ZFS, btrfs, and Vertitas which support snapshots. -- Finlay McWalterჷTalk 14:34, 25 August 2012 (UTC)[reply]
Not designed for the purpose, but could Subversion be suitable for the task (at least for keeping track of changes in /etc)? I know some people use Subversion as a backup tool and change control system for their /home directory (see for instance this thread). AFAIK, Subversion does a decent job with binary files, too [1]. This is just a thought, I haven't used Subversion for these purposes, and there may be downsides that I'm not aware of. --NorwegianBlue talk 11:56, 26 August 2012 (UTC)[reply]

MSIL on Wine

As far as I know, C# is compiled to MSIL, which needs the .NET framework to run on MS Windows, and Mono on Linux. So, how is it possible that AWB runs on Wine, provided that Mono is not installed? Wikipedia:AutoWikiBrowser/Mono_and_Wine --151.75.107.190 (talk) 14:18, 25 August 2012 (UTC)[reply]

Wikipedia:AutoWikiBrowser/Mono and Wine#Wine says that, to run it in Wine, winetricks has to download and install the .NET2 runtime from Microsoft. -- Finlay McWalterჷTalk 14:29, 25 August 2012 (UTC)[reply]
Okay, thank you. --151.75.107.190 (talk) 14:37, 25 August 2012 (UTC)[reply]

S.M.A.R.T. Warning message

I noticed a warning message in the disk utility of my Linux server recently. See screenshot. Is this an indication that I should replace the disk, or is it a more benign warning message? Thanks, --NorwegianBlue talk 15:18, 25 August 2012 (UTC)[reply]

.

I would certainly want to have everything on that disk backed up properly. If the disk is mission-critical (that is, if you'd suffer significantly from the downtime associated with replacing it and restoring that backup) then I'd replace it now. If not, you may wish to risk keeping using the disk. That number should certainly be zero, but its being nonzero isn't evidence enough to assume impending failure. If the number increases, that's likely evidence the disk is dirty, scratched, or contaminated, and I'd replace it then. -- Finlay McWalterჷTalk 15:27, 25 August 2012 (UTC)[reply]
Here's the meaning of those four numbers at the bottom:
  • "Normalized": A manufacturer-defined measure of healthiness where 100 (sometimes 200) is normal and smaller values are worse.
  • "Worst": The lowest normalized value this parameter has ever had on this drive.
  • "Threshold": The normalized value at which the drive should probably be replaced (according to the manufacturer).
  • "Value": More detailed information; in this case, the actual count of reallocated sectors.
So according to the scale set by the drive manufacturer, 5 reallocated sectors is nothing to worry about. -- BenRG (talk) 20:02, 25 August 2012 (UTC)[reply]
There was a Google study a while back showing that SMART-reported errors of any sort were highly correlated with impending drive failure. If it were my drive I'd take it out of service immediately, rather than backing it up and waiting for it to fail. 69.228.170.132 (talk) 02:25, 26 August 2012 (UTC)[reply]
It's not an error. The health parameter is at 100%. I don't know why this particular SMART monitor treats any nonzero raw value for this parameter as worthy of a message at all. Most wouldn't. There's a green circle next to the message, which I suppose is meant to mean that it's purely informational. -- BenRG (talk) 04:52, 26 August 2012 (UTC)[reply]
Thanks everyone! I experienced a similar situation with the same computer a year ago. It then had three disks, which all were new. When I returned from summer holidays, all three disks had SMART-reported error messages similar to the one showed here. I then replaced all three disks. Given the time of year that these problems have occurred, I wonder if it may have been caused by transients on the power grid during thunderstorms. All the circles were green then, too. The message next to the circle when absolutely everything is ok, is "Disk is healthy". I also noticed now, that there is a mouseover message associated with the Reallocated Sector Count warning, that says:
Type: Failure is a sign of imminent failure (Pre-Fail).
Updates: Every time data is collected (Online)
Raw: 0x050000000000
I'm not really sure what to make of that information, i.e. if it is saying that there actually is a failure condition now, or if it is saying what the interpretation would be if there were a failure condition. To be on the safe side, my immediate action will be to switch the roles of the two 1.5 TB disks on the system (the problem disk holds the /home partition, the other 1.5 TB disk mirrors /home, rsynced every night). --NorwegianBlue talk 10:32, 26 August 2012 (UTC)[reply]
It's saying what the interpretation would be if there were a failure condition (i.e., if the normalized value dropped below 36). This interpretation is also chosen by the drive manufacturer. There's some information here.
I'm kind of depressed that Google's data is convincing people to send perfectly good drives to the dump out of fear of random failure (most of their drives with a few reallocation events didn't fail). But I guess it's cheaper than RAID mirroring if downtime is expensive but not too expensive. -- BenRG (talk) 20:04, 26 August 2012 (UTC)[reply]
From the Google study "Failure Trends in a Large Disk Drive Population": "As with scan errors, the presence of reallocations seems to have a consistent impact on AFR for all age groups (Figure 7), even if slightly less pronounced. Drives with one or more reallocations do fail more often than those with none. The average impact on AFR appears to be between a factor of 3-6x." AFR is Annualised Failure Rate. So it does appear that this is indicating a higher than normal liklihood of disk failure. --Phil Holmes (talk) 10:00, 26 August 2012 (UTC)[reply]
Thanks! Googling your quote, I found the study here. --NorwegianBlue talk 10:46, 26 August 2012 (UTC)[reply]
Some of those graphs are unreadable. A readable PDF version is here. -- BenRG (talk) 20:04, 26 August 2012 (UTC)[reply]
Excellent, thanks! --NorwegianBlue talk 21:20, 26 August 2012 (UTC)[reply]

Programming for mobile/embedded devices

How would one compile a program for a mobile/embedded device? — Preceding unsigned comment added by YoungAspie (talk • contribs) 17:29, 25 August 2012 (UTC)[reply]

You would compile it like any other program, except that the target output would be for a different CPU. See Cross compiler RudolfRed (talk) 17:33, 25 August 2012 (UTC)[reply]

Then how would one transfer the compiled code to the embedded device? — Preceding unsigned comment added by YoungAspie (talk • contribs) 17:36, 25 August 2012 (UTC)[reply]

It depends on the device. The iPhone for example is updated over USB. Other devices might use serial port or JTAG. RudolfRed (talk) 20:56, 25 August 2012 (UTC)[reply]
When my job was programming embedded devices (1981–4), we used a "burner" to program a read-only memory chip. I imagine that times have changed. —Tamfang (talk) 00:24, 26 August 2012 (UTC)[reply]
There are many standard methods to communicate to an embedded device. You are undoubtedly familiar with the USB protocol; many modern devices have hardware support for USB, so you can program and debug using USB. Another common standard is JTAG, which specifies certain low-level communication methods and defines a hardware interface. JTAG is supported on many embedded devices, even when USB is not. Other embedded computers use less common protocols; or they use customized technology created by the manufacturer or designer.
To run a program on an embedded device, you can either boot directly to the program; or you can run a (simple) operating system on the device. To boot directly, your program must know intricate details of the hardware, and manage the low-level device bring-up. For this reason, many embedded systems come with a ready-to-use operating system. The operating system will specify how to load and run external programs. Many new systems use full-fledged file systems that are compatible with desktop computers. Often, an embedded computer can attach an SD card and treat it as a "hard disk" with a standard file system; the embedded operating system loads the program file and executes its main function. Other embedded devices can be programmed over JTAG, and the program may reside in RAM only until the next reboot; or can be stored to a nonvolatile memory. Nimur (talk) 17:39, 26 August 2012 (UTC)[reply]

Legality of redistributing software available for free download

What is the legality of redistributing software that's available for free download, without permission from the copyright holder? Specifically, several companies make available software programs as a large (>2 GB) DVD images for free download. I would like to republish the ISOs on my web site as BitTorrent links, to help those with unstable Internet connections or unstable computers. I understand that copyright prohibits copying and redistribution, but does it make a difference that the copyright holder is not trying to copy-restrict the ISOs themselves, instead requiring an activation key to use the software? 63.152.89.215 (talk) 21:01, 25 August 2012 (UTC)[reply]

You appear to be asking for legal advice. We do not answer such questions. Sorry. AndyTheGrump (talk) 21:11, 25 August 2012 (UTC)[reply]
Though the general answer is pretty straightforward, and is not legal advice. --Mr.98 (talk) 23:09, 25 August 2012 (UTC)[reply]
Check the license distributed with the software. It will tell you whether redistribution is allowed. Just because something is provided for no charge (gratis) does not mean it is free for you to redistribute — it does not mean that copyright does not apply, it does not mean that your own redistribution of it would not be a copyright violation. --Mr.98 (talk) 23:08, 25 August 2012 (UTC)[reply]


August 26

Counter Strike Global Off.

