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Questions tagged [linux]

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.

Tux

The name "Linux" originates from the Linux kernel, originally written in 1991 by Linus Torvalds. The main supporting system tools and libraries from the GNU Project (announced in 1983 by Richard Stallman) are the basis for the Free Software Foundation's preferred name GNU/Linux.

Linux is used on a broad range of computer hardware, including: microcomputers, mainframes, mobile phones, supercomputers, tablet computers, game consoles, set top boxes, and routers. Linux is packaged as a distribution which typically includes the kernel itself and all the various utilities, libraries and applications intended for that particular distribution. It is of note that in most cases, the underlying source code is both free and open source.

Popular Distributions

Most Linux questions on Super User are about …

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How can I sort the output of 'ls' by last modified date?

How can I sort the output of ls by last modified date?
nearly_lunchtime
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6 answers

How do I make a machine "blank screen" for a period of time (as a penalty) if certain noise levels are reached?

My kids (4 and 5) yell a lot when playing games on the computer. I found an effective cure for this. When I hear loud noises, I ssh into the game computer and do: chvt 3; sleep 15; chvt 7 This will turn off the screen for 15 seconds on Linux.…
Leonid Volnitsky
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View list of files in ZIP archive on Linux

How can I view the list of files in a ZIP archive without decompressing it?
johnlemon
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How to execute a command whenever a file changes?

I want a quick and simple way to execute a command whenever a file changes. I want something very simple, something I will leave running on a terminal and close it whenever I'm finished working with that file. Currently, I'm using this: while read;…
Denilson Sá Maia
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Permissions on private key in .ssh folder?

I changed my permissions in my .ssh folder and now when I use a piece of software that uses my private key, I have to type my password each time. What should my permissions be on my id_rsa file to not have to type a password each time I use an app…
Jody G
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How to find a directory on linux?

I have a VPS with Suse Linux 10.3. I've logged in via SSH/putty and am trying to find where my web files are located. Since I'm uploading via FTP in a directory called httpdocs, I assume that this directory exists somewhere. My google searches have…
Edward Tanguay
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What is the "You have new mail" message in Linux/UNIX?

Sometimes, when I log into a box and 'su' to root, I get a cute little message saying I have mail (thank GOD it's not AOL). Where is this mail? What does it contain? Who/What sent it? How important is it? Is this even actual "mail" in the same…
n0pe
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Automatically answer 'Yes' when using apt-get install

Is there a way to make apt-get install answer "yes" to the "Do you want to continue [y/N]?"?
mistiry
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When reading a file with `less` or `more`, how can I get the content in colors?

When I read a file in Linux with the command less or more, how can I get the content in colors?
Open the way
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How to turn off word-wrap in less

Short version: How can I make the less utility in Linux not wrap lines? Long version: Often I need to view huge CSV files using less with hundreds of columns. I frequently only care about the first couple columns. However, word wrap causes one…
User1
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Reload a Linux user's group assignments without logging out

When assigning a user's secondary group list using: # usermod -G is it possible to force this group assignment to take effect without logging out all running sessions? This would be very useful in the situation where a Screen…
Simon
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Did I just get hacked?

I am developing a consumer product, and it is supposed to be connected to the Internet, so as expected, it is connected to the Internet so that I can properly develop it. I went away for an hour or two, and when I came back to my office I noticed…
vaid
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How to decompress a .bz2 file

I have a file as: filename.bz2 I need to decompress. I have tried the command: tar xvjf filename.tar.bz2, but it didn't work as the file is not a tar file. How do I decompress this file?
Jury A
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Test if a port on a remote system is reachable (without telnet)

In the old days, we used telnet to see if a port on a remote host was open: telnet hostname port would attempt to connect to any port on any host and give you access to the raw TCP stream. These days, the systems I work on do not have telnet…
Steve HHH
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What is the difference between executing a Bash script vs sourcing it?

What is the difference between executing a Bash script like A and sourcing a Bash script like B? A > ./myscript B > source myscript
Scottie T
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