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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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 ...
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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4answers
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How do I patch the shellshock vulnerability on an obsolete Ubuntu system that I can't upgrade?

I have a system that I administer remotely (2 timezones away) that runs Ubuntu 9.04, Jaunty. For various reasons, mainly that I'm really leery about trying to do a distribution upgrade from so far ...
22
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5answers
15k views

Save multiple gnome-terminal layout?

I have multiple gnome-terminal windows open. Is there a way to save the settings (window position, no. of tabs, title etc). across OS reboots ?
22
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1answer
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Ubuntu's /etc/alternatives mechanism

I'm trying to better understand Ubuntu's /etc/alternatives mechanism. The basics are easy: it allow for multiple "providers" to be installed on the same machine, and configures which is the default. ...
22
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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
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5answers
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What does the little squiggly ~ do in Linux?

I have two instances of it being used and I am wondering what each does: service=~ mv ~/Desktop/Service$version.tgz $service What does the little squiggly ~ do? Then, after that that, what would ...
21
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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
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4answers
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How do I exit an SSH connection?

I’m connecting to a server via SSH to send a message to a socket server using a command like: ssh 181.169.1.2 -p 5566 After the connection is established and I write the message and send it I ...
21
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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 ...
21
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2answers
898 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.
21
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8answers
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show keys pressed in linux

in windows there is a program called keyboard jedi that shows what keys are pressed on the keyboard. is there an equivalent for linux?
21
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11answers
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Convert unix line endings to windows

I recently moved back to Windows from Linux. I have some files with CRLFs, some with LFs and some that are mixed. Is there a utility that will help me find all my Unix-touched files and convert them ...
21
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2answers
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What is /usr/bin/[ and how do I use it?

I was looking at coreutils and found this as one of the files included as part of coreutils: /usr/bin/[. What is [ and what does it do? It is an executable. I just don't know what it does or how to ...
21
votes
4answers
27k 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.
21
votes
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 ...
21
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7answers
38k 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.
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5answers
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How Do I Find The Hardware Block Read Size for My Hard Drive?

I'm trying to figure out the optimal size for a large copy from my hard drive using dd. I'm trying to figure out what the best blocksize to use it, which I would assume is the hardware block size for ...
21
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3answers
22k views

How to join/merge many mp3 files?

Searching Google on how to join/merge many mp3 files, it suggests that I should just cat them together. That might "work", but clearly it is not the correct way to do it, as each header and set of ...
21
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14answers
3k views

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 ...
21
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4answers
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How do I convert a DjVu document to PDF in Linux using only command line tools?

I've got some documents in DjVu which I'll like convert to PDF. Is there a way to do this using command line OSS tools?
21
votes
2answers
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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 ...
21
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3answers
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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 ...
21
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3answers
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How can I make the bash backtick operator keep newlines in output?

Is there a way to make bash not eat newlines in the backtick substitution? For example: var=`echo line one && echo line two` echo $var line one line two What I want is var=`echo line one ...
21
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2answers
14k views

Measure script execution time

In bash shell, is there a simple way for me to monitor the time taken to run a script and output the time taken?
21
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3answers
16k views

What's difference between group admin and adm?

There's two similar groups in ubuntu: admin and adm, I found that /var/log/apache2 is in the adm group, and default sudoers includes admin group, what's difference between the two?
21
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7answers
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How can I change the amount and size of Linux ramdisks (/dev/ram0 - /dev/ram15)?

Using Linux, when I boot I automatically have 16 16MB ramdisks, however, I would like to create one really large ramdisk to test some software. I found that I can adjust the size of the ramdisks ...
21
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2answers
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Allow specific user permission to read/write my folder

I have a folder /home/samantha/folder that I want to share with the user tom. He can read/write the folder. How do I do that? chown wouldn't do it because I still want to be able to be the owner of ...
21
votes
7answers
138k views

boot Windows from GRUB rescue

This is my situation: installed Ubuntu without a CD (using unetbootin) dual boot installation (Windows XP+Ubuntu) didn't like the installation and decided to boot into Windows and delete the Linux ...
21
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4answers
3k views

Paint.NET equivalent for Linux?

On Windows, my favorite image editor is Paint.NET. However, on Linux, GIMP is as unfriendly as photoshop despite having less features. (i.e. It takes ages to load, their's far too much stuff). Most ...
21
votes
4answers
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Can Linux mount a normal Time Machine sparse bundle disk image directory?