I am having major lag spikes in the game Counter Strike Global Off., does anyone know how to fix the game (IT IS THE GAME NOT MY INTERNET). — Preceding unsigned comment added by 76.16.47.115 (talk) 02:57, 26 August 2012 (UTC)[reply]

Have you tried a reboot ? StuRat (talk) 04:43, 26 August 2012 (UTC)[reply]

Samsung Series 5 17.3 inch laptop

Anyone here have this particular model laptop? I need to know if I'm the only one experiencing problems with the touchpad not being sensitive enough so I can know whether to return & exchange it for another one of the same model or get a different one altogether. 70.52.79.25 (talk) 08:55, 26 August 2012 (UTC)[reply]

Fast output of plots in MATLAB

Hi,

Does anyone know of a quick way to save a MATLAB plot (to png) without actually having to call up a figure? I need to process a large number of frames (1000s) to make up an animation and at the moment I'm creating a figure and then using print(gcf,...) but this is pretty slow... Thanks, --Fir0002 11:26, 26 August 2012 (UTC)[reply]

Per the documentation, specify the figure property 'Visible', off. Also, consider re-using the same figure handle, when appropriate, instead of creating a new figure. You can update the figure contents without creating a new figure. Nimur (talk) 17:28, 26 August 2012 (UTC)[reply]
Thanks for that - I did try updating the figure contents each time, but MATLAB was complaining with:
Warning: Color Data is not set for Interpolated shading
> In C:\Program Files\MATLAB\R2009b\toolbox\matlab\graphics\hardcopy.p>hardcopy at 21
In graphics\private\render at 143
In print at 277
In shifting_fft_plots at 102
In shifting_psdd_full_field at 94
(each frame is a pcolor plot and I want the shading set to interpolated -> and if I set shading to interp outside the loop it doesn't carry through...)
It works despite the warning so I think I'll just ignore it ;) --Fir0002 06:02, 27 August 2012 (UTC)[reply]
That warning means you did not specify color data for the patch using the FaceVertexCData property. Default colors are being used. Nimur (talk) 18:14, 27 August 2012 (UTC)[reply]
Hmm it actually doesn't seem to be that efficient a method at all over the long term as it get slower each iteration - over the first 50 iterations time linearly increased from ~0.5 seconds to ~1.3 seconds. Compare this with calling up a figure each time the times remain at around 0.7 seconds... --Fir0002 02:43, 30 August 2012 (UTC)[reply]
So yes, it seems that the best method is to call up a figure each time but with the visible off figure property (each iteration is ~0.55s) --Fir0002 09:19, 30 August 2012 (UTC)[reply]

Location based reminders in Android

I need to accept a location from the user, compare it with the current location (using GPS) and give an alarm to the user if it matches. I'm new to android, but I do know that I need to use LocationManager and AlarmServices. Can someone please give me an outline of how to go about it and especially how to integrate alarms into GPS. I'll be most grateful for any help provided. Thank you very much. :) Zebec 15:26, 26 August 2012 (UTC)[reply]

As I understand it, you can do this with just the LocationManager's addProximityAlert call, to which you provide the coordinates of interest and a necessary fudge radius, and it calls you back when the phone is near that place. A simple example of someone writing what you're looking for is here. I don't see why, just to do that, you'd need AlarmManager as well - LocationManager already polls the GPS for you. Note that AlarmManager isn't for user notifications (it's a poor name choice - it should be called ScheduledCallbackManager or something). Notifying the user something has happened is done with Alerts, Toasts, and Notifications (tutorial). -- Finlay McWalterჷTalk 15:58, 26 August 2012 (UTC)[reply]
This sounds like something you could use Tasker for. - Cucumber Mike (talk) 19:13, 26 August 2012 (UTC)[reply]

Does Playbook's security swipe really work?

Dear Wikipedians:

I have just performed a security swipe on my Playbook using its "security swipe" feature under the security section of its settings pages. However, the length of time between when I tapped "security wipe" button and when I got the new splash screen asking me to set up my "new" playbook is such that I do not believe my playbook has had the time to go through all the bytes in its 16 GB of permanent memory and reset each one of them to 0x00. I am wondering if any of you could help enlighten me to the true nature of Playbook's security wipe, whether it really does its job, and what else I can do to make sure all my data on my Playbook is fully erased and could not be recovered, even with forensic computer data retrieval expertise, in case Playbook's in-built security wipe does not do the full job.

Thanks a million,

76.68.41.45 (talk) 15:41, 26 August 2012 (UTC)[reply]

If I understand you correctly, you have a BlackBerry PlayBook tablet with 16Gb of on-board NAND flash memory, and you're using the security wipe feature to erase the portion of that which stores user files and data (that also stores the Blackberry OS and built-in applications). One thing to note about flash memory is that it isn't erased by writing bytes to it (it's not like a hard disk) - the memory is organised into larger blocks, which are erased by issuing a block-erase command (which simultaneously wipes all the bytes in that block). To know how long that will take, and to know whether the specific flash part found in the Playbook can concurrently erase blocks, we'd need to figure out what flash part it has, so I can read the datasheet. If anyone can find a good high-res image of a deconstructed Playbook, so we can read the part numbers, that would help a lot. -- Finlay McWalterჷTalk 16:16, 26 August 2012 (UTC)[reply]
Hmm, I'm quite encouraged. The part is a Sandisk SDIN 5C2-16G device. I found the product information sheet for that here. Talking about the "secure erase" command, the datasheet says "This new command meets high security application requirements (e,g, those used by military and government customers) that once data has been erased, it can no longer be retrieved from the device." As RIM sells a lot into US Government circles, I think they and SanDisk really will be standing behind that claim. But I can't find a programming/timing manual for that part, which would tell me how long the erase should take. Preliminarily, it sounds like they do take properly secure erasure seriously. -- Finlay McWalterჷTalk 16:29, 26 August 2012 (UTC)[reply]
That sheet does say the erasure is done in "erase groups", and has a place where the size of a group is specified (up to multiples of 8 GB, it seems). I still can't find a real timing diagram, but that too suggests the erasure would be done in one or a handful of operations (depending on how they lay out their use of the flash memory), which you would expect to be a second or two. But an important caveat: this shows Blackberry can do this; it doesn't show they do, and there's little way to find out what they do (bar doing real forensics yourself). -- Finlay McWalterჷTalk 16:44, 26 August 2012 (UTC)[reply]

I read the question as "Playboy's security swipe" and wondered that there's now such a convenient feature available... JIP | Talk 18:16, 26 August 2012 (UTC)[reply]

Erasure of a filesystem of any size could be done in a split second, if the filesystem was encrypted and the system simply forgets the encryption key. I recall iOS doing such a thing when told to perform a secure wipe, but apparently the playbook doesn't encrypt its entire filesystem[1] Unilynx (talk) 19:20, 26 August 2012 (UTC)[reply]

Question about mounting hard disks on Fedora 17

After I had upgraded to Fedora 17, I found that when I first booted it up, everything worked, but when I shut the computer down and booted it up again, Fedora went to emergency mode before I could even log in, asking me for the root password, and when I gave it, dropped me to a text-only shell. In panic that I had broken the system, I reinstalled Fedora 17 and everything worked, but after I rebooted, the same problem appeared again.

