A family of Unix-like 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 restart Linux (Ubuntu) from the command-line?

Because of my problem with mouse-clicks being ignored in Ubuntu, I want to restart from the command-line. (I have an open Terminal, and the keyboard is not ignored.) How do I restart a computer ...
47
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4answers
23k views

How to: Unlimited Bash/shell history?

Is there a way to define an unlimited history in Bash ?
47
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1answer
10k views

If I buy a computer with Windows 8 and Secure Boot, will I still be able to install Linux?

I've heard a lot about how Microsoft is implementing UEFI Secure Boot in Windows 8. Apparently it prevents "unauthorized" bootloaders from running on the computer, to prevent malware. There's a ...
47
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1answer
33k views

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: "/var/log/...
46
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9answers
71k views

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.
46
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5answers
10k views

What is the equivalent of Linux's “~” (tilde) in Windows?

In Linux, we can go to the user home by entering the tilde (~) character after cd: cd ~ How to do the same in Windows? Each time, I need to type: cd C:\Document and Settings\freewind That's too ...
46
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3answers
8k views

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 ...
46
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9answers
90k views

How to get parent PID of a given process in GNU/Linux from command line?

Resolved before asked: cat /proc/1111/status | grep PPid
46
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6answers
29k views

Better Ubuntu Fonts

I have been using Ubuntu for a while. I like it. I like it a lot. But once in a while, when I switch to Windows, I feel better because I really like the font. It feels really much pleasant to watch ...
46
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3answers
7k views

How urgent is a *** System restart required *** for security?

To learn a bit of server administration I've set up a simple Ubuntu 14.04 server on which I run a personal website. I've set it to automatically install security updates, but leave out the other ...
45
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3answers
21k views

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 ...
45
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7answers
78k views

How to list folders using bash commands?

Is there any way to list just the folders in a directory using bash commands? ( as the ls command lists all the files and folders )
45
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3answers
52k views

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 ...
45
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5answers
66k views

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 ...
45
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7answers
90k views

Remove file without asking

How can I remove file without asking user if he agrees to delete file? I am writing shell script and use rm function, but it asks "remove regular file?" and I really don't need this. Thank you.
45
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6answers
26k views

Getting macro keys from a Razer BlackWidow to work on Linux

I picked up a Razer BlackWidow Ultimate that has additional keys meant for macros that are set using a tool that's installed on Windows. I'm assuming that these aren't some fancypants joojoo keys and ...
45
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7answers
17k views

Linux equivalent of Windows Registry

What is the Linux equivalent of Windows Registry? If there is no equivalent or similar structure in Linux, how are the things that are done by the Windows Registry handled in Linux?
45
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4answers
26k views

Is there a way to find out what application using most of bandwidth in Linux?

I'm looking for an utility that could show me how much of a bandwidth each process are using. It should just print the data and exit as I want to feed that list into conky.
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2answers
74k views

Where does Google Chrome for Linux store user specific data?

Where does Google Chrome for Linux store user specific data such as bookmarks ? I can't find a .chrome or .google directory under my home directory, any other directory I should look at ?
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7answers
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What happens if mv is interrupted?

What happens if the Linux mv command is interrupted? Say, I'm moving a whole directory to some other place and interrupt it while it's moving. Will the source directory still be untouched?
45
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6answers
146k views

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 ...
44
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3answers
67k views

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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9answers
5k views

Why is Bash everywhere (in most if not all Linux distributions)?

Bash is used by default in every Linux distribution I have tried, over alternatives like Z shell (zsh). Is there a technical or historical reason for this?
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9answers
3k views

How to quickly change the first word in a Bash command?

I would like to improve my workflow a bit with Bash, and I realize I often want to execute the same command to a different executable. Some examples: Git (where I would like to quickly change the ...
43
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7answers
68k views

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 ...
43
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5answers
17k views

tmux disregarding the configuration file

I just installed tmux on Ubuntu 10.04 and tried to remap the prefix key to C-a by creating the file ~/.tmux.conf with these lines: set-option -g prefix C-a unbind-key C-b When starting tmux, both ...
43
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4answers
101k views

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 rpc-...
43
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6answers
28k views

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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5answers
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mount dev, proc, sys in a chroot environment?

I'm trying to create a Linux image with custom picked packages.What I'm trying to do is to hand craft the packages I'm going to use on an XO laptop, because compiling packages takes really long time ...
43
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3answers
85k views

How do I create a 1GB random file in Linux?

I am using the bash shell and would like to pipe the out of the command openssl rand -base64 1000 to the command dd such as dd if={output of openssl} of="sample.txt bs=1G count=1. I think I can use ...
43
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5answers
27k views

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.
42
votes
2answers
7k views

what is the difference between “command && command” and “command ; command”

I see these two usage on Ubuntu "command && command" and "command ; command", e.g. apt-get update && apt-get upgrade What would differ if I use apt-get update; apt-get upgrade? I ...
42
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4answers
42k views

How to wget a file with correct name when redirected?

So after some time of searching on Google and Super User (and scanning man pages) I was unable to find an answer to something that (I think) should be simple: If you go here: http://www.vim.org/...
42
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1answer
120k views

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 ...
42
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4answers
28k views

How to make cut/copy/paste in GVim on Ubuntu work with Ctrl+X,Ctrl+C,Ctrl+V?

By default, the cut/copy/paste short-cuts in GVim on Ubuntu are: Cut "+x Copy "+y Paste "+gP I would like to use control key combos in GVim, like I use in Firefox and othe gnome ...
42
votes
9answers
32k views

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 ...
42
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5answers
25k views

How do I configure SSH so it dosen't try all the identity files automatically?

I have been putting my ssh identity files inside my ~/.ssh/ folder. I have probably about 30 files in there. When I connect to servers, i will specify the identity file to use, with something like ...
41
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8answers
258k views

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 root@...
41
votes
9answers
75k views

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 ...
41
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9answers
151k views

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

Like that of .txt or .html
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3answers
8k views

How to rate-limit a pipe under linux?

Is there a filter which I could use to rate-limit a pipe on linux? If this exists, let call it rate-limit, I want to be able to type in a terminal something like cat /dev/urandom | rate-limit 3 -k | ...
41
votes
3answers
31k views

Ubuntu shutdown fail “* Killing all remaining processes…”

I have a fresh installation of Ubuntu Server. "reboot" works, but shutdown fails on the * Killing all remaining processes... step. I am using: sudo shutdown now After the failure, indicated by [...
41
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2answers
17k views

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 ...
41
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2answers
57k views

Can I create an SSH user which can access only certain directory?

I have a Virtual Private Server which I can connect to using SSH with my root account, being able to execute any linux command and access all the disk area, obviously. I would like to create another ...
41
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4answers
13k views

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?
40
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3answers
18k views

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 ...
40
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5answers
23k views

How can a linux kernel be so small?

An ordinary stable 3* kernel is about 70 mb now. But there are little linux distributions of 30-10 mb with software and other stuff running out of the box. How can the linux kernel be so small in ...
39
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8answers
6k views

Why is -r recursive necessary when copying a directory in Linux?

My question is why is it required to use the -r (recursive) flag when making a copy of a directory? I.e., why do this: $ cp -r dir1 copyDir1 When would I not want this behavior when copying a ...
39
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6answers
39k views

Uploading files to S3 account from linux command prompt

I've got several large files sitting in my linux hosted account that I need to upload to my S3 account. I dont want to download them first and then upload it into S3. Is there any way I can "upload" ...
39
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3answers
13k views

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 ...