Wikipedia:Reference desk/Archives/Computing/2015 February 9

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February 9 edit

best version Linux for a beginner, installing programs edit

I've been thinking of migrating from Windows to Linux for years, and have played around a bit w Ubuntu and Fedora, but still find it rather inaccessible. I have no Unix background, and often can't figure out how to install a program. (Or to get the OS to recognize it once it is installed.) Any advice for a version of Linux that's intuitive to someone who isn't a programmer and doesn't know Linux? — kwami (talk) 03:15, 9 February 2015 (UTC)[reply]

Ubuntu is already amongst the easiest to use, unfortunately. The only one that might be more friendly is Linux Mint. You don't really need to know programming to use Linux, it just opens a lot of doors. However, is there a reason why you can't just learn a flavor? --Wirbelwind(ヴィルヴェルヴィント) 03:28, 9 February 2015 (UTC)[reply]
Well, when I'm using an "easy" flavour, and install a program, and the OS doesn't recognize it as a program, and a friend of mine who's used Unix and Linux for decades can't figure out what the problem is, then it would seem there's a rather steep learning curve. I'd like it if I could install programs without line commands, as in Windows. (There are plenty of reasons to not like Windows, but at least installation's straightforward.) Thanks for the suggestion of Mint, though. I'm thinking of making my laptop dual-boot to wean myself off Windows. — kwami (talk) 03:57, 9 February 2015 (UTC)[reply]
Unetbootin is your tool. You can make a dual-boot from that, relatively pain-free, but make sure you have a partition set up to install on, otherwise it'll be bye bye Windows and files forever. Unetbootin will allow you to download and install any flavour on your partition. You can even run it from a pen drive, without installation, and any files you make can be saved on the hard-drive or pen drive - it's your choice. I use it all the time. KägeTorä - () (Chin Wag) 14:40, 9 February 2015 (UTC)[reply]
The main difference between installing programs on Linux vs Windows is that Linux uses a package manager rather than a standalone installer for each program. Our article has a table explaining the differences. You shouldn't have to use any command line tools to install a program - the popular distros should all include a GUI tool for their package manager, like Ubuntu Software Center. You can use that to browse and install most common programs that are available through the OS's software repository. There's also Steam for games (install Steam through Software Center, then install games through Steam).
For programs downloaded from websites, if they're Linux-friendly, they'll usually include a .deb (Ubuntu and variants) or .rpm (Fedora) download option and when you run that file it should open in the GUI for the package manager to install it. [1] goes over how to install Google Chrome this way.
This article covers all the ways to install software on Linux roughly in order from most to least common for most people. Pretty much the only time you should ever have to use a command line to install a program is if you're compiling it from the source code, which you should rarely have to do.
Most common distros are all based on 2 or 3 "base" distros all based on the Linux kernel, so "under the hood", they're pretty similar. The main differences will be in the user interface/desktop environment. Personally, I found Ubuntu's Unity to be somewhat frustrating (and glacially slow on my old laptop), so I switched to Xubuntu, which is just Ubuntu with the Xfce desktop. We have an article on Comparison of X Window System desktop environments, which is a good starting point. Since it's the same OS underneath, it's possible to switch desktop environments without reinstalling everything, but it can be somewhat complicated. So I would suggest picking an environment you like, then finding a distro that uses it. Mr.Z-man 14:56, 9 February 2015 (UTC)[reply]
Thanks for all the tips and links. They make it seem less daunting. Mint or Xubuntu look promising.
Yes, the desktop is a separate issue. I think maybe I'd like to try something rather different from Windows, so I can see what the advantages are.
  • You could try reading Linux is Not Windows to be able to look at things with a new unclouded mind. Then load Mint onto a pen-drive [2] and have a little play around -without having to compromise you exiting windows installation. Enjoy. If windows was released for the first time to-day it would not stand a chance compared to Mint et al. Linux distros have evolved and is now easier to use maintain than window -but trying is believing. Linux Mint also has a forum where they love to advice to newbies .[3]--Aspro (talk) 20:00, 9 February 2015 (UTC)[reply]
  • If you look around the Mint website you'll see mentions of something called Mint LMDE that make it sound rather scary. It isn't so at all, or I haven't found it so. It's Mint based on Debian rather than Ubuntu and for installation, deinstallation and upgrading of programs uses Synaptic, which is very easy. (Whether it's standard Mint or LMDE, the default color scheme is hideous IMHO; but changing it takes mere seconds, so no matter.) Actually I'm now typing this not via LMDE but via Crunchbang Linux (also based on Debian), whose website makes it sound even more scary than LMDE; it isn't, and the people on its message forums are unusually helpful even by Linux standards. I use LMDE on my newest computer as this computer has more oomph and also because the regular installation of LMDE comes with drivers I needed for wireless, drivers that didn't/don't come with Crunchbang (and I was too lazy to read up on how to get and install them). If you have an older computer, or are feeling a little brave, you might try Crunchbang. -- Hoary (talk) 09:50, 10 February 2015 (UTC)[reply]