I decided to google "Fedora emergency mode" and found the cause of the problem. I have additional Lacie external hard drives that I use for back-up, but I keep them powered down when they're not in use. I have written entries for them in /etc/fstab so that I can manually mount and unmount them with a single command. Now what was happening was that on boot-up, Fedora found these entries in /etc/fstab and tried to mount them, but failed because the disks were powered off. This caused Fedora to think "Oh no! Mounting file systems has failed! Let's stop right here and inform the user that something has gone horribly wrong!", which I took as a corrupted system.

Is there any way to write the entries to /etc/fstab telling the computer that the drives should not be mounted on boot-up, they'll be mounted when I say so? JIP | Talk 18:29, 26 August 2012 (UTC)[reply]

Stop reinstalling. :p ¦ Reisio (talk) 20:11, 26 August 2012 (UTC)[reply]
Use the noauto option in fstab (see man fstab). Make sure to mount by UUID and not by device, as rearranging your usb devices (or just plugging in a little flash drive) can cause Linux to assign disks to different devices, messing up your mount scheme. -- Finlay McWalterჷTalk 18:44, 26 August 2012 (UTC)[reply]
Thanks, that worked. I wrote the same entries into /etc/fstab but this time with the option noauto, and the system was able to boot up normally. JIP | Talk 19:16, 26 August 2012 (UTC)[reply]
I can't speak for Fedora, but on Ubuntu I don't use fstab to mount usb disks. Instead I let udev and Nautilus automatically mount them (as described here). That way they end up at /media/<partitionlabel>, where <partitionlabel> can be set (if you're smart, uniquely) as described here. -- Finlay McWalterჷTalk 19:08, 26 August 2012 (UTC)[reply]

Move from hotmail to Outlook

What is the end game plan for @live.co.uk email accounts now that Outlook is being rolled out to replace Hotmail? Will they still exists or will they be migrated to Outlook or what? Thanks. 92.6.144.109 (talk) 18:58, 26 August 2012 (UTC)[reply]

Your email address stays the same (still @live or @hotmail or whatever) and you still log in the same way you did before, with the same password. The only difference is the site you end up at is branded Outlook and has the Outlook interface. So it's a pretty seamless transition, really. -- Finlay McWalterჷTalk 19:04, 26 August 2012 (UTC)[reply]

Transfer entire Linux system to a new hard drive?

I just bought a new 2 terabyte hard drive, which I'd like to transfer my entire existing Fedora 17 Linux system to. The current system is on two physical drives with a total of 4 partitions (plus a swap partition), about 800 gigabytes in total. This is becoming too small for me. How can I transfer my entire Linux system to the new hard drive? I could just plug it in, partition it with GPartEd and format all the partitions, and copy all the files across, but how do I get the disk labels right in /etc/fstab on the new disk, and how do I create a bootloader? Would it be easier to simply do a full install of Fedora 17 on the new drive, and then copy all my old files across, either from the original drives or the back-ups I've been creating on my external Lacie hard disks? Can I just back-up the entire root (/) partition to the Lacie drive and restore it to the new disk, but with keeping /etc/fstab intact? It's the exact same version of the operating system, so that shouldn't pose a problem. JIP | Talk 19:58, 26 August 2012 (UTC)[reply]

Taking a simpler case, say I had a single drive /dev/sda (from which my system booted) and I bought a bigger drive to which I wanted to copy everything, and boot from that. Say I plugged it in and it became /dev/sdb. I'd boot from a livecd, then I'd
 sudo dd if=/dev/sda of=/dev/sdb
Be very sure of the ordering: if is the input, of is the output; if you get it wrong, you copy blankness over your good disk - there's no going back from that. That'll grind for a few hours, and at the end of it the start of /dev/sdb will be a bit-for-bit copy of the old disk. Once that's done you can remove the old disk, and the big new one will become the new sda. The system should then boot identically from that, as if it was the old disk. Then I'd boot to a livecd again and use gparted to resize the partitions to take up the space. -- Finlay McWalterჷTalk 20:08, 26 August 2012 (UTC)[reply]
I'm aware of what dd does, but I don't think this will help me, because my old system consists of two physical drives. These appear on Linux as /dev/sda and /dev/sdb. I don't think it's possible to use dd to transfer both of them to the same new drive. JIP | Talk 20:15, 26 August 2012 (UTC)[reply]
Weeelll: Once you've copied the first lot, use gparted to make two new partitions (of the appropriate size) on the 2TB disk. Then dd the contents of the old partitions (say /dev/sdc1, /dev/sdc2) to their counterparts on the 2TB disk (say /dev/sda4, /dev/sda5). I think that'll work, but I've not done anything like that for a while. If it doesn't, well, you should have rsynced :) -- Finlay McWalterჷTalk 20:25, 26 August 2012 (UTC)[reply]
If you do this, I think you'd need to change the UUIDs and partition labels of the newly created partitions to match the old ones, so the partition table is coherent. -- Finlay McWalterჷTalk 20:39, 26 August 2012 (UTC)[reply]
But you've got two disks, each with two partitions. You can certainly copy individual partitions to specific places using dd, but you need to use dd's offset parameter, and (while I have done it) I'd not recommend someone unfamiliar with dd and raw disk addressing do that (again because it's a sledgehammer). If the partitions on old_disk2 are just regular files (music, videos, etc.) I'd personally want to end up with just the existing (resized) partitions on the 2TB disk, and I'd copy (rsync) the regular files to ordinary folders there. But then I personally dislike partitioning more than is absolutely necessary, so others may advise you on keeping the partitions and copying them with something I'm ignorant of. -- Finlay McWalterჷTalk 20:15, 26 August 2012 (UTC)[reply]
What I usually do is use rsync -av /mnt/old/ /mnt/new/ (which can be resumed [by running the same command again] if interrupted) to copy the data from a liveOS. You can fix /etc/fstab with the information from blkid run as root (using UUID or LABEL values instead of /dev/foo is a good idea), and fix GRUB with grub-install /dev/sdX (where X is the 2TB device name letter). You might also want to reorder the drives (by cable connections) to have your 2TB be the first device before reinstalling GRUB, if you haven't already. If you were changing more than just the hard disk (migrating the system to an entirely different computer, for example), you might also need to alter your kernel/modules for proper driver support. ¦ Reisio (talk) 20:23, 26 August 2012 (UTC)[reply]

rsync --delete question

I've been using rsync to create back-ups of my system to my external Lacie hard disks. The man page tells me that rsync --delete will delete all files and directories on the destination that are not found on the source. But I found out that it only works for the top level of the source and destination directories. Any files and folders in subfolders of the destination that are not found in the respective subfolders of the source are left untouched. How can I make the --delete option work recursively? JIP | Talk 20:03, 26 August 2012 (UTC)[reply]

You'll need to tell us all the options you're passing to rsync. -- Finlay McWalterჷTalk 20:09, 26 August 2012 (UTC)[reply]
rsync -rv --delete . /lacie (where /lacie is the mount point of my external hard drive). JIP | Talk 20:15, 26 August 2012 (UTC)[reply]
For a backup I do rsync -av --delete which works fine, and certainly deletes files as I'd expect. -a implies a bunch of useful flags (copies perms, owner and group, etc.). You've not got FAT32 or NTFS on the Lacie, have you? -- Finlay McWalterჷTalk 20:29, 26 August 2012 (UTC)[reply]
rsync -av --delete seems to work fine. But after I have done it once, I want subsequent calls to skip files that are already present on the destination and haven't been changed on the source. Otherwise it is going to take me hours each time, with all my about one hundred thousand digital photographs stored on both my internal hard disk and the Lacie disks. And no, the Lacie disks are not FAT32 or NTFS, they're ext3. JIP | Talk 18:06, 27 August 2012 (UTC)[reply]
Yes, -a does that. It reads all the directories, stats all the files, compares timestamps, and does the obvious things. 69.228.170.132 (talk) 18:10, 27 August 2012 (UTC)[reply]

Java Book

I've just finished learning the beginnings of Java with "Java How to Program" by Deitel and Deitel. Can anyone suggest a suitable second book to advance my studies? Thanks. 92.6.144.109 (talk) 20:27, 26 August 2012 (UTC)[reply]

Effective Java by Joshua Bloch. -- Finlay McWalterჷTalk


Please refer JAVA 2:The Complete Reference By Herbert Schieldt published by McGrawhill.This is a wonderful book on Object Oriented Concept using Java 2. Also it teaches advance techniques in Java.

