Linux refers to the family of Unix-like computer operating systems using the Linux kernel. If your question is about a certain distribution only, use a more specific tag.

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How to run a minimal Linux inside a running 64-bit Windows 7

On my previous Windows Vista laptop, I used to run Portable Ubuntu Remix for Windows, which is based on coLinux, like the similar andLinux. This worked fairly well with limited system resources (a ...
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7answers
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Which is more efficient - tar or zip compression? What is the difference between tar and zip?

I'm working in Linux environment and want to know about tar and zip commands. Which is more efficient - tar or zip? I also need to know the differences between the tar and zip commands. Can anyone ...
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5answers
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Are Linux commands interchangeable with Unix commands?

I find that some commands, for example, ls and pwd, can be used on both Linux and Unix systems. Is it that all Linux commands can be used in the Unix systems, and all Unix commands can be used in ...
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6answers
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why run a Linux shell command with &?

I am using Red Hat Linux Enterprise version 5. I've noticed people sometimes running commands with a couple of & options. For example, in the below command, there are two & signs. What is the ...
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2answers
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What does Linux do with existing files in a mount point?

If I attempt to mount a folder that already has files in it, does linux give me an error message or go ahead and show both the mounted filesystem and the files that were already in the folder?
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2answers
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How to create a directory named '-p' under Linux with Bash? [duplicate]

In Bash, how could I create a directory named -p? mkdir -p failed. mkdir "-p" failed. mkdir "\-p" failed. mkdir \-p failed.
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7answers
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Copy directory contents using 'cp' command

How do you copy all the contents of one directory into another? For example: $ cd /home/newuser $ cp -a /backup/olduser/* . The problem with the above is that the globing pattern '*' matches the ...
21
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3answers
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Convert a PDF to greyscale on the command line in FLOSS?

I have a colour PDF file, and I'm going to print it out and then photocopy it in black and white. I'd like to know what it's like in B&W before photocopying it. Is it possible to 'greyscale' a PDF ...
21
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7answers
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How can I keep a process alive after closing the putty session?

I am using putty to interact with Linux server. I have started a process using putty. The process is running and will take 5-6 hours. I want that process to keep running after I close the putty ...
21
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2answers
591 views

What problems does udev actually solve?

For that matter, what exactly was wrong with a bunch of static files in /dev? It's apparently unsatisfactory enough for developers to have reinvented this wheel by my count 3 times now (devfs -> udev ...
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5answers
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Sudo vs root; any actual differences?

I'm working with a support member for a product, and he insists that I need to be root to install a series of patches, and that sudo won't work; he doesn't provide a reason but seems very firm in his ...
21
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7answers
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How to set current time on Linux?

Why is the output of the following commands different? root@vmi2115:/var# hwclock Sun 26 Jun 2011 01:21:38 PM CEST -0.273230 seconds root@vmi2495:/var# date Sun Jun 26 15:21:39 CEST 2011 ...
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9answers
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How to track LAN usage? (AKA 'top for LAN')

There's an evil application that is eating ALL my upload bandwidth (I'm brazilian, it's only ~35kbps) for like 80% of the time my PC is turned on. I would like to know if there's any way to track ...
21
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2answers
21k views

How can I create a non-login user?

I'd like to create a user and a group both called subversion on a RHEL 5 system. I looked at the man page for useradd and I guess the command would be just be... useradd subversion However, not ...
21
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3answers
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How do you find the parent process of a zombie process?

How do you find the parent process of zombie processes? When the child process is something where the parent is not entirely obvious... Is there some way to list processes in tree format or ...
21
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14answers
3k views

How to become a Linux superuser? [closed]

What process/reference/book/faq/tutorial/quickstart/primer/etc would you recommend to a lifelong Windows guy who wants to become a Linux superuser? EDIT Perhaps I should provide a little bit of ...
21
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4answers
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How do I get ls --color=auto to work on Mac OS X?

I'm trying to move my bash configuration from Ubuntu to Mac OS X and it looks like ls is slightly different. For instance, it won't accept the --color option. How do I get this to work?
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8answers
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How to extract text with OCR from a PDF on Linux?

How do I extract text from a PDF that wasn't built with an index? It's all text, but I can't search or select anything. I'm running Kubuntu, and Okular doesn't have this feature.
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3answers
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How to show output on terminal and save to a file at the same time?

I am using: user@unknown:~$ sudo command -option > log to save the results of "command" to the file "log", but I'd like to also get the result on the terminal, is this possible? I am using ...
21
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7answers
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Linux keylogger without root or sudo! Is it real?

Somebody on Youtube claims to have a keylogger on Ubuntu that was neither executed nor installed as root. The link below shows a demo of it working. http://www.youtube.com/watch?v=Y1fZAZTwyPQ ...
21
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2answers
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Is it possible to install the Helvetica font on linux?

I don't know too much about the licensing issues surrounding fonts, but I would like to install Helvetica on my machine for my own personal use. I haven't been able to find a whole lot about this on ...
21
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1answer
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logrotate configuration file syntax - multiple wildcard entries possible?

Since the man page doesn't answer my question and I don't want to force a rotation cycle, I decided to ask the question here. The man page for logrotate gives the following example: ...
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4answers
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Can unexpected power loss harm a Linux install?

I am developing an application on a Linux embedded board (runs Debian) e.g. Raspberry Pi, Beagle Board/Bone, or olimex. The boards works on an environment that the electricity is cut unexpectedly (it ...
21
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2answers
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What is /dev/mem?

Presumably it's somehow related to memory? What would sudo cat /dev/urandom > /dev/mem do? Trash all RAM? All non-kernel virtual memory? None of the above?
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4answers
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Paint.NET equivalent for Linux?