The best answers have probably already been given, but another idea is to use something that has a good, understand and forgiving community that can help you through any problems. The Raspberry Pi is designed to introduce children and beginners to programming and Linux, and has a community very welcoming of noobs. You can either get yourself a Pi board (~$35 plus tax) and play around to your heart's content without fear of breaking anything, or you can use Debian Wheezy on your current machine. The Pi's operating system Raspbian is functionally identical to Debian, so any advice from Pi forums such as http://www.raspberrypi.org/forums/ will be applicable. - Cucumber Mike (talk) 10:09, 10 February 2015 (UTC)[reply]
Thanks again. It's going to take me a while to digest all that.
So, one of the main differences between Ubuntu Mint and Debian Mint is the ease of installing programs? I like the idea of not having to reinstall the system to update. Sounds like a pain in the ass, but on the other hand, I'd think reinstalling would eventually result in a cleaner OS than constantly patching an old installed version. Am I right? (Windows at least suffers from so much bloat from updates that eventually it becomes unusable.) But the Debian base is supposed to have a steeper learning curve. Not sure how much more difficult it would be. — kwami (talk) 06:09, 11 February 2015 (UTC)[reply]
Put the fear of a steep learning curve into context. If you had started out on Linux first, you would find converting over to Microsoft to be a much stepper learning curve – by a magnitude of extra effort. So relax. Take it easy and persevere like you did when finding your way around windows for the first time. As I said: Linux is not Windows. Look at it as a good investment of your time to learn a proper Operating System that enables you to do what you want with your computer, rather than what windows allows you to do. One doesn't have to keep reinstalling Mint to keep it running smooth – it is a completely different operating system architecture from windows. If you want to update Mint after a few years -it is a breeze unlike windows. Defrag's are not required on Linux Mint either – it is a totally different type of operating system. You have start somewhere so I am instructing you... nay I am commanding you, to try Mint first on a pen-drive and join the help desks and persevere without getting frustrated -that at first -it all seem very unfamiliar. Yet in the same time it took you to become familiar with windows you will find yourself asking: why did I ever bother with that operating system that came pre-installed on my computer - as Linux is not windows! --Aspro (talk) 18:53, 11 February 2015 (UTC)[reply]
I understand it's not Windows and isn't trying to be. That's part of the attraction. (Though I'm finding I like aspects of Windows 8, such as the touchpad gestures, though a simple tap only works sporadically.) As long as I don't need to permanently remember dozens of Unix line commands, like DOS in PCs before Windows, then I should be fine. I've had times where I've gotten stuck in Linux and no-one seemed able to help (most recently when using Fedora), but hopefully Mint will make things easier. The only question now, then, is Mint-Ubuntu or Mint-Debian? — kwami (talk) 21:08, 12 February 2015 (UTC)[reply]
Being able to use the Linux command line is useful if your doing very, very serious computing – which is usually not 99.9% of PC computer users need. Ubuntu grow out of Debian (Debbie and her husband Ian) and Mint grew out of Ubuntu as a more stable and less hassle 'flavor' or version. Therefore, reading between the lines, I think that you will find Mint, will eventually provide you with the user experience that you hunger for. Then, if you also want to get into the 0.01% you have one foot already there, because your mind will not be stuck in the “there is no alternative to Microsoft – and anyway Linux is too difficult for the likes of you!” sort of FUD. Command you again – just try Mint.--Aspro (talk) 22:35, 12 February 2015 (UTC)[reply]
I'm sorry, I wasn't being very clear. I do want to try Mint. My question is, which Mint? The original/standard Ubuntu-based Mint, or the new-but-maybe-still-rough-around-the-edges revamped Debian-based Mint? I have yet to find a good description of their relative advantages. — kwami (talk) 00:44, 13 February 2015 (UTC)[reply]
Its OK. Wires just got crossed. As a beginner you will not notice any pros & cons between the two. The Ububtu derived are -at the moment- is easier to use and you should find the KDE desktop more familiar perhaps. You can always changes desktops later anyway. Qiana is supported up to April 2019 and is pretty well shorted out by now. List_of_Linux_Mint_releases Try that one.--Aspro (talk) 18:29, 13 February 2015 (UTC)[reply]
Thanks again! Will do. — kwami (talk) 22:57, 13 February 2015 (UTC)[reply]