I don't know anything about this book, but Schildt's books have a terrible reputation in general. I would avoid anything with his name on it. -- BenRG (talk) 19:50, 31 August 2012 (UTC)[reply]

HTTP space between headers and body..

How do I know where the headers end and where the content begins if I'm parsing raw http? 190.158.212.204 (talk) 21:15, 26 August 2012 (UTC)[reply]

Formally, two consecutive <CR><LF> pairs. Informally, you might occasionally see clients that only send the <LF>s. -- Finlay McWalterჷTalk 22:29, 26 August 2012 (UTC)[reply]


August 27

Difficulty finding page related to "Order of Operations" in Mathematics.

"Order of Operations" is such a simple process, we all learn it in grade school. I needed to use the term in an email, and it took me over one-half hour to find it!

Everything that was being returbed by your search engine were articles at the college level and beyond.

Maybe you need a "Kidapedia"? — Preceding unsigned comment added by Drexpert007 (talk • contribs) 00:32, 27 August 2012 (UTC)[reply]

Have you tried the Simple English Wikipedia? simple:Order of operations -- Dismas|(talk) 00:42, 27 August 2012 (UTC)[reply]
The article is Order of operations. Wikipedia normally does not capitalize words other than the first word in article titles, unless the words are proper names or the like. See WP:TITLEFORMAT. 69.228.170.132 (talk) 18:03, 27 August 2012 (UTC)[reply]

how long does it take to overwrite hard drive using system recovery disc

Let me clarify a few details:

- I've had the computer for a couple of weeks
- I haven't done much with it other than log in to email and forum accounts via web browsing.
- The hard drive is 1 TB in size (854GB in free space actually available). I plan on returning it Monday, so I just need to know if this will take a long time (as in hours on end) or if it's a brief and reasonable time (as in under an hour) 70.52.79.25 (talk) 08:15, 27 August 2012 (UTC)[reply]
To clarify: Do you want to overwrite every bit on the disk to blank it out, including the empty portion ? I assume you want to do this for security reasons, before returning it ? Technically, you shouldn't need to blank out any any unallocated sectors, although you would need to blank out the empty portion of allocated partitions, as it may have had data in them which was "deleted", which just means the index entry is removed, and the data is left in place.
To answer, we would need to know the hard disk model number, so we can find it's write speed. StuRat (talk) 09:34, 27 August 2012 (UTC)[reply]
Don't know the model number, but I know the read and write speed is 5400rpm. --70.52.79.25 (talk) 15:21, 27 August 2012 (UTC)[reply]
It will take several hours at least to overwrite the whole disk surface. Overwriting only used portions would take less than an hour, but that won't necessarily overwrite all personal information, and I doubt the recovery disk has it as an option anyway. If it's a Windows machine and you want to minimize downtime, you can install TrueCrypt and set it to encrypt the system drive. This takes hours but the system is usable during that time. Then erasing the drive is instantaneous: just forget the passphrase. -- BenRG (talk) 16:45, 27 August 2012 (UTC)[reply]
If it's a recent SATA drive it likely supports a "secure erase" operation (we could use an article about that). You should use that in preference to a software program if you can do so conveniently, but either way, yes, wiping a 1TB disk is likely to take a few hours. A rough guess for an internal SATA might be 100MB/sec which is 10000 seconds or around 3 hours. If it's a USB2 disk it will be more like 20MB/sec, or about 15 hours. In principle maybe you could get away with wiping just part of the drive, but if you had anything sensitive on the drive it's safer to wipe everything. 69.228.170.132 (talk) 18:08, 27 August 2012 (UTC)[reply]

Django simple button + field + saving

I know python and a little bit about django (at least, enough about urls.py and views.py to copy and paste a working example.) I'd like to have a simple function:

Button, when pressed, it processed the text obtained from a text field and does two thing: shows it on screen and saves it to a file (append to text file or SQLite, whatever is easier). How can I do that? Comploose (talk) 17:27, 27 August 2012 (UTC)[reply]

I don't know enough Django to do it justice, but I can give a trivial example in Bottle, which should at least give you the conceptual idea of what to do.
#!/usr/bin/python
import os.path
from bottle import get, post, request, run, Bottle 

NAMEFILE = 'names.txt'
app = Bottle()

def generate_page(msg=None):
    if msg:
        html = '<div style="color:red;">'+msg+'</div>'
    else:
        html = ""

    if os.path.exists(NAMEFILE):
        f = open(NAMEFILE,'r')
        for name in f.readlines():
            html += name.strip() + '<br>'
            f.close()

    return html + '''<form method="POST" action="/">
                       <input name="name" type="text">
                       <input type="submit" value="add name">
                     </form>'''

@app.route('/')
def page():
    return generate_page()

@app.post('/') 
def page_submit():
    name = request.forms.get('name')
    if len(name)>0:
        if os.path.exists(NAMEFILE):
            f = open(NAMEFILE,'a')
        else:
            f = open(NAMEFILE,'w')
        f.write(name+'\n')
        f.close()
        return generate_page('added:'+name)
    else:
        return generate_page()

run(app, host='localhost', port=8080)
That's pretty minimal, and not an example of good practice, but hopefully it's instructive nevertheless. -- Finlay McWalterჷTalk 19:43, 27 August 2012 (UTC)[reply]
Ooooh. Thanks for the answer. I thought that could be done in kind of three lines of code, but no, I'll have to invest more time to get it. Comploose (talk) 22:23, 27 August 2012 (UTC)[reply]

Has anyone got The Ur-Quan Masters to work?

Has anyone ever got The Ur-Quan Masters to actually work on a Linux system? I installed the game on my fresh Fedora 17 system, eager to play it, because I played the original Star Control intensively on my old Amiga 500, but the sequel never appeared on the Amiga. uqm --version reports I have version 0.7.0. When I start it, I get as far as the main menu, and when I select "New game", I get a screen saying "IGL - Interstellar Frungy League presents", after which the program crashes. Is there a working version available anywhere? JIP | Talk 18:54, 27 August 2012 (UTC)[reply]

Start it from a terminal and observe the output when it crashes. ¦ Reisio (talk) 17:42, 28 August 2012 (UTC)[reply]
OK, I tried that. It just says "Segmentation fault (core dumped)". JIP | Talk 18:49, 28 August 2012 (UTC)[reply]

Facebook question

What is the max size of a file you can attach to a personal message on facebook? — Preceding unsigned comment added by KobiNew (talk • contribs) 19:37, 27 August 2012 (UTC)[reply]

August 28

Options request by firefox.

Currently this is giving me problems, when I try submit stuff, (From an usefull userscript for a page), these servers are 'silly' and can't reply correctly to an OPTIONS request, I don't have any control over the servers, but I really want to fix this problem...

Is there anyway.. to disable options request, or to enable Cross-Domain Ajax just for one domain in firefox? , or at least allow cross domain request globally? Thanks.. 190.158.212.204 (talk) 00:19, 28 August 2012 (UTC) Also.. is there any way to add user quota in a page from google chrome? It can be user side fix. I'm getting QUOTA_EXCEEDED_ERR: DOM Exception 22. 190.158.212.204 (talk) 00:35, 28 August 2012 (UTC)[reply]

Is a GPU Required in a Computer?

