Ubuntu is a free open source operating system based on the Debian GNU/Linux distribution. Consider using http://askubuntu.com/ to ask questions about it.

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104
votes
11answers
78k views

How do I detach a process from Terminal, entirely?

I use Tilda (drop-down terminal) on Ubuntu as my "command central" - pretty much the way others might use GNOME Do, Quicksilver or Launchy. However, I'm struggling with how to completely detach a ...
94
votes
6answers
206k views

How to mount a HFS partition in Ubuntu as Read/Write?

I plugged in my external harddrive (which was formatted on my Mac into HFS+ journaled) to my Ubuntu desktop 9.04 64bit. I am not able to get the drive to mount with write capability, how do I do ...
89
votes
4answers
180k views

How do I install the Sun/Oracle Java SDK on Ubuntu?

Since 11.10 Ubuntu does not provide the sun-java-jdk, how do I install it?
81
votes
6answers
29k views

How to tell from what Ubuntu or Debian repository a package comes?

On a Debian-based system, including Ubuntu, how can one tell which repository a package will be downloaded from, without actually beginning the download? aptitude show and apt-cache info will show the ...
80
votes
7answers
83k views

How to check which apache modules are enabled/installed?

which is the most elegant way to check which apache modules are enabled?
79
votes
7answers
7k views

Is it possible to ping an address:port?

I am not into networking, and I have the following question related to the Linux ping command. Can I only ping an address? For example: miner@raspberrypi ~ $ ping onofri.org PING onofri.org ...
68
votes
7answers
26k views

Running upstart jobs as unprivileged users

What's the canonical way to have an upstart job change its userid and run the script as an unprivileged user? Obviously one can use su or sudo, but this seems hacky (and can generate needless log ...
67
votes
7answers
32k views

Find what package a file belongs to in Ubuntu/Debian?

I frequently find myself missing a program, man page, or other file when working on my Ubuntu 8.04 system. Is there any simple way to look up what package contains a given file (whether it is ...
66
votes
5answers
29k views

Aptitude vs. apt-get: Which is the recommended (aka the “right”) tool to use?

Some time ago I read that aptitude is the preferred tool for installation on Debian-based systems. But when you search around on how to administer a Debian-based system, then aptitude is rarely ...
61
votes
11answers
107k views

How to wipe free disk space in Linux?

When a file is deleted, its contents may still be left in the filesystem, unless explicitly overwritten with something else. The wipe command can securely erase files, but does not seem to allow ...
57
votes
5answers
108k views

How can I list all IPs in the connected network, through Terminal preferably?

Using Ubuntu 10.10, I was wondering if there was a command line command that can list all the IPs of devices connected to the network? I would use this for example, to list all the computers ...
57
votes
6answers
109k views

How can I monitor the CPU temperature under linux?

Is there a package available to monitor and display the CPU temp under linux?
57
votes
3answers
21k views

Change Ubuntu 11 scrollbars back to the old style

The question: I've installed Ubuntu 11.04 and the new scrollbars in Nautilus, GEdit, etc. are driving me insane! How do I go back to the old (Ubuntu 10.10 and earlier) scrollbars? The explanation ...
53
votes
6answers
3k views

Is there a point in installing antivirus on Ubuntu?

I have recently started using Ubuntu. I am wondering about the point of installing antivirus programs on Ubuntu. On SuperUser, I found the opinion that it only detects "windows viruses" and removes ...
50
votes
3answers
10k views

What are “Super Cow Powers” and why doesn't my aptitude have them?

sudo aptitude help aptitude 0.4.11.11 Usage: aptitude [-S fname] [-u|-i] aptitude [options] <action> ... Actions (if none is specified, aptitude will enter interactive mode): ... This ...
45
votes
5answers
8k views

Why is my dual-core CPU recognized as a quad-core one?

My processor is an Intel Core i3-380m. As you can see, it's 2 cores and 4 threads. Although, both Ubuntu 11.04 and Windows 7 seem to think it's a quad-core CPU: Why is this? Is it because there ...
44
votes
9answers
35k views

Run VirtualBox in background, without a window

I was wondering if it's possible to run an Ubuntu virtual machine using VirtualBox in background, I mean, without any window open. The idea is to connect via SSH to the Linux host, that would be ...
43
votes
1answer
35k views

How to reload /etc/environment without rebooting?

/etc/environment is officially the correct place for system wide environment variables. But how can I reload the assignments in this file without rebooting or relogging? Interestingly enough google ...
42
votes
10answers
57k views

Automatically mount external drives to /media/LABEL on boot without a user logged in?

This question is similar, but kind of the opposite of what I want. I want external USB drives to be mounted automatically at boot, without anyone logged in, to locations like /media/<label>. I ...
40
votes
6answers
18k 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 ...
39
votes
3answers
49k views

How to install an updated version of PEAR / PHPUnit on Ubuntu?

Most tutorials online show how to install PEAR by doing this: sudo apt-get install php-pear This installs version 1.6.1. It works great because it's super easy! My problem is that I want to install ...
39
votes
4answers
45k views

How to password protect gzip files on the command line?

I want to create some tar.gz (and possibly tar.bz2) files, using the tar command on Ubuntu 10.04. I want to password protect the file. What is the command to do this (I have Googled, but found ...
38
votes
2answers
4k 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 ...
38
votes
4answers
80k views

How do I create an administrator user on Ubuntu?

