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 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 ...
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3answers
2k views

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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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 ...
23
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2answers
686 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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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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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 ...
23
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2answers
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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 ...
23
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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 ...
23
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4answers
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How to reinstall GRUB2 EFI?

After successfully updating my bios, something went wrong and I ended up with a blinking cursor on the top left corner of a black screen. No errors, no nothing. The bios now only listed a SATA: ...
23
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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 ...
23
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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 ...
23
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2answers
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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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1answer
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Linux unzip command: Option to force overwrite?

I am writing a shell script that unzips a ZIP file into an existing hierarchy of files, potentially overwriting some of the files. The problem is that the unzip command asks for confirmation: replace ...
23
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1answer
3k views

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 ...
23
votes
6answers
68k views

Add permanent SSL certificate exception in Chrome (Linux)

I have a problem with a website that has an SSL certificate which doesn't correspond to the website domain. Chrome gives me a warning for this website (and rightly so), which I have to ignore ...
23
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2answers
1k views

Is it possible to compile a Darwin Distro from source, like you can a build a Linux Distro?

I have read through and undertaken Linux From Scratch (and BLFS) and I was wondering, can I follow this guide to create a Darwin Distro by substituting the xnu kernel? Would the process be vastly ...
22
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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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7answers
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ls -d is not displaying directories. Is there a way to get ls to only display directories instead of files and directories

Is there a way to get ls to only display directories instead of files and directories From the man page. -d, --directory list directory entries instead of contents, and do not ...
22
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4answers
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How do I get the size of a Linux or Mac OS X directory from the command-line?

What command do I use to find the size of all the files (recursively) in a Linux or Mac OS X directory?
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4answers
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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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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 ...
22
votes
7answers
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How to auto detect text file encoding?

There are many plain text files which were encoded in variant charsets. I want to convert them all to UTF-8, but before running iconv, I need to know its original encoding. Most browsers have an ...
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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 ...
22
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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 ...
22
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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?
22
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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 ...
22
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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
41k 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?
22
votes
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 ...
22
votes
6answers
6k 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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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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11answers
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Putty Network Error: Software caused connection abort

I have a strange problem: when I'm using putty ssh connecting to a linux server hosted in vmware on my local Windows-7, I often get the error saying "Network Error: Software caused connection abort" ...
22
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8answers
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How do I select all text from a file with nano?

I open a file in Ubuntu nano editor from the comand line and I want to copy all the contents of the file so I can paste it in an another application outside the shell. So far I can only copy using ...
22
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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?
22
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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 ...
21
votes
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 ...
21
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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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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
votes
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: $ ...
21
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2answers
876 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 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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3answers
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How to wget a file with correct name when redirected?

So after some time of searching on google and superuser (and scanning man pages) I was unable to find an answer to something that (I think) should be simple: If you go here: ...
21
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4answers
23k views

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 ...
21
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6answers
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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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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 ...
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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 ...
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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 ...
21
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3answers
4k views

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 ...