Citation software edit

Are there any citation software, such as endnote or refworks, which will automatically create a citation if you enter a DOI? 194.66.246.99 (talk) 10:47, 9 February 2015 (UTC)[reply]

User:Citation bot is software than can do exactly this: convert a DOI into a full, standard-form citation. Its source code used to be available on the Wikimedia ToolsLab server, but the page is down. Perhaps if you contact the developers, they can help you set up a version that does not require a MediaWiki server. Nimur (talk) 15:42, 9 February 2015 (UTC)[reply]
Crossref.org [4] will take a DOI into a form, then if you click "actions" you can export as BibTex, RIS, and raw text in many citation formats (IEEE, Harvard, APA). This is fine for any small project, but might not be suited to large batch processing. SemanticMantis (talk) 17:37, 9 February 2015 (UTC)[reply]

Disk Space on Macbook Pro edit

Inspired by a question above, I am using a brand new Macbook Pro (with Yosemite installed). For some reason I do not have any disk space left to download Apps, and I am wondering why. I have an account on iCloud, but that seems to make no difference. How can I find out what is taking up all this valuable space? For such an expensive laptop, it ought to be usable, at least. KägeTorä - () (Chin Wag) 11:05, 9 February 2015 (UTC)[reply]

On the face of it, that seems very implausible, unless you've transferred a lot of media. I think the smallest MacBook now comes with 256GB SSD, and that should leave you plenty for apps - I have all kinds of crap (including a large music collection, a complete UNIX tool layer, and several movies and TV shows), and need less that the 256 GB. Can you select "Macintosh HD" and hit Command-I to get capacity and available space? I usually use the commandline and du (Unix) to find out where space goes (the -h option is useful!). --Stephan Schulz (talk) 11:21, 9 February 2015 (UTC)[reply]
You could also go to the Apple menu and select "About this Mac" and click on the Storage tab. Dismas|(talk) 11:53, 9 February 2015 (UTC)[reply]
One lives and learns! Thanks! --Stephan Schulz (talk) 11:56, 9 February 2015 (UTC)[reply]
Thanks. Capacity is 120.11 GB, and Available is 6.2 GB. Used is 113.91 GB. I have Parallels installed, along with Windows 10 on this virtual hard drive. Could that be the problem? KägeTorä - () (Chin Wag) 11:32, 9 February 2015 (UTC) [Post bizarrely reverted by User:David Biddulph, who does not even appear to be in this conversation.] KägeTorä - () (Chin Wag) 14:48, 9 February 2015 (UTC)[reply]
Apparently OS-X Yosemite fits into 8GB for a basic install, or 16 for a generous one [5]. You seem to have a 128GB SSD (sorry, I did not know that still existed). So some 80-100GB seem to go somewhere else. I don't know how Parallels handles things, but many virtualisation solutions simulate a fixed-size disk, and reserve the full memory. Are you sure about Windows 10? It's only available as a preview, as far as I know - 8.1 is the released version. Windows alone will take up 13 GB for the 64-bit version, so that is a generous chunk. ---Stephan Schulz (talk) 15:04, 9 February 2015 (UTC)[reply]
Yep, a huge "virtual disk" is probably allocated for Windows and OSX sees it as "full" even though it probably isn't. Win 8.1 can apparently take up ~27 gigs by itself, though there are some ways to trim it down [6]. Here are some instruction to reclaim space from the windows virtual disk in Parallels [7]. SemanticMantis (talk) 17:29, 9 February 2015 (UTC)[reply]