I want to create a user having sudo powers in Ubuntu. How can I do that?
37
votes
6answers
77k views

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 ...
37
votes
16answers
46k views

How to synchronize the home folder between multiple computers?

I have three computers at home, and would like to have the /home/ folder tree synchronized between the three. Any files/folders (except those hidden) that are modified/added/removed in one of the ...
37
votes
1answer
23k views

How can I launch the GNOME image viewer from the terminal?

It's the default image viewer for Ubuntu, and apparently it's called Eye of Gnome. I would like to be able to launch it from the command line, passing it a file name to open.
35
votes
7answers
3k views

How can a Linux OS be “based on” another Linux OS?

I've been looking through quite a number of Linux distros recently to get an idea of what's around, and one phrase that keeps coming up is that "[this OS] is based on [another OS]". For example: ...
35
votes
9answers
47k views

How do I add a user to multiple groups in Ubuntu?

What's the command line utility and the arguments it requires?
34
votes
2answers
816 views

How do I teach my linux command line manners?

Whenever I complete something in the command line while using Ubuntu and my computer does something of value to me, I enjoy saying thank you, just because it's the polite thing to do. A typical ...
33
votes
4answers
7k views

Linux equivalent command for “open” command on Mac/Windows?

Coming from Mac OS X, you can type: $ open yourfilehere.txt and your file will open just as if you had opened it from Finder. On Windows, one can type: > start yourfilehere.txt and it will ...
33
votes
4answers
49k views

How to clear DNS cache in Ubuntu?

I'm having problems related to DNS solving in my Ubuntu 9.10. Prior complaining to my ISP I would like to refresh my local DNS cache, like in Windows we do ipconfig /flushdns. How can I do that in ...
33
votes
2answers
28k 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 ...
32
votes
5answers
13k 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 ...
31
votes
13answers
44k views

In Google Chrome on Linux, where is the flv if not in /tmp?

I like to keep videos because I like buffering them and then playing them back-to-back in my media player, I want to be able to stop/restart my browser without losing all the buffered video, and ...
31
votes
5answers
20k views

Change default text editor for crontab to vim

I'm using ubuntu 9.10 and the default text editor is nano, which i hate. (doesn't everyone?) Normally it's not a problem as i just vi or gedit everything but crontab -e is opening with nano. I ...
31
votes
5answers
18k views

Is there a way to show notification from bash script in Ubuntu?

Most of the application can show nicely formatted notification on events that appear on top right corner of the screen. I'm about to write a bash script that will do fairy long processing in the ...
31
votes
3answers
10k views

Zsh not hitting ~/.profile

I've just installed zsh on my Ubuntu system. It seems zsh isn't executing ~/.profile on init. To my best understanding, this should be an automatic behavior. What am I missing?
31
votes
4answers
26k views

VirtualBox to use dual monitors

I am am running Kubuntu Hardy Heron, with a dual monitor setup, and have VirtualBox on it running Windows XP in seamless mode. My problem is, I can't get virtualbox to extend to the second monitor. ...
30
votes
4answers
18k 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 ...
30
votes
3answers
20k 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 ...
29
votes
7answers
3k views

Is it possible to “virtualize” an existing PC?

I'm running Ubuntu Desktop 12.04, and I was wondering if it was possible to somehow take my whole filesystem (everything under /) and create an ISO from it. Then, perhaps, use that ISO as the file ...
29
votes
3answers
38k views

How can I change shell in Ubuntu? [duplicate]

I have a Ubuntu Server VPS and I want to use /bin/bash/ as my shell. How can I change my shell? I have root access but I don't work as root. So dash is my default shell now. I have read How do I make ...
28
votes
3answers
71k views

How does one change user's home directory in Ubuntu 9.04?

Does anyone know how I might change my home directory in the shell please?
28
votes
4answers
17k views

Mac OS X “say” command in Ubuntu?

Is there an equivalent to the Mac's terminal command "say" in Ubuntu 9.10?
28
votes
3answers
11k views

Bad font anti-aliasing in Ubuntu

I'm switching from Fedora 8 to Ubuntu 9.04, and I can't seem to get it to get a good font anti-aliasing to work. It seems that Ubuntu's fontconfig tries to keep characters in integral pixel widths. ...
27
votes
4answers
2k views

How to create a file which is named like a command line argument?

I was wondering how to make a file named as a flag, e.g., if I wanted to make a folder named -a, what commands would do the trick? I tried mkdir '-a', mkdir \-a, and neither worked. I'm on Ubuntu.
27
votes
5answers
27k views

what does the asterisk mean after a filename if you do ls -l

I've done an ls -l inside a directory, and my files are displaying like this : james@nevada:~/development/tools/android-sdk-linux_86/tools$ ll total 9512 drwxr-xr-x 3 james james 4096 2010-05-07 ...
27
votes
2answers
20k views

How can I check the version of packages to be installed with apt-get?

After running apt-get upgrade, I get a list of the packages that will be upgraded. I would like to know the version number for one of these packages. (Not the current one but the one that will be ...
27
votes
3answers
14k views

Set background image in xmonad

I have just switched from Fluxbox to giving xmonad a go, and I am definitely liking it. However, the one thing I haven't managed to do is to change my desktop background. I am using Ubuntu 8 (uh, ...