When a computer displays a graphic on the screen, does it have to use a GPU? Can the CPU communicate directly with a monitor? I am aware some modern CPUs have GPU circuitry built in, but for the sake of simplicity, please assume I am referring to CPUs manufactured before 2010. If they always use the GPU, how much do they rely on it for simple tasks like composing e-mails and browsing web sites? — Preceding unsigned comment added by 50.95.200.141 (talk) 05:16, 28 August 2012 (UTC)[reply]

At the very least, you need a PHY that operates a standard display protocol - like VGA or HDMI. Usually, there's a little hardware to control the PHY, and a video frame buffer. Without that hardware, you can't get a signal to a monitor. One could call that hardware a GPU, but in modern terminology, a GPU also usually supports certain specific mathematical operations: "T&L", often providing hardware support to a standard API like OpenGL. Those features are't required to put pixels on a screen; but this hardware is so commonplace that modern operating systems make use of it even during normal use, like displaying windows, editing text, and browsing the web. Nimur (talk) 05:32, 28 August 2012 (UTC)[reply]
Transform & lighting was a fairly late addition to consumer GPUs, which is why it was advertised more prominently as something they support—the rest was taken for granted. The earliest GPUs just did bulk pixel-moving operations (blitting) faster than the CPU could (although they were called blitters then, not GPUs). The first 3D GPUs rendered shaded polygons but didn't work out the vertex locations or colors (that's the transform and lighting part). As long as the polygon count was small T&L could be done on the CPU, since it's per-vertex rather than per-pixel. -- BenRG (talk) 17:38, 29 August 2012 (UTC)[reply]

Thanks for the reply. So, I assume, then, that disabling the GPU on most modern systems would render the monitor nonoperational, because the PHY chip and the framebuffer are build into the GPU? — Preceding unsigned comment added by 50.95.200.141 (talk) 06:41, 28 August 2012 (UTC)[reply]

That's usually where the functionality is built in to. Of course, it can be elsewhere: on the CPU, or on the CPU's chipset or main logic board controller; there may be more than one unit, digitally switched to drive one or more connector sockets. On many PCs, the main GPU is started late in the boot, so the very first signals you see on power-up are sourced by the simple built-in graphics system; once the necessary software has loaded, the operating system initializes the main GPU and switches the display signal to source from there. On embedded computers, or custom-designed systems, almost anything is possible. Nimur (talk) 15:55, 28 August 2012 (UTC)[reply]
A computer can well do without graphics circuitry of its own, it can have, say, a serial terminal attached to it. Early computers worked this way which I think is responsible for the rise of editors like vi, as you can't easily draw windows, menus and stuff over a 300 baud line. Уга-уга12 (talk) 11:49, 28 August 2012 (UTC)[reply]

Going back to earlier personal computers, the Apple II, for example, did not have a dedicated GPU. Tarcil (talk) 17:29, 28 August 2012 (UTC)[reply]
Apple II had an analog RF modulator that output NTSC signal. It is usually called a "video controller unit" or a "modulator," not a "graphics processor." It was, as I mentioned above, just a PHY, and did not include hardware to accelerate mathematical operations like matrix transforms for 3D projection or texture scaling. Apple II did include a hardware and ROM-supported text mode. Nimur (talk) 18:13, 28 August 2012 (UTC)[reply]
My understanding of the term "GPU" has always been that it's a specialized processor that writes to the frame buffer, and has nothing to do with the circuitry that reads the frame buffer and sends that data to the monitor. The GPU article seems to agree. So the answer is simply no. Even on a modern graphics card the GPU doesn't communicate with the monitor. You could remove the GPU from a modern card and still use it, if the drivers and the card wiring supported that.
The part that reads the frame buffer is called a RAMDAC, though I guess that term isn't appropriate any more when the output is digital (DVI/DisplayPort/HDMI). -- BenRG (talk) 17:12, 29 August 2012 (UTC)[reply]
In the case of digital signaling, like HDMI and DVI, the more generic term, "PHY", is used. A RAMDAC is an implementation of a specific type of PHY for analog protocols (often VGA). Nimur (talk) 18:38, 29 August 2012 (UTC)[reply]
I've never heard "PHY" used in this way and googling [ramdac "phy"] doesn't turn up anything. I don't think it makes sense as a name, either, since the video output circuitry does a lot more than just send bytes over the wire, including colorspace conversion, hardware overlays and hardware cursors, and character generation. I'm not sure that all of this is covered by RAMDAC either, though.
Actually, according to the framebuffer article, "framebuffer" is a collective term for all of this circuitry. I'd always thought of it as just the VRAM. -- BenRG (talk) 20:54, 29 August 2012 (UTC)[reply]
Terminology isn't nearly as standardized for engineering subsystems as it is for consumer-facing end-products. So, when you go down to a retail electronics store and buy a "graphics card," it's pretty clear that you mean "a GPU that supports (commonly-used graphics programming API A, B, and C version X); a connector-socket or sockets that connects to (recent modern video display standard D, E, and F version Y);" and so on. When you're looking across different types of computers, or across many generations spanning decades of engineering, the terminology is a lot less interchangeable. I used to work on at a silicon company that built a small camera processor (you might call it a "Digital Signal Processor"). For some customers, who wanted fancy animated graphical user-interfaces on their cameras, we used the camera's input pixel pipeline hardware to implement polygon rendering, and we used the DMAs to blit and scale and interpolate. By short-circuiting the hardware input from the sensor interface, we could even plug "textures" through the pipe. So, our chip and our operating system supported (some) 3D graphics, and a lot of 2D graphics operations. Nobody called it a "GPU" - we called it awful. And our "framebuffer" was just regular RAM; and our PHY was called "VOPU" for "video output unit." Almost nobody knew or used these acronyms, because we never marketed them. Anyway, my point is, there are "GPU"s - standard chips from NVIDIA and ATI and Matrox and Intel that support commonly-understood interfaces; and then there are "GPUs" - anything that resembles a "unit" that sort of "processes" "graphics." You can build any computer you want - with any kind of graphics processing capability - if you can resource the engineering talent and money to fab silicon. Otherwise, you have to take the feature-set that's available on the open market. Nimur (talk) 16:36, 30 August 2012 (UTC)[reply]
The component that sends the data to the monitor is the TMDS transmitter (for DVI connections). A RAMDAC is used for VGA output. The GPU is used as a graphics accelerator and is used by the CPU to offload some of the graphics-processing burden. The CPU can manipulate graphics, but is less efficient at doing so. Today, both the RAMDAC and TMDS transmitter are usually integrated onto the same die as the GPU. But many card manufacturers add on a standalone TMDS transmitter to the card to support dual DVI outputs.—Best Dog Ever (talk) 05:39, 30 August 2012 (UTC)[reply]

Play Ogg Theora and Vorbis files directly on iPad

Is there any app or extension which can play OGG files directly (without conversion) on iPad — Preceding unsigned comment added by Write English in Cyrillic (talk • contribs) 06:03, 28 August 2012 (UTC)[reply] 

Write English in Cyrillic (talk) 06:03, 28 August 2012 (UTC)[reply]
You can use VLC on a jailbroken iPad, but it is no longer available from the Apple App Store. -- Finlay McWalterჷTalk 11:23, 28 August 2012 (UTC)[reply]

DNS not working, but only for browsers

I have a laptop running Windows 7 x64 which had some kind of Internet monitoring/filtering software on it called "Action Alert". I noticed that this software was chewing up a lot of CPU, so I uninstalled it via the "Uninstall Action Alert" in the Windows Start Menu. Immediately after this, I noticed that all of the web browsers on the laptop (IE, Firefox and Chrome) are unable to resolve any host names. I tried googling the issues and found this forum post, which describes exactly the same problem I am having, and provides additional technical details. To the best of my ability I ran the same tests as mentioned in that post, and confirmed that Ping still works, and typing an IP address directly in the address bar also works. Other computers on the network have no problems, so I know it's not a general network issue. I am not using any proxies, either. I have never modified Windows Firewall, so it is set to whatever default settings it came with.

