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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Give write permissions to multiple users on a folder in Ubuntu

There is a folder that is owned by user tomcat6: drwxr-xr-x 2 tomcat6 tomcat6 69632 2011-05-06 03:43 document I want to allow another user (ruser) write permissions on document folder. The two ...
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4answers
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How do I find (and kill) process running on a certain port? [duplicate]

Possible Duplicate: Finding the process that is using a certain port in Linux I'm using Ubuntu Linux 11.04. How do I write a shell script expression that will find the process running on ...
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5answers
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Why doesn't Gzip compression eliminate duplicate chunks of data?

I just did a little experiment where I created a tar archive with duplicate files to see if it would be compressed, to my awe, it was not! Details follow (results indented for reading pleasure): $ dd ...
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8answers
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How to get parent PID of a given process in GNU/Linux from command line?

Resolved before asked: cat /proc/1111/status | grep PPid
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4answers
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What is effect of CTRL + Z on a unix\Linux application

I was curious and confused that what exactly is the behaviour of CTRl+Z. I know, If a process in running in foreground, and we press ctrl+z, it goes to background. But what exactly happens. Does it ...
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3answers
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Subverting the execute flag on Linux systems. Why is this possible?

Whilst reading this, I found the following exploit: % cp /usr/bin/id ~ % chmod -x ~/id % ls -al ~/id -rw-r--r-- 1 edd edd 22020 2012-08-01 15:06 /home/edd/id % ~/id zsh: permission denied: ...
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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 ...
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3answers
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How to get list of dependencies of non-installed RPM package?

apt-cache show <package> shows also it's dependencies. yum info <package> does not show dependencies, but it obviously know them. How to ask yum for dependencies of specified package?
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3answers
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How to: Unlimited Bash/shell history?

Is there a way to define an unlimited history in Bash ?
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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 ...
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6answers
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How can I diff two XML files?

On Linux, how could I generate a diff between two XML files? Ideally, I would like to be able configure it to some things strict, or loosen some things, like whitespace, or attribute order. I'll ...
22
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1answer
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What is the difference between grep, pgrep, egrep, fgrep?

I'd like a walk through on the differences between grep, pgrep, egrep, and fgrep and how I would use them.
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3answers
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How to have Linux ls command show second in time stamp

Something annoying about ls -l command is it shows only hour and minute for a file(like 08:30). How can I see the second portion(like 08:30:44)? man 1 ls and search for 'second' does not give any ...
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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 ...
22
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9answers
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Any Linux BitTorrent client with support for Magnet links? [closed]

Is there any Linux application (bonus points for being console/headless) that supports Magnet links - like the ones provided now by some famous "bay" for pirate BitTorrent users?
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3answers
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How do I log out of `sudo su`?

I'm using sudo su to start mysql and do some homework with it. When I finish with mysql (or any other command), then I'm still in sudo. How do I "log out", so my prompt changes back from # to $?
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6answers
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Pomodoro timer for linux [closed]

Is there good Pomodoro desktop timer for Linux without a lot of dependencies. I know about pomodairo, but it's made with Adobe Air, which I don't want on my Linux (even if it exists for Linux).
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3answers
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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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4answers
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Can I hibernate Linux without a swap partition?

I hadn't set up a swap partition on my PC, because a) I have plenty of RAM (8 GB) and b) I have large harddrives that I didn't want to chop into tiny pieces, so my smallest partitions are 50 GiB, and ...
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6answers
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Learning the basics of Linux/Unix [closed]

I would like to learn the basics of Linux; In contrast to tutorials that teach how to do common tasks with Ubuntu or something. I'm looking for a structured introduction, not a reference. Also I would ...
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4answers
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Is there a linux command like mv but with regex?

For example I want to mv (.*?).sql $1.php, is there a command that lets me specify renaming patterns?
22
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1answer
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Show only current directory name (not full path) on bash prompt

The way my bash prompt is currently configured, it shows the whole path to the current directory. This is annoying when I'm deep inside a directory tree, as the prompt becomes so long that every ...
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4answers
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How do I patch the shellshock vulnerability on an obsolete Ubuntu system that I can't upgrade?

I have a system that I administer remotely (2 timezones away) that runs Ubuntu 9.04, Jaunty. For various reasons, mainly that I'm really leery about trying to do a distribution upgrade from so far ...
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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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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 ...
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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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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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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 ...
21
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2answers
893 views

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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4answers
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How to type special characters in Linux?

In windows there is possibility to type from keyboard special signs by holding alt key and typing a few numbers, that depends on with sign you want to use. Does it work with linux in the same way?
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4answers
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How do I do a binary diff on two identically sized files under Linux?

I have two identically sized files, and I need to do a binary diff to check whether they're the same. I'm currently runnnig diff file1.img file2.img but it's taking quite a while to process my ...
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4answers
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How to gzip multiple files into one gz file?

I have 100 files: cvd1.txt cvd2.txt ... cvd100.txt How to gzip 100 files into one .gz file so that after I gunzip it, I should have cvd1.txt, cvd2.txt ... cvd100.txt separately? Thanks for your ...
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9answers
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how do you view all threads running on Linux?

I've used 'top', but I need a tool that can give me an arbitrary-time history of threads that have executed on my system (CentOS 5.4)?
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Looping Through Subdirectories and Running a Command in Each

I have a set of repositories sorted into directories based on their VCS (Git, Mercurial, SVN). With Subversion I was able to run svn update * in the parent directory and it would loop through each ...
21
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14answers
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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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3answers
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How do I get out my embedded Windows 8 key from a Linux environment?

I have seen other SuperUser questions on this topic: How to find Windows 8 product key? | How to find Windows 8 OEM product key? However, all of the answers assume you have Windows 8 running. I've ...
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3answers
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Replace OS X's shell commands with the linux versions?

The commands available by default in the Terminal in OS X, don't seem to behave like their linux versions. How can I replace all of them with the actual GNU linux commands? For example sed -i ...
21
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2answers
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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?
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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?
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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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5answers
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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 ?
21
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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 ...
21
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2answers
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What do ALSA devices like “hw:0,0” mean? How do I figure out which to use?

I've searched over and over and can't find any explanation of what "hw:0,0" means. How do I determine the number of my USB audio card? MPD requires me to enter something like this: audio_output { ...
21
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1answer
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Mac OSX - Why is /dev/rdisk 20 times faster than /dev/disk

According to the rasbery pi documentation, You can load your OS to a flash card with either /dev/disk or /dev/rdisk. rdisk stands for raw disk. /dev/disk is a block level device, why would rdisk ...
21
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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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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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4answers
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Delete matching files in all subdirectories

How can I remove all .swp files in all of my subdirectories under Linux?
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7answers
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Can I boot Linux from a VHD?

Is there some way to boot a Linux system from a VHD in Windows 7? If there is a way, how do I put it there in the first place? EDIT: To clarify, I'm not trying to run Linux in a VM. I'm trying to ...
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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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gitk looks ugly / doesn't honor theme settings

I'm running Xubuntu, (actually linux mint with xfce on top, but I suppose it's essentially the same thing) I set my appearance theme to (a modified version of) MurrinaStormCloud, but if I run gitk, ...