I use the terminal command, du -h -d 3 / to produce a human-readable summary of my disk use, three folders deep, starting at the filesystem root. (This may require a long time and/or administrator permission). Another common place to look is ~ (your home directory). Massive amounts of content can accumulate in ~/Application Support, ~/Library/Logs, ~/Library/Developer/ ... and other folders in your home directory. If you find something large and don't know if it's safe to remove (or even what it is), just let us know.
The official out of disk space support is a helpful reference. It also suggests the culprit might be your email... I've seen mailbox caches that can be hundreds of gigabytes.
Nimur (talk) 15:52, 9 February 2015 (UTC)[reply]

Help recovering a crashed hard disk (stuck at ntldr is missing) edit

Hello. I'm hoping someone here can help me in recovering my crashed hard disk. Here's what happened:

  1. My laptop fell from my office table
  2. It would boot but shut down automatically within a minute
  3. Went to a repair shop, had to get the graphics card replaced (apparently it wasn't working after heating up)
  4. After this, the windows wouldn't boot
  5. The repair shop didn't gaurantee recovery of data or windows (original)
  6. Since I no longer have the windows product key (it was only on the back of the laptop and got erased) and never got a Windows Installation disk with the laptop in the first place, I got a new hard disk installed and got the old one a SATA to USB converter case to fix the thing myself
  7. Tried simply plugging in the hdd as an external hard disk, only one partition showed up, and it wouldn't eject, so had to unplug it
  8. Subsequent attempts at accessing it as an external hard disk got me the message that the drives needed to be formatted before they could be used
  9. Then I tried windows Repair command line bootrec.exe with /fixmbr, which worked fine
  10. Then I tried bootsect.exe /nt60 all /force and got the error Could not open the volume root directory. The parameter is incorrect.
  11. Then I tried bootrec.exe with /rebuildbcd to get Total identified windows installations: 0
  12. Then I tried GetDataBack free version which told me after showing me the contents of a partition that it wouldn't recover the partition unless I bought a license
  13. Then I tried testdisk which showed all partitions except one (which might have been the partition I tried to recover using GetDataBack) and showed that the dellutility partition formatted as Fat16 and of 203miB size was bootable while the actual c drive (232giB) was only primary. Since it wasn't showing one partition, I didn't write the partition table using it.
  14. Trying to boot from the hard disk showed a Missing Operating System message.
  15. Today I tried diskpart and marked the actual c drive as active. Diskpart was showing a fake 242giB extended partition entry though. Disk management was showing some partitions, but I didn't look at it closely.
  16. Then when I tried to boot from the disk, it showed the message Ntldr is missing. Press Ctrl + Alt + Del to restart.
  17. Disk management now shows the entire hard disk as unallocated. Diskpart can no longer find any partitions.

Here are my questions:

  1. Is the partition table actually gone or is it just that windows can't recognise it?
  2. Does "ntldr is missing" mean windows (in some form, whether fine or damaged) is present?
  3. Is it possible to repair windows without a repair disk (I can make a usb flash drive but the optical disk reader is broken)
  4. If I create a bootable flash drive with windows on it and set the boot priority to usb mass storage, will it try to boot from the external hdd or the flash drive? Or go straight from the external hdd to the internal hdd?
  5. If I do make a windows usb flash drive and boot from it, will it be able to repair windows on an external hard disk or will it just look at the internal one?