What can I do to get the browsers working again? 98.103.60.35 (talk) 12:50, 28 August 2012 (UTC)[reply]

I would also check that nslookup www.google.com works. Have you checked your HOSTS file? Also it's possible the firewall has been set to prevent HTTP traffic - have you checked that?--Phil Holmes (talk) 15:00, 28 August 2012 (UTC)[reply]
Sorry for a lame suggestion, but I would run a malware detector, on the theory that "Action Alert" is a redirector of some sort that has installed something that petulantly blocks browser requests that don't go through "Action Alert". Tarcil (talk) 17:21, 28 August 2012 (UTC)[reply]

Googling vs. typing URLs

Is there any data on how often people Google the keywords they're looking for vs. entering a URL in their browser with the hope that it's what they are looking for? I'm thinking along the lines of someone looking for the Transformers movie — they could Google "transformers", where the movie (or its sequel) is the third GHit; or they could type "transformers.com" as a try at the URL, and end up at Hasbro's Transformers toy page. (PS: I found this link by googling, but it's got no actual data, just opinions.) Tarcil (talk) 17:14, 28 August 2012 (UTC)[reply]

I will say that using a search engine is more likely to get you what you want. Anyone could have registered transformers.com. ¦ Reisio (talk) 17:46, 28 August 2012 (UTC)[reply]
I would say the opposite; I know the exact URLs of almost all the websites that I care to read, and I usually navigate directly to them, rather than searching for them. Anyone could rank highly in a web-search for a keyword - purely at the discretion of the search-engine operator - and the result can change minute by minute; but DNS has a little bit more persistence and requires a formal registration. Certain domains, like .gov, .mil, and .edu, require "sufficient" paperwork to establish identity, while a web-search result simply satisfies the output-criteria of a proprietary, unpublished search-engine algorithm.
It will be almost impossible to collect data "in the wild," because unless you install spyware on a system, or snoop its network traffic, you can't know which URLs it visits. Commercially-sponsored, well-controlled studies have probably been performed to collect such data, but it's unlikely that data is available for free. You might find Mozilla Pancake useful as a start. Here are their user experience data - which looks pretty sparse. And, here's a paper called Effective Browsing and Serendipitous Discovery with an Experience-Infused Browser (PDF) from Stanford's Human-Computer Interaction group. (And, I discovered all of these links without using a search-engine of any kind - by directly typing in the URL of a reliable source, and browsing). Nimur (talk) 18:30, 28 August 2012 (UTC)[reply]
And you'd be wrong. Even if you already know the URI, people make typos. I prefer typing them out myself as well, but using a search engine is going to be more reliable for most people most of the time. ¦ Reisio (talk) 17:47, 29 August 2012 (UTC)[reply]
I'm wrong about many things, but I'm curious: which thing am I wrong about in this case? It's not clear, from your comment. Nimur (talk) 16:43, 30 August 2012 (UTC)[reply]
Considering the OP's link is from four years ago and there haven't been too many major changes to how we use browsers, I think there are still people typing URLs. Certainly, that is what I do if I am pretty sure about the URL - typing "www.<companyname>.<tld>" usually gets me the site I want and if not, then I have to search. My reasoning is that there are so many other sites out there offering opinion, comments, or just a page of links to similar sites that I am not interested in, or worse still offering me a US site of the same company. So for example, if I'm looking for the French language site of a famous swedish furniture store, ikea.fr gets me straight there, while googling offers me ikea.com and links to their US, UK, Canada, Australia and Singapore sites. Anyway, you asked for some data: How about this forum in which the third post says "... read some stats recently that 70% of Internet users type URLs into search bars..." then adds "...the lack of an address bar in Chrome is meant to steer more people back to Google for searches." Unfortunately he doesn't provide a source. Or there's this page about people typing URLs. A search reveals more discussion on this topic, but a quick skim through found no proper data; just discussions. Astronaut (talk) 19:20, 28 August 2012 (UTC)[reply]
One illustration of Nimur's thought of ranking highly in a web search, might go some way to explaining Tango's question here. Perhaps Wikipedia simply ranks higher then Indian universities. Astronaut (talk) 19:26, 28 August 2012 (UTC)[reply]

Google Image Search slows computer down on Fedora 17

Further problems with Fedora 17: When I go on Google to make a Google Image Search that returns very many image hits, and I click on several images to go to the websites they appear on, sooner or later my whole computer starts slowing down. Even moving the mouse becomes difficult. Linux System Monitor shows that the current CPU usage is well over 50%, sometimes near 100%, even though Firefox is the only program doing anything, and even it's only loading a new website or going back to the previous one. Especially going back to the search results list can take over five minutes, during which even moving the mouse is difficult. Once a page has loaded, browsing it is fairly easy, but still prone to minor slowness. Once I close the browser window, everything becomes normal again. This did not happen with Fedora 14. What could there be in Google Image Search that causes such slowness? JIP | Talk 19:13, 28 August 2012 (UTC)[reply]

Have you checked the memory usage? A high level of paging can make things slow down like this.--Phil Holmes (talk) 08:50, 29 August 2012 (UTC)[reply]
A runaway JS script, maybe?Уга-уга12 (talk) 13:34, 29 August 2012 (UTC)[reply]

A better window list applet for Cinnamon?

Still more problems with Fedora 17. After upgrading, I immediately noticed that neither the GNOME Shell or the old GNOME Panel in GNOME 3 were anywhere near to my liking. I agree with Linus Torvalds's criticism that the GNOME project seems to be actively trying to take control away from the user. So I installed Cinnamon, which seems to sort-of work like the old GNOME Panel did. But for my image editing purposes, I would need a window list applet that does the following:

  • If there are few enough windows for all of them to fit comfortably with their names in the taskbar, list them individually.
  • Otherwise, if one application has opened too many windows, group that application's windows into a single list item, clicking on which produces a vertical list of that application's windows, preferably with a tiny preview picture.

The default window list applet in Cinnamon doesn't do that. Instead, it tries to list every window separately, even when there are hundreds of them, making the individual items unusable. The window list of the GNOME Panel in Fedora 14 used to work the way I want.

And while I'm at it, is there a resources applet available? Such an applet should show tiny real-time graphs of CPU, memory, disk and network usage. (Not how much disk space is in use - how much the disk is being accessed.) Again, the GNOME Panel in Fedora 14 used to do this. JIP | Talk 19:46, 28 August 2012 (UTC)[reply]

August 29

Determining PDF page size programatically

I plan to batch-process a large number of PDF files (annotation using a combination of the ps2pdf utility of ghostscript, and pdftk stamp). It would be helpful if I from my script (or C++ program) could determine the page size (and orientation) of the first page of the PDF file. Any ideas about how that could be done? Thanks, --NorwegianBlue talk 09:59, 29 August 2012 (UTC)[reply]

ImageMagick's identify program will display something like
   foobar.pdf[0] PDF 612x792 612x792+0+0 16-bit Bilevel DirectClass 61KB 0.140u 0:00.160
with a [1] etc, for subsequent pages. -- Finlay McWalterჷTalk 10:38, 29 August 2012 (UTC)[reply]
Where 612x792 appears to be the measurements in points -- Finlay McWalterჷTalk 10:44, 29 August 2012 (UTC)[reply]
Excellent, problem solved! Thanks for the quick reply! --NorwegianBlue talk 11:18, 29 August 2012 (UTC)[reply]
It turned out that ImageMagick's identify relies on ghostscript, which it crashed for every pdf I tried it on, resulting in pagefulls of postscript error messages on my system. (I have the most recent version of both packages). I then remembered the xpdf package, and sure enough, there is a pdfinfo utility that among other things returns the page size in points. Worked beautifully. I haven't tried it on documents containing mixed formats yet, but I could always handle those manually, if they turns out to be problematic. --NorwegianBlue talk 21:09, 29 August 2012 (UTC)[reply]
Resolved

Integration of Intel Fortran 11.1 compiler with the Visual Studio 2008

I am trying to integrate Intel visual fortran compiler 11.1 with visual studio 2008. I have successfully installed both and I think I managed to integrate both to certain extent, because now I am getting visual fortran tab, where I make new project and all. I have a 64-bit system and Intel Xeon processor. When I write a fortran program and build it, it gives me the error, "Intel Visual Fortran Compiler for 'Win32' not installed". Please help me with the issue. I am not a programmer, so having problems understanding the nuances. Thanks - DSachan (talk) 12:38, 29 August 2012 (UTC)[reply]

Never mind, I think I managed it. DSachan (talk) 13:59, 29 August 2012 (UTC)[reply]
Resolved

Idea to transfer entire Fedora 17 Linux system to new 2 terabyte hard disk

I think I've come up with a "least troublesome" way of transferring my entire Fedora 17 Linux system to my new 2 terabyte hard disk:

  1. Remove my old disks and put the new disk in.
  2. Boot up with a Fedora 17 installation DVD and install the most minimum system.
  3. Put my old disks back, along with the new disk.
  4. Boot from either the old disks or the new disk, it doesn't really matter, as long as I end up in a working Linux system.
  5. Transfer all the files from the old disks to the new disk, but keep /etc/fstab intact.
  6. Remove my old disks once again.

