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 do I fix the Shellshock security vulnerability in debian testing/jessie?

The test command x='() { :;}; echo vulnerable' bash shows that my Debian 8 (Jessie) installation is vulnerable, even with the latest updates. Research shows that there's a patch for stable and ...
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5answers
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How can I add a regular user to the sudoers file?

How can I add more users to the "sudoers" file?
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3answers
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How can I install objdump on Mac OS X?

I want to get the source code of a small command line tool using objdump on Mac OS X. I've used arm-linux-objdump on Linux and find it a great tool. Is there any way to install objdump on OS X? I've ...
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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 ...
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4answers
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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 ...
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4answers
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bash watch command with colors preserved

From man watch: Non-printing characters are stripped from program output. Use "cat -v" as part of the command pipeline if you want to see them. So how do I use cat -v if I want to see the ...
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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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1answer
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How can I logout an open, remote SSH session?

I sshed into a Linux machine (bash shell) from a public Windows machine (in our lab) and forgot to log out. I'm now back at my seat in another room and I am too lazy to walk back and log out that ...
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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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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?
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5answers
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VirtualBox from an existing partition

I installed VirtualBox on my Ubuntu Hardy Heron installation, and I would like to use it to virtualize Windows for those rare occasions that I actually need to do something there. Unfortunately, I ...
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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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15answers
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How do I check whether I am using KDE or Gnome?

or maybe something else? I am using Redhat OS.
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4answers
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Why is it possible to change the password of an admin user on linux?

A few days ago, a friend of mine, wanted to show me that he can use my linux even if I don't tell him my password. He entered in GRUB, selected the recovery mode option. My first problem is that he ...
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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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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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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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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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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 ...
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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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2answers
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Obtain kernel config from currently running Linux system?

I accidentally deleted my .config for my kernel configuration on Linux, and seem to remember there was a way to retrieve the kernel configuration via the proc filesystem somehow. Is this still ...
24
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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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2answers
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scp between two remote hosts from my local

I have two remote hostes. host1-> 10.3.0.1 host2-> 10.3.0.2 Both are installed with ssh and scp. In my scanario, ssh and scp listen to port 22 in host1 and in host2 it is port 6969. Now, using my ...
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4answers
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How do you redirect wget to standard out?

I have a crontab that wgets a PHP page every five minutes (just to run some the PHP code), and I want to send the output to standard out. I couldn't find it in the wget manual. I'm looking for ...
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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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9answers
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Flow chart software for Linux? [closed]

Been using Visio at work to do flowcharts, and I'm liking how easy it is to do overall, notably creating and linking shapes. I'm trying to find something for Linux that works the same way, or at ...
24
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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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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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2answers
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What's the difference between “su” with and without hyphen?

I'm quite new to Linux terminal and I'm not quite sure what the difference between su with a hyphen and su without a hyphen is, for example: su - username vs. su username. I looked into the ...
24
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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 { ...
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2answers
2k views

Is there a one line command to make chmod interactive?

I am looking for something like: ls | ask_yes_no_for_each_file | chmod +x the_files_approved Or similar syntax. Also could work on other commands that you want individual confirmation for.
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3answers
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What is the Linux command that encapsulates almost all of the other commands?

I remember that for Linux running in embedded systems, due to size limitations, it can't pack as many commands as in ordinary workstations. So there is a do-it-all command that can mimic almost all ...
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3answers
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Sudo su vs su linux

If I enter in the password to su when prompted, it doesnt work while sudo su does. Also, when a command is executed using sudo (command), does sudo automatically execute it by root by default (since ...
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10answers
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how do you view all threads running on Linux? [closed]

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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2answers
986 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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6answers
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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 ...
23
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9answers
5k views

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 ...
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2answers
6k views

Maximize window in tmux

tmux shows screen like this: [root@wpc-fc2 init]# |············ |············ ...
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8answers
12k views

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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2answers
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Linux 'man' command: How do I search for a word/phrase and cycle through?

When looking for a certain word or phrase in the man page of linux command, one can type '/' followed by the word/phrase to search for it. What I'd like to be able to do is to search for the next ...
23
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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 ...
23
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2answers
38k views

How do I increase VirtualBox resolution past 800x600 in Linux? [duplicate]

Possible Duplicate: Ubuntu on VirtualBox can only show resolution of 800x600 - how to change it? No matter what I do I cannot get the resolution past 800x600. If I am using a Windows ...
23
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9answers
43k views

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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6answers
8k views

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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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 ...
23
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2answers
9k views

Linux: Is there something similar to “top” for I/O?

My disk often is utilized, but top (and htop, a custom replacement) show nothing suspicious. Is there a way to sort processes by I/O (more specific: disk) utilization? EDIT Found out using iotop ...
22
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6answers
50k views

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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8answers
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How to install PHPMyAdmin on Linux EC2 instance?

I just finished setting up a default Linux EC2 instance and would like to install PHPMyAdmin. I already have Apache and MySQL installed but cannot seem to install PHPMyAdmin. I tried using sudo ...
22
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9answers
88k views

What is the shell command to display contents of a file?

Like that of .txt or .html
22
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4answers
28k views

Find all files on server with 777 permissions

I'm looking for a Linux command to go through all the directories on my server and find all files with 777 permission. The output would be a list of all those files with full path.