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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30
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3answers
31k views

Disable MySQL startup in Ubuntu 10.04

I want to prevent MySQL from starting in Ubuntu 10.04 I have used update-rc.d -f mysql remove and confirmed that there is no link to the /etc/inid.d/mysql script from any of the rc?.d directories. ...
29
votes
3answers
12k 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 ...
29
votes
7answers
4k 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
4answers
98k views

How to upload one file by FTP from command line?

I need to upload a single file to FTP server from Ubuntu. This operation should be done in a script (in non-interactive mode). What is the right syntax for ftp? I'm trying this, to no avail: $ ftp ...
28
votes
8answers
6k views

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 ...
28
votes
5answers
44k 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 ...
28
votes
8answers
15k views

Clipboard manager for Ubuntu?

I'm looking for a good program for managing clipboard history on the Ubuntu desktop used primaraly for software development. Ditto is exactly what I need, except it wont run on Ubuntu.
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
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 ...
26
votes
2answers
4k views

Why is it so hard to find a file in Ubuntu?

It's very hard to find files in Ubuntu. In Windows, you could just go to C:\Program Files and you would find what you need. In Ubuntu, you must use search to find something you need. Maybe I am ...
26
votes
4answers
38k views

How do I make Bash my default shell on Ubuntu?

I have a .bash_profile in my home directory, but it isn't getting run on login. If I do the following, then things seem to be as I expect: ssh myhost bash source ~/.bash_profile But normally that ...
26
votes
7answers
42k views

tar: Exiting with failure status due to previous errors

I have written a little script that tars and compresses a list of directories + files. The script appears to run succesfully, in that a useable .tar.gz file is created after the script runs. ...
26
votes
7answers
4k views

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 ...
26
votes
8answers
35k views

How to extract text with OCR from a PDF on Linux?

How do I extract text from a PDF that wasn't built with an index? It's all text, but I can't search or select anything. I'm running Kubuntu, and Okular doesn't have this feature.
26
votes
9answers
18k views

Remote desktop to Mac from various platforms (Windows, Ubuntu)

I fear I know the answer to this already, but I would like to be able to connect to my Mac Mini in a 'remote desktop' fashion. I would like to connect to my Mac as if I were sat at my desk, but I ...
26
votes
8answers
12k views

Find all user-installed packages

Is there any way to get a list of all user-installed packages on an Ubuntu system, i.e. the packages that were installed on top of the default installed packages? (The idea is to get a comprehensive ...
25
votes
7answers
37k views

'No such file or directory' error in bash, but the file exists?

On Ubuntu, I get a 'No such file or directory' error when I try to execute a command. I have checked with ls -la , the file adb is there and it has 'x' flag So why I am getting a 'No such file or ...
25
votes
2answers
18k views

How to add a mp3 handler to sox?

I want to play music in the terminal with sox. # install sox/lame sudo apt-get install sox sudo apt-get install lame # play music play music.mp3 # play FAIL formats: no handler for file extension ...
25
votes
3answers
21k views

Are there any real advantages to assigning more “cores” to VirtualBox?

I have an 2.8 quad core i7 with a VirtualBox. I have the option of assigning up to 4 cores to a guest machine, but I have only been doing two. What are the advantages/disadvantages of assigning more ...
25
votes
13answers
33k views

Enable System Beep in Ubuntu

I have tried and tried to get the system beep working, but with no success. I have selected System-->Sound-->System Beep-->Enable Audible Beep (from the Gnome Desktop) I have tried from a Terminal ...
25
votes
4answers
37k views

How do I install Maven 3?

I am using Ubuntu and need to upgrade to Maven 3 from Maven 2. Can someone please help me install Maven 3?
25
votes
6answers
63k views

How do you disable an upstart service in ubuntu 10.10?

In 10.10 upstart is being used instead of sysvinit. It's possible to remove annoying upstart services which you do not want by removing the appropriate file in /etc/init/blah.conf However, this ...
24
votes
4answers
67k views

How to update Google chrome in Ubuntu?

How to update Google chrome in Ubuntu?
23
votes
4answers
74k views

How can I add a regular user to the sudoers file?

How can I add more users to the "sudoers" file?
23
votes
9answers
5k views

How to track LAN usage? (AKA 'top for LAN')

There's an evil application that is eating ALL my upload bandwidth (I'm brazilian, it's only ~35kbps) for like 80% of the time my PC is turned on. I would like to know if there's any way to track ...
23
votes
5answers
21k views

How do I stop services from starting on boot on Ubuntu?