If I have a bootable partition on both disks, do I get to somehow choose which disk I'm booting from? Or how will my computer decide it? Is such a thing even possible?

Will I automatically get my old user account when I transfer the entire root partition over to the new disk? Exactly how are user accounts stored in Linux? Is there a way to preserve user IDs on the destination when copying files? (But if I mess up the user IDs on the files, it won't really matter, I can always use chown.) JIP | Talk 17:43, 29 August 2012 (UTC)[reply]

"If I have…"
Your computer will likely first attempt to boot from the first disk it sees, which is determined by the cable connection order and the BIOS (etc.)
"Will I automatically…"
Yes, but you could just as well just transfer it over without doing a fresh install and fix /etc/fstab (as explained already in one of your other items).
"Exactly how…"
If you copy everything, everything will be preserved.
¦ Reisio (talk) 17:53, 29 August 2012 (UTC)[reply]

Further question: If I no longer will have any use for the old disks, I intend to sell them or give them away to my siblings. Despite 99.999999% of Finland's population using only Microsoft Windows and thus being unable (or at least not easily able) to read Linux disks, I would much rather not give their new owner access to all my personal files. Will removing all the files and/or reformatting the partitions be enough? What if I modify the partition table, deleting every partition on the disks? JIP | Talk 19:02, 29 August 2012 (UTC)[reply]

Personally I find old disks handy for keeping an old backup (labelled "my system date ddmmyy", wrapped in an ESD bag, and stuffed in a cupboard somewhere). The aftermarket value of old disks is fairly minimal. If you want to blank a disk properly, dd /dev/zero over its entirety. -- Finlay McWalterჷTalk 19:10, 29 August 2012 (UTC)[reply]

whois

In whois for google I see

Extended content
Server COM.whois-servers.net returned the following for GOOGLE.COM

GOOGLE.COM.ZZZZZZZZZZZZZZZZZZZZZZZZZZZ.LOVE.AND.TOLERANCE.THE-WONDERBOLTS.COM
GOOGLE.COM.ZZZZZZZZZZZZZZZZZZZZZZZZZZ.HAVENDATA.COM
GOOGLE.COM.ZZZZZZZZZZZZZ.GET.ONE.MILLION.DOLLARS.AT.WWW.UNIMUNDI.COM
GOOGLE.COM.ZZZZZ.GET.LAID.AT.WWW.SWINGINGCOMMUNITY.COM
GOOGLE.COM.ZOMBIED.AND.HACKED.BY.WWW.WEB-HACK.COM
GOOGLE.COM.ZNAET.PRODOMEN.COM
GOOGLE.COM.Z.LOVE.AND.TOLERANCE.THE-WONDERBOLTS.COM
GOOGLE.COM.YUCEKIRBAC.COM
GOOGLE.COM.YUCEHOCA.COM
GOOGLE.COM.WORDT.DOOR.VEEL.WHTERS.GEBRUIKT.SERVERTJE.NET
GOOGLE.COM.VN
GOOGLE.COM.VABDAYOFF.COM
GOOGLE.COM.UY
GOOGLE.COM.UA
GOOGLE.COM.TW
GOOGLE.COM.TR
GOOGLE.COM.SUCKS.FIND.CRACKZ.WITH.SEARCH.GULLI.COM
GOOGLE.COM.SPROSIUYANDEKSA.RU
GOOGLE.COM.SPAMMING.IS.UNETHICAL.PLEASE.STOP.THEM.HUAXUEERBAN.COM
GOOGLE.COM.SOUTHBEACHNEEDLEARTISTRY.COM
GOOGLE.COM.SHQIPERIA.COM
GOOGLE.COM.SA
GOOGLE.COM.PEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEENIS.COM
GOOGLE.COM.PE
GOOGLE.COM.MY
GOOGLE.COM.MX
GOOGLE.COM.LOLOLOLOLOL.SHTHEAD.COM
GOOGLE.COM.LASERPIPE.COM
GOOGLE.COM.IS.NOT.HOSTED.BY.ACTIVEDOMAINDNS.NET
GOOGLE.COM.IS.HOSTED.ON.PROFITHOSTING.NET
GOOGLE.COM.IS.APPROVED.BY.NUMEA.COM
GOOGLE.COM.HK
GOOGLE.COM.HICHINA.COM
GOOGLE.COM.HAS.LESS.FREE.PORN.IN.ITS.SEARCH.ENGINE.THAN.SECZY.COM
GOOGLE.COM.ESJUEGOS.NET
GOOGLE.COM.DO
GOOGLE.COM.CO
GOOGLE.COM.CN
GOOGLE.COM.BR
GOOGLE.COM.BITERMANSOLUTIONS.COM
GOOGLE.COM.BEYONDWHOIS.COM
GOOGLE.COM.AU
GOOGLE.COM.AR
GOOGLE.COM.ALL.THE.PEOPLE.WHO.SPAM.THE.WHOIS.ARE.SERIOUSLY.ANNOYING.SOMEPONY.COM
GOOGLE.COM.AFRICANBATS.ORG
GOOGLE.COM.9.THE-WONDERBOLTS.COM
GOOGLE.COM.1.THE-WONDERBOLTS.COM
GOOGLE.COM

To single out one record, look it up with "xxx", where xxx is one of the
of the records displayed above. If the records are the same, look them up
with "=xxx" to receive a full display for each record.

>>> Last update of whois database: Wed, 29 Aug 2012 17:52:34 UTC <<<

What has happened here? Why is this random sometimes offensive spam in googles whois record?

Heh, that is an unusual form of spam. It looks like people have subdomains of their sites that start with google.com, so a whois search for google.com finds them. For some reason I don't understand, whois sites are blocked at my office, so I can't see if there is a simple way to exclude those from the search. It doesn't look like we have an article on whois spam. 209.131.76.183 (talk) 18:35, 29 August 2012 (UTC)[reply]
Actually, the whois response lets you know how to single one out. Just put quotes around the domain name. I'm still not sure what the plan is to drive people to their sites this way... 209.131.76.183 (talk) 18:41, 29 August 2012 (UTC)[reply]
I don't believe the whois record is the target of them. They just have google.com subdomains to appear to be Google, for whatever reason that might be. OsmanRF34 (talk) 11:35, 30 August 2012 (UTC)[reply]
Notice the ZZZ domains at the top - it seems like they were picked so they would sort to the top of the list. They are registered as name servers, which is how they get subdomains into the list in the first place. I don't think there is any reason to have a nameserver with such an unusual domain name, and if there is it is also certainly for something shady. I'm still not sure what use this would be for spam or non-spam purposes. 209.131.76.183 (talk) 13:57, 30 August 2012 (UTC)[reply]

Hard disk storage in the future

I just calculated that at my present rate of taking an average of 90 photographs a day (that figure is skewed by the times I visit events like the World Bodypainting Festival - on a normal working day, I take 20 photographs at the most), 20 terabytes of hard disk storage would be enough for the rest of my life. What my niece (she's now 1 year old) or any possible children I might ever have do with my old photographs won't be my problem any more. So what is the easiest and cheapest way of acquiring 20 terabytes of storage? It doesn't necessarily have to be on a magnetic hard disk, but on a local storage medium nevertheless. It should be taken into account that this won't be a problem until about a decade afterwards. Is there any estimate on how storage technology will develop at that time? JIP | Talk 19:23, 29 August 2012 (UTC)[reply]

