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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What does the 'rc' in `.bashrc`, etc. mean?

Well, this is embarrassing. I feel like I just realised I don't know a loyal colleague's name after working with them for 10 years. "Hey, er... *cough!*, thanks for that great job you did on setting ...
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1answer
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How do I unzip a tar gz archive to a specific destination?

I want to unpack a .tar.gz file to a specific directory. The archive file is in /root/Documents. I want to unzip it into /root/Desktop/folder. The folder structure in zipped file should be preserved ...
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mount dev, proc, sys in a chroot environment?

I'm trying to create a Linux image with custom picked packages. I followed the guide here http://www.olpcnews.com/forum/index.php?topic=4766.0 However, when I tried to install some packages, it ...
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3answers
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How to add a command in vim editor?

If suppose my source code file name is "foo.c". While editing and debugging i always execute this command:- :!gcc -g foo.c -o foo;gdb foo Can I add a custom command to Vim such that If i type ...
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5answers
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Does running commands verbosely make them slower?

I've found myself using the -v flag for lots of applications less and less (especially for trivial stuff like tar and cp). However, when I did and I was, say, unzipping a large file, it would take ...
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1answer
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Why does deleting from the command line take significantly less time than from a GUI?

Something I wondered about as I was deleting a dozen or so images from my computer: With a quick rm -rf command on the directory's contents, all the images were gone in a snap. When I drag the same ...
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3answers
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How can I log all process launches in Linux

I would like to get a log of all processes that are launched with the time that they were launched and the arguments they were launched with. Is this possible in Linux?
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7answers
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How to know which Linux Distribution I'm using?

How to know which Linux Distribution I'm using? uname -a gives Linux xxxxxx.net 2.6.9-42.0.3.EL.wh1smp #1 SMP Fri Aug 14 15:48:17 MDT 2009 i686 i686 i386 GNU/Linux How can I know this is ...
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8answers
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Swap partition size on a 64 GB RAM computer for memory-intensive work

I have 64 GB RAM and 240 GB SSD on my computer, which I'm going to use for memory-intensive calculations (machine learning, data mining, etc.). Most of the advice I found on the Internet are ...
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3answers
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How to analyse disk usage in command line linux?

du and df are nice, but I don't know how to filter the data they provide the way I do with SequoiaView. I would like to know which are the largest folders and the largest files in a glance.
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How do you set a password for transmission-daemon, the BitTorrent client server?

The config file is ambiguous, and keeps getting overwritten when you restart the daemon in Debian, anyway. In /etc/transmission-daemon/settings.json, there are these options: rpc-username ...
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9answers
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How to convert Word (doc) to PDF in linux?

I have a set of files in .doc format, that need to be converted to .pdf format. I am using Ubuntu linux.
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3answers
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What's all those users in the /etc/passwd file?

The /etc/passwd is supposed to have a line for every user on the system. Amongst the common username and root there is a bunch of other users. Some examples: timidity:x:114:127:TiMidity++ MIDI ...
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10answers
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How to Remove the Last 2 Lines of a Very Large File

I have a very large file ~400G, and I need to remove the last 2 lines from it. I tried to use sed, but it ran for hours before I gave up. Is there a quick way of doing this, or am I stuck with sed?
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Linux: Compare Directory Structure Without Comparing Files

What is the best and simplest way to compare two directory structures without actually comparing the data in files. This works fine: diff -qr dir1 dir2 But it's really slow because it's comparing ...
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3answers
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If I know the PID number of a process, how can I get its name?

If I have the PID number for a process (on a UNIX machine), how can I find out the name of its associated process? What do I have to do?
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7answers
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Batch-convert files for encoding

How can I batch-convert files in a directory for their encoding (e.g. ANSI->UTF-8) with a command or tool? For single files an editor helps, but how to do the mass files job?
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4answers
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what does the dot mean at the end of -rw-r--r--. How do you set it with chmod?