I am looking to see if Linux can mount and read the files natively stored on a Time Capsule over a network share. Like this question, I am looking for something that replicates at least read-only ...
21
votes
10answers
6k views

Is there a Windows or Linux equivalent of Soulver calculator application? [closed]

I've just been shown a brilliant calculator app called Soulver which is only available on Mac OS X Maths on a Mac as it should be Soulver is a new kind of calculator application which uses a ...
21
votes
2answers
1k views

Use vim to edit ANY text on Linux

I come from the Mac world, where I use http://www.hogbaysoftware.com/products/quickcursor to edit text from anywhere in Vim. Is there anything like that on Linux ? I'm already using "It's All Text" ...
20
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5answers
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What is the meaning of “chmod 666”?

I am using Linux. What is the meaning of chmod 666?
20
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2answers
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Updating Time : ntpdate[3108]: the NTP socket is in use, exiting

The time on my system is incorrect for some reason. i need to run an update but i can't seem to be able to this is the errror. ntpdate pool.ntp.org 31 Aug 12:31:59 ntpdate[3108]: the NTP socket is in ...
20
votes
9answers
15k views

What's the difference between the commands “su -s” and “sudo -s”?

What is the difference between the two super user commands, su -s and sudo -s? They both give a shell with access to the superuser account.
20
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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 ...
20
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5answers
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How can I do a HTTP PUT with Wget?

I am trying to use Wget to access a RESTful interface, but I can not figure out how to do HTTP PUT with Wget. How can I do it? Or isn't it prossible?
20
votes
2answers
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Linux Mint doesn't boot after creating a swap partition

When I was creating my Linux hard drive, I skipped creating a swap partition, thinking that 4GB would be enough RAM. Now, I think I do need a swap partition. I asked some people on IRC how to do this, ...
20
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7answers
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zero fill vs random fill

Many tutorials suggest that i should fill a disk with /dev/urandom instead of /dev/zero if i want it to be unrecoverable. But I don't quite get it, how can a disk still be recoverable after being ...
20
votes
7answers
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Can I boot Linux from a VHD?

Is there some way to boot a Linux system from a VHD in Windows 7? If there is a way, how do I put it there in the first place? EDIT: To clarify, I'm not trying to run Linux in a VM. I'm trying to ...
20
votes
10answers
53k views

Differences between Ubuntu Linux and CentOS?

I'd like to know what are the difference between Ubuntu and CentOS. I'm new to the Linux world. Please help me understand which one is good for me to start out.
20
votes
8answers
89k views

How to get an inactive RAID device working again?

After booting, my RAID1 device (/dev/md_d0 *) sometimes goes in some funny state and I cannot mount it. * Originally I created /dev/md0 but it has somehow changed itself into /dev/md_d0. # mount ...
20
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5answers
53k views

How can I edit the $PATH on linux?

I am using ubuntu 9.04 I need to add some folder to my $PATH. I know how to read the path: echo $PATH I want to be able to edit it and add 2 other paths. Thanks
20
votes
2answers
22k views

Linux equivalent to robocopy?

It's kind of funny, there are a lot of ways in which Linux command line tools are vastly superior to Windows ones, but one thing I have not found an equivalent to is robocopy. Robocopy is way more ...
20
votes
3answers
18k views

Why is the CPU usage reported by top in Linux over 100%?

I've seen the CPU usage go over 100%. How is this possible? Is it because I have four CPU cores, so 100% isn't really the max? Also, when a program does this, what else can I do in top besides using ...
20
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1answer
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How can I add Linux to the new Windows 8 boot manager?

Which OSes can be put into the new bootloader that Windows 8 provides? It seems to be quite pretty and consistent with the rest of the new Windows 8 design, so it would be cool to put Linux (Ubuntu) ...
20
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4answers
55k views

What Filesystem to use for Linux Ubuntu? [closed]

I am new to Linux, coming from Windows background. What Filesystem should I use? I read that Ext3 is default still? Ext4 is unstable at times? true? Also is there any performance different between ...
20
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6answers
69k views

Modify fstab entry so all users can Read and Write to an EXT4 Volume

I have an Ubuntu 10.04 box with an EXT4 partition. This partition is set to automatically mount in /etc/fstab. For the purposes of this post, we'll call it: /media/foo. Unfortunately, only root ...
20
votes
4answers
13k 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" ...