I hope that the windows is present and just needs to be repaired, and that repairing it will be possible without having to physically open up my laptop and reinsert it as the internal hdd.

Also, the laptop is the only computer I have right now, so I have to note down/print any methods I need to try before actually trying them.

It would be a huge help if someone can help me out in fixing this.

Best Regards --117.234.152.207 (talk) 14:59, 9 February 2015 (UTC)[reply]

I think your HDD is physically damaged. It is impossible to say whether the data can be recovered. You should find a specialized firm (repair shop) that can attempt such a recovery. Ruslik_Zero 20:18, 9 February 2015 (UTC)[reply]
@Ruslik0:: First off, thanks for responding.
I doubt if there's been any significant physical damage because GetDataBack free version showed me the contents of a 100giB partition, and TestDisk while reading the disk only got an error at one sector.
And I did go to several specialized repair shop, but the price the guys are asking is more than the cost of a new hdd. To top that, they're guaranteeing that windows will be lost, the entire hdd will be formatted, and then whatever data retrieval is possible will be done. This obviously doesn't inspire much confidence and is why I'm trying the fixing myself.
Also, since asking this question, I've tried accessing the drive using WinHex (free version). It shows my C drive correctly marked as a bootable partition. Sector 63 looks ok. However, sector 64 is missing the bootloader, and WinHex was unable to detect the other partitions (I didn't try the option to recover the partitions).
At this point, I'm thinking about creating a disk image of the entire disk (on a larger external hdd) so as to minimize data loss, then mount the disk image virtually and try to extract the data.
Could you (or anyone else reading this) recommend a FOSS software for creating a disk image for later data retrieval?
Also, answers to the perplexing questions 4 and 5 above would be highly appreciated.
Best Regards--117.225.80.204 (talk) 13:35, 10 February 2015 (UTC)[reply]
Without physical damage it is difficult to explain while ntldr is missing and other strange behavior. Ruslik_Zero 20:22, 10 February 2015 (UTC)[reply]

Using Ubuntu? edit

More googling leads me to believe that I'd be better off creating an ubuntu liveUSB, booting from it, and then using ddrescue to clone the disk, and then gparted (or parted) to mount the image and recover data.
The exact steps are a little fuzzy now but here's where I'm at:
  1. boot from liveUSB
  2. Use #lsblk -o name,label,size,fstype,model to find the failing and destination disks for image creation
  3. Open a new folder in the destination disk, go to the menu File and the Terminal option
  4. Use #ddrescue -d \dev\sda /destination_disk/destination_folder/image_name.img /dest_disk/dest_folder/log_file_name.logfile (Assuming \dev\sda is the failing disk)
  5. Use #parted image_name.img, then unit, then B, then print to find the parition offsets.
  6. Use #mount -o loop,ro,offset=offset_value image_name.img mountpoint to mount the partition image.
  7. Use the file manager (or whatever the ubuntu equivalent is called) to copy the needed files.
I'm confused as of now whether the commands will begin with a # or sudo. I'd highly appreciate it if anyone points out any obvious errors in the above steps.
Again, Best Regards--117.238.182.154 (talk) 15:32, 10 February 2015 (UTC)[reply]
I'm currently have ddrescue running at home, doing the same thing. Quick piece of advice before you get started: Know what your hard drives will be labeled before beginning. Unfortunately, all three of mine (bad drive, drive for image, drive for restore) had the same label. sudo lshw -C disk -short and cat /proc/partitions will only tell you what order they're in and how many blocks are in each, so I had to do some trial and error. Be sure your image and restore drives are empty, as the files within will be wiped out. The steps I am taking are:
  1. Boot from burnt copy of Ubuntu Rescue Remix
  2. Type "live" to load files
  3. sudo mkfs.ext3 /dev/sdb (sdb being the drive for image)
  4. sudo mkdir mnt
sudo mount /dev/sdb mnt
cd mnt
sudo mkdir recovery
cd recovery
5. sudo ddrescue -r 3 /dev/sda image log (sda being the bad drive)
6. sudo umount /dev/sdb and turn the computer off and back on.
7. sudo mkdir mnt
sudo mount /dev/sdb mnt
cd mnt
cd recovery
8. sudo ddrescue image /dev/sdc (sdc being the drive for restore)
9. Using sdc as a slave, attempt to access it with another filesystem. If not, make it active using OS disk utilities.
-- 143.85.169.18 (talk) 18:04, 10 February 2015 (UTC)[reply]
I was actually thinking just about creating a disk image, not copying the failing disk to another hdd. Will creating an .img file (and not copying to a new disk) still delete all the data on the destination disk?
Best Regards--117.238.222.106 (talk) 17:17, 11 February 2015 (UTC)[reply]
I had a laptop that would shutdown after a few minutes, when I could get it to start at all. It would even shut down when running off a boot CD. But when it did run, it could read the HD just fine, so it wasn't the disk itself that had failed. When I shook the HD, I could hear something rattling around inside. Maybe a spring broke or detached? Would probably need to be disassembled in a clean room to repair and copy the data. (Not worth it in my case.) — kwami (talk) 00:06, 14 February 2015 (UTC)[reply]