3TB hard drives are available quite readily these days, so 8 of those would get you 20GB (factoring in loss of space due to file allocation table). But since hard drive capacities are increasing regularly and the price (usually) stable or going down it makes more sense to acquire storage space as needed. Also unless you are planning to keep the same camera, camera resolutions also increasing so future photographs will use more space so your calculations may be off. In regards to estimates, Moore's law and Kryder's Law are interesting AvrillirvA (talk) 19:47, 29 August 2012 (UTC)[reply]
I agree with this. The rest of your life is a very long time to extrapolate things, and by the time you've filled one 3TB disc there will probably be much larger storage available. If you do want 20TB now, I recommend some redundancy. With 8 discs, you'll probably see at least one failure. I would keep at least two copies of everything, and every 5-10 years it might not be a bad idea to get new discs and transfer the data to prevent losing data to discs dying of old age. You could also get a NAS device - it would let you put an array of discs in it allowing you to have access to the 20TB on your network, and would have built in support for keeping redundant data and warning about disc failures. 209.131.76.183 (talk) 19:53, 29 August 2012 (UTC)[reply]
I would suggest backups rather then just redundancy. In particular, relying on a NAS device or any other similar setup as the sole source of redundancy is fairly risky. For starters there is no geographical redundancy so if your house or wherever the NAS device is stored catches fire and takes the NAS device with it, having 100 copies doesn't help. And a single device also runs the risk of something like a power surge taking out multiple hard disks. Further, even a well made NAS device runs some risk from malware or file system problems losing data no matter how many copies are supposed to exist. The risk can be kept to a minimum if you know what you're doing but in all likelihood if you're asking questions about it on the RD you don't. In other words, similar to a bog standard RAID setup, redundancy even in a NAS device is more important for avoiding downtime then protecting data although it also helps with data between backup. If you can afford multiple, sure go for a NAS or RAID setup and remote backups and whatever else. But if you can only afford one, it makes far more sense to have at least one backup stored in a remote location updated resonably often. Nil Einne (talk) 16:09, 30 August 2012 (UTC)[reply]
Did your calculations take into account that the filesizes of your pictures are all but guaranteed to grow? You don't plan on shooting at 16MP for the rest of your life, do you? The Masked Booby (talk) 01:57, 30 August 2012 (UTC)[reply]

IE8 new version opening PDFs in Acrobat

Running Windows 7, which came with both IE8 (unknown bit number) and IE8 64-bit installed. For reasons that I can't understand, the unknown-bit-number browser recently started to take a long time to open new tabs (nearly a minute sometimes), and because I often run with lots of tabs at the same time (the main reason I refuse to use IE9), this wastes a ton of time, so I've just started to use the 64-bit version. For reasons that I can't understand, when I hold down ctrl and click on a link to a PDF, it insists on opening the PDF in Acrobat instead of opening it in a new tab, which is what would happen if I clicked this way on a link to an HTML page in this browser or on a link to a PDF page in the old browser. Any ideas on how to stop this? I've gone to Tools/Internet Options and played around with the General/Tabs settings, but this still happens even though I've selected the "A new tab in the current window" option at "Open links from other programs in". Browsers are versions 8.0.7601.17514 (unknown bit) and 8.0.7601.17514CO (64-bit edition). I've looked around for webpages that discuss this problem, but I can't find anything. Nyttend (talk) 21:09, 29 August 2012 (UTC)[reply]

The "unknown bit" version will be 32-bit. The reason the behavior is different between the two versions is that 32-bit plugins (such as the Adobe Reader one which renders a pdf in the IE window) only work on the 32-bit version. I do not know if Adobe offer a 64-bit version of their plugin, but if they do installing that would solve your issue. AvrillirvA (talk) 21:29, 29 August 2012 (UTC)[reply]

Operating systems

Hi. How many Source lines of code do the following operating systems consist of:

The first three don't release (all) their source code, so it's hard to answer. As to Ubuntu, what do you mean by "operating system"? Just the kernel, or the standard tools as well, or the desktop environment (which?) as well, or the apps (which?) as well? It's hard to draw the line. Marnanel (talk) 23:11, 29 August 2012 (UTC)[reply]
Any rough estimations would be welcome. About Ubuntu I mean the operating system including all the packages and tools on the standard CD that can be downloaded from the Ubuntu website. --41.178.232.21 (talk) 08:26, 30 August 2012 (UTC)[reply]
The article lists some figures (somehow) for NT through to Windows Server 2003, and for various versions of Debian and for OS X 10.4, so it can't be that hard to answer (if you're not a stickler for the answer being meaningful).  Card Zero  (talk) 10:04, 30 August 2012 (UTC)[reply]
Since you'll accept rough estimates, here's a blog post from a Windows developer [2] which says that Vista is said to have over 50 million lines of code.  Card Zero  (talk) 09:44, 30 August 2012 (UTC)[reply]

August 30

Smart TV software updates

Hi, on a Samsung "Smart TV", one of the software update options is called "By Channel", described as downloading the update "over broadcast signal" (other options being over the Internet and from USB). What kind of "broadcast signal" would that be referring to? I am in the UK if that matters. 86.160.215.12 (talk) 01:31, 30 August 2012 (UTC)[reply]

Freeview (UK) carries TV software updates on one of its channels. I nearly fell off my sofa when my Sony TV first announced that it had received a software update and was intent on installing it. See, for instance, this schedule. --Tagishsimon (talk) 01:37, 30 August 2012 (UTC)[reply]
(OP) Really, I didn't know that... Thanks for the quick reply. 86.177.106.27 (talk) 01:57, 30 August 2012 (UTC)[reply]

Popups

I have a website which should be advert free. Occasionally a pop up screen appears. How do I stop it so it doesnt appear for other people? Kittybrewster ☎ 11:42, 30 August 2012 (UTC)[reply]

I had a poke around your website, but didn't get any popups or popunders. Then again, I have fairly robust popup blockers. It might help us to know where you are having the problem, and what steps can reproduce it. It's always possible that it's not something on your website at all - if it occurs when navigating from an external site, that site could be using an 'exit popup' - that is, a window that only appears when you navigate away from it. - Cucumber Mike (talk) 11:52, 30 August 2012 (UTC)[reply]
Or it could be malware on your own machine causing the popups. --Mr.98 (talk) 12:25, 30 August 2012 (UTC)[reply]

iOS's Safari cannot upload files

Why does the Safari web browser built into iOS cannot upload files? 27.64.9.171 (talk) 13:00, 30 August 2012 (UTC)[reply]

Is a hard disk drive a type of RAM?

Hard disk drive states in second paragraph that "Hard drives are classified as non-volatile, random access, ....." but Random-access memory says "In contrast, other data storage media such as hard disks, CDs, DVDs and magnetic tape read and write data only in a predetermined order....."--Gauravjuvekar (talk) 16:07, 30 August 2012 (UTC)[reply]

I think hard disks and CDs/DVDs are always classified as random access, but they aren't classified as memory. "Memory" only covers RAM and ROM. Of course, ROM is random-access and it is memory, but it isn't RAM. And data CDs are called CD-ROMs but they aren't ROM and aren't memory. Basically the definitions make no sense. I'll try to fix the lede of the RAM article at some point if no one else does. -- BenRG (talk) 16:49, 30 August 2012 (UTC)[reply]
This is another case of "standard terminology" not being so standard. "Random access" is being used in two different ways: in the hard disk drive article, to mean all data is addressable; and in the random-access memory article, to mean all data access takes equal time.
Nearly all file APIs provide some method for byte- or word- addressability - especially if they present the files as though they are mapped to memory. However, internal to the disk controller driver, or the file system implementation, nearly all hard disks addressed by sector; and many file-systems are paged into RAM. The details vary between each product, driver, file system, and operating system. So, every byte is accessible ("random access", according to the first meaning). But, spatial locality dictates that some bytes can be accessed faster than others (not "random access", according to the second meaning). Nimur (talk) 17:02, 30 August 2012 (UTC)[reply]

Google Doesn't Work

No matter what I enter or where I enter it, either in the Google homepage or in the bar at the top of the screen, all I get is a blank page with "done" at the bottom. I've scanned thouroughly for viruses and waited a long time but still noothing. What can be done? If I switch to Bing at the top of the screen it works.

  1. ^ http://btsc.webapps.blackberry.com/btsc/viewdocument.do;jsessionid=127F6F6E352B86C1347BBE8A350072A5?externalId=KB27707&sliceId=1&cmd=displayKC&docType=kc&noCount=true&ViewedDocsListHelper=com.kanisa.apps.common.BaseViewedDocsListHelperImpl
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