I see that some of the files in my directories under Linux have a . at the end of the permissions listing. what does the dot mean at the end of -rw-r--r--. How do you set it with chmod ?
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Swap partition size for 4GB RAM

I'm planning to install Ubuntu 9.04 version. How much space should I dedicate for swap partition. I remember setting it to double the RAM size when I installed long back. At that time my RAM was 256 ...
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3answers
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Can a process be frozen temporarily in linux?

I was wondering if there is a way to freeze any process for a certain amount of time? What I mean is that: is it possible for one application (probably running as root) to pause the execution of ...
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Booting Linux off USB pendrives

Booting a Linux system off USB Pendrives is one of my favorite things. On a laptop we have the following advantages, The Harddisk can be shutdown and that reduces power consumption (hdparm) The ...
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2answers
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Linux - Mount device with specific user rights

How can I mount a device with specific user rights on start up? I still have some problems figuring it out. I would like to mount the divide with uid=1000 and gid=1000. My current entry to the ...
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How do I execute multiple commands when using find?

I'm trying to run multiple commands on things I have found, how can I achieve this? find . -exec cmd1; cmd2 does not seem to work; it instead runs cmd2 after cmd1 has been executed on every file.
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8answers
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How can I merge the gnome clipboard and the X selection?

I'm constantly frustrated by the two separate clipboards in X/Gnome. I'm constantly doing things like control-C to copy, and then middle-click to paste, and getting the wrong data. Or select ...
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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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3answers
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Have a file named ~ (tilde) in my home-directory (Linux)

I just noticed that I have a file called ~ in my ~-directory. $ ls -la ~ ... -rw-r----- 1 x1 x1 733962240 Mar 1 17:55 ~ ... Any idea how I can mv or rm it?
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4answers
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How to lock a file against deletion but still make it writeable?

I want to make a file locked against deletion but still be writeable. How do I do this? The file in question is a truecrypt volume as a file on a NAS SMB Network share, so I don't want to ...
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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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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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3answers
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Case Insensitive search from find command?

I am not able to figure out how can I do case-insensitive search using the find command. I tried find . -name -i pattern And it does not work.
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5answers
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How to determine available free space on Ubuntu?

I am in a situation where I am getting an error when I try to save a file to my Ubuntu server via ssh. It says there isn't any available space left. I don't know how that can be true. What should I do ...
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Why create many partitions?

I have noticed that when installing Ubuntu some people create multiple partitions for directories. Like one for root, one for home, one for boot. What is the advantage to doing this over installing ...
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Linux: find out what process is using all the RAM?

Before actually asking, just to be clear: yes, I know about disk cache, and no, it is not my case :) Sorry, for this preamble :) I'm using CentOS 5. Every application in the system is swapping ...
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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 ...
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5answers
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Linux / OS X tar incompatibility – tarballs created on OS X give errors when untarred in Linux

When I tar up files on my Macbook and untar them in Linux, I repeatedly get the following warnings/errors: tar: Ignoring unknown extended header keyword `SCHILY.ino' tar: Ignoring unknown extended ...
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5answers
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How to use different network interfaces for different processes?

I have two network interfaces on a Linux PC, and I need to manually set the interface that a given process will use. The program (Twinkle softphone) does not have a similar option, so I believe that ...
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3answers
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How accurate is `md5sum`?

When using md5sum to verify the integrity of a file, how accurate is the process? Does a verified MD5 mean that EVERY bit is exactly the same, or is there a threshold that must be broken before ...
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8answers
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How can you see the actual hard link by ls?

I run ln /a/A /b/B I would like to see at the folder a where the file A points to by ls.
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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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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 ...
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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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4answers
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How to check which timezone in Linux?

is there anyway to check which time zone i'm currently in Linux?
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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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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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What is the different between 'locate' and 'find' in Linux?

Why there are two so similar command in Linux? and normally what are the circumstances to use each of them?
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1answer
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Permission denied when accessing VirtualBox shared folder when member of the vboxsf group

I'm running Ubuntu 11.04 (guest) on Windows 7 (host) with the guest additions installed. I have an auto-mount folder that maps to my D: drive on the host which I can access using sudo ls ...
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2answers
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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 ...