Do not turn off or unplug your computer edit

Whenever I'm installing a Windows update, I see the usual message of "Do not turn off or unplug your computer". Makes sense: it's updating basic system files, and turning off the computer could cause chaos. But why is unplugging it a problem? I'm using a laptop with a fully charged battery that runs for several hours. Why would there be a problem if I decided to run the update on battery power? Or is this just meant to cover people who would otherwise unplug their desktop or who have laptops with insufficient battery power? Nyttend (talk) 19:01, 9 February 2015 (UTC)[reply]

It screws up the update installation when it hibernates. My mum did that with her computer after I did factory reset and so I had to do a system restore to fix it as it kept restarting and wouldn't properly bit the OS. Sir William Matthew Flinders Petrie | Say Shalom! 20 Shevat 5775 19:04, 9 February 2015 (UTC)[reply]
Some installs can take hours. Even if you prevent the laptop from sleep/hibernate, you don't want to leave a laptop unplugged and unattended whilst mucking with the OS. Also consider that while the installer can probably technically somehow check to see if the computer is a laptop, it's easiest to just have the same instructions for installing on any box. SemanticMantis (talk) 19:44, 9 February 2015 (UTC)[reply]
Yes the same message shows on computers without battery power. Note however Windows nowadays is intentionally robust (as with most OSes). While you shouldn't kill the power during updates, in reality what will most likely happen is it will rollback updates when you turn the power back on and everything will likely work fine. This doesn't of course precluse things going wrong occasionally. Nil Einne (talk) 21:05, 9 February 2015 (UTC)[reply]
I had a laptop that was a few years old that I used as a media center connected to my television, the battery would charge to 100% and last precisely about 90 seconds if I ever unplugged the power. Vespine (talk) 21:46, 9 February 2015 (UTC)[reply]
Either this, or it's all a conspiracy by Big Computa to let them download your hard drive contents, hack your webcam, and run up your Big Electra bill. μηδείς (talk) 22:02, 9 February 2015 (UTC)[reply]
I've hibernated laptops on several occasions during a Windows update, and it has continued quite happily on resume. The problem occurs if power fails before hibernation, or if the computer is only sleeping (with data in RAM) and the power fails, but Windows usually just does a rollback in these circumstances (as Nil Einne explains above). The laptop I am using at present is like Vespine's and it would be foolish to try to run an update on a weak battery, but usually there is no problem with a good battery, especially if your system is set to perform a controlled hibernation when the battery reaches 10% power. (Disclaimer: I offer no guarantee, just an observation based on experience. ) Dbfirs 22:43, 9 February 2015 (UTC)[reply]