On Windows, my favorite image editor is Paint.NET. However, on Linux, GIMP is as unfriendly as photoshop despite having less features. (i.e. It takes ages to load, their's far too much stuff). Most ...
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2answers
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Enable Emacs-like keybindings scheme for all QT applications

As for GTK apps under Gnome environment it's possible to set all applications to use Emacs-like input scheme: $ gconftool --set -t string /desktop/gnome/interface/gtk_key_theme Emacs $ gconftool ...
21
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2answers
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Use vim to edit ANY text on Linux

I come from the Mac world, where I use http://www.hogbaysoftware.com/products/quickcursor to edit text from anywhere in Vim. Is there anything like that on Linux ? I'm already using "It's All Text" ...
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5answers
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What does the little squiggly ~ do in Linux?

I have two instances of it being used and I am wondering what each does: service=~ mv ~/Desktop/Service$version.tgz $service What does the little squiggly ~ do? Then, after that that, what would ...
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6answers
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play mp3 or wav file via Linux command line

I would like to make an alarm system backed by a Ubuntu (no graphical interface) box, which plays various announcement and alarm audio tracks (.mp3 or .wav) via the command line. For example: $ ...
20
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5answers
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Copy entire file system hierarchy from one drive to another

I would like to copy the entire file system hierarchy from one drive to another..i.e contents of each directory as well as regular files in Linux platform. Would be gratefull to know the best way to ...
20
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2answers
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What is /usr/bin/[ and how do I use it?

I was looking at coreutils and found this as one of the files included as part of coreutils: /usr/bin/[. What is [ and what does it do? It is an executable. I just don't know what it does or how to ...
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5answers
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On Linux/Unix, does .tar.gz versus .zip matter?

Cross-platform programs are sometimes distributed as .tar.gz for the Unix version and .zip for the Windows version. This makes sense when the contents of each must be different. If, however, the ...
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2answers
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Slight delay when switching modes in vim using tmux or screen

Switching to and from insert mode in Vim is no longer instantaneous since I use tmux. After pressing Esc in insert mode, it takes a noticeable amount of time to actually get out of insert mode. After ...
20
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3answers
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In Linux, how do I truncate command-line output?

If I grep -nr sumthin * in my source code directory, it also spews out very long lines from minified JavaScript or CSS files. I want to get just the first 80 characters per line. For example, a ...
20
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2answers
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List files bigger than filesize specified

How can I make ls (or any other particular command) to list me only files bigger than a specific file size?
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1answer
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Is there a way to make bash more TAB friendly?

I use bash on both my Mac and as my cygwin shell. Overall, I'm quite pleased with it. My one complaint however is that its TAB completion isn't as good as Windows Command Line TAB completion. For ...
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2answers
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Can GNU Grep output a selected group?

Is it possible to use GNU grep to get a matched group from an expression? Example: echo "foo 'bar'" | grep -oE "'([^']+)'" Which would output "'bar'". But I would like to get just "bar", without ...
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8answers
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How to check the health of a hard drive

My SATA drive started clicking and I was unable to access the data. It was not clicking loudly though, like a drive that has already gone bad. After tightening the connections to the hard drive, it ...
20
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1answer
12k views

Measure script execution time

In bash shell, is there a simple way for me to monitor the time taken to run a script and output the time taken?
20
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3answers
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What's difference between group admin and adm?

There's two similar groups in ubuntu: admin and adm, I found that /var/log/apache2 is in the adm group, and default sudoers includes admin group, what's difference between the two?
20
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2answers
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How do I create a relative symbolic link in Linux?

I need a symlink that resolves relative to the directory it is placed in. What command is used to create such a thing?
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3answers
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Does rm -f follow symbolic links?

I have a directory like this: $ ls -l total 899166 drwxr-xr-x 12 me scicomp 324 Jan 24 13:47 data -rw-r--r-- 1 me scicomp 84188 Jan 24 13:47 lod-thin-1.000000-0.010000-0.030000.rda ...
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7answers
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boot Windows from GRUB rescue

This is my situation: installed Ubuntu without a CD (using unetbootin) dual boot installation (Windows XP+Ubuntu) didn't like the installation and decided to boot into Windows and delete the Linux ...
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5answers
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How can I know the absolute path of a running process?

If I have multiple copies of the same app on the disk, and only one is running, as I can see with ps, how can I know the absolute path to distinguish from the others?
20
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5answers
13k views

Save multiple gnome-terminal layout?

I have multiple gnome-terminal windows open. Is there a way to save the settings (window position, no. of tabs, title etc). across OS reboots ?
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10answers
5k views

Is there a Windows or Linux equivalent of Soulver calculator application? [closed]

I've just been shown a brilliant calculator app called Soulver which is only available on Mac OS X Maths on a Mac as it should be Soulver is a new kind of calculator application which uses a ...
20
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1answer
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Ubuntu's /etc/alternatives mechanism

I'm trying to better understand Ubuntu's /etc/alternatives mechanism. The basics are easy: it allow for multiple "providers" to be installed on the same machine, and configures which is the default. ...
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4answers
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What's the difference between .profile and .bash_profile, and when do you configure which? (Mac) [duplicate]

Possible Duplicate: Difference between .bashrc and .bash_profile What's the difference between .profile and .bash_profile, and when do you configure which? I.e if I configure the ...
19
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14answers
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Linux command to repeat a string n times

Is there any built-in linux command that allows to output a string that is n times an input string??
19
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4answers
1k views

Should I kill zombie process in my system?

Since I'm newbie in Linux/Unix systems and just read about zombie processes, I have one question. I have 10 of them right now. Do I need to kill them and if yes, why? Are they a load on my system? ...