I have lots of servers installed (Apache, MySQL, etc.), but I don't want them all to start at boot time (they drain power, and I'm on batteries most of the time). How do I configure this?
23
votes
5answers
15k views

How can I open a .7z file in Ubuntu?

How can I open a .7z file in Ubuntu?
23
votes
1answer
12k views

sh: make: not found

I got the following error message: sh: make: not found I guess I need to install make, or a compiler on my Ubuntu 9.04 Could you tell me what I exactly need to type to install it ? thanks
23
votes
4answers
1k views

How can virtual machines consume so little RAM on the physical host machine?

I'm running VirtualBox on a Windows XP machine with 2GB RAM. I've created a virtual Ubuntu machine and allocated it a base memory of 750MB. Just to put it to a test, I ran 20 things at once on the ...
22
votes
6answers
42k views

play mp3 or wav file via Linux command line

I would like to make an alarm system backed by a Ubuntu (no graphical interface) box, which plays various announcement and alarm audio tracks (.mp3 or .wav) via the command line. For example: $ ...
22
votes
10answers
24k views

How to upgrade Git on Ubuntu Hardy?

I have Git version 1.5.4.3 installed, but I think this must be an old version. I'm running Ubuntu Hardy 8.04. I need to install at least version 1.6 to get a Git GUI to work. How do I upgrade my ...
22
votes
4answers
27k views

How do I find (and kill) process running on a certain port? [duplicate]

Possible Duplicate: Finding the process that is using a certain port in Linux I'm using Ubuntu Linux 11.04. How do I write a shell script expression that will find the process running on ...
22
votes
7answers
11k views

Linux keylogger without root or sudo! Is it real?

Somebody on Youtube claims to have a keylogger on Ubuntu that was neither executed nor installed as root. The link below shows a demo of it working. http://www.youtube.com/watch?v=Y1fZAZTwyPQ ...
22
votes
4answers
37k views

How do you add a certificate authority (CA) to Ubuntu?

My work has decided to issue their own certificate authority (CA) to handle different aspects of our work securely without paying for certificates. Cryptographically sign emails Encrypt email ...
22
votes
2answers
20k views

Is it possible to install the Helvetica font on linux?

I don't know too much about the licensing issues surrounding fonts, but I would like to install Helvetica on my machine for my own personal use. I haven't been able to find a whole lot about this on ...
22
votes
3answers
51k views

How do I log out of `sudo su`?

I'm using sudo su to start mysql and do some homework with it. When I finish with mysql (or any other command), then I'm still in sudo. How do I "log out", so my prompt changes back from # to $?
22
votes
4answers
14k views

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
votes
3answers
13k views

How to open Mac Keynote presentations on Ubuntu?

How to open Mac Keynote presentations on Ubuntu? Can it be imported to Impress?
21
votes
3answers
42k views

How to run a cron job as a specific user?

I would like to run a cron job as a specific user on my machine. How may I specify the user for a cron job to run as?. I am running on Ubuntu 10.0.4 [Edit] The cron jobs will be running on a ...
21
votes
2answers
44k views

Where can I get the repositories for old Ubuntu versions?

Where can I get the old repositories for Ubuntu versions? In my case, it's 9.04 Jaunty? I found all the official repositories and their mirrors have been removed. I am wondering where I can get the ...
21
votes
6answers
59k views

Why do I need to enter a password for the Default Keyring to unlock?

When I log into Ubuntu, I am prompted every time to: Enter Password for Default Keyring to Unlock I want to avoid this step since I am the only person using this machine and I see no reason to have ...
21
votes
3answers
15k 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
votes
5answers
9k views

What is the difference between Debian and Ubuntu?

From what I heard Ubuntu is a basically a Debian Linux with some extra applications and drivers pre-installed in order to make it more user friendly. Is that all? Or are there deeper, more ...
21
votes
1answer
12k views

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. ...
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
votes
3answers
4k views

How do you run the previous command in emacs shell?

I am in terminal mode on Ubuntu, and I'm running emacs with 2 buffers open, one is a ruby file, and the other is a shell (opened by typing M-x shell ), and when I switch to the shell buffer, I want to ...
20
votes
3answers
6k views

How do you find the Ubuntu version (release number / name) from the command line?

How do you find the Ubuntu version (release number / name) from the command line?
20
votes
5answers
28k views

How can I view results of my cron jobs?

I see so many guides on how to run crontab, but what I need right now is to learn how to Find log files about cron jobs Configure what gets logged
20
votes
4answers
51k 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
votes
5answers
21k views

Synergy Key Mapping

I'm running a Synergy server on Ubuntu and a Synergy+ client on OSX. The server has a standard windows keyboard with shift, ctrl, windows, and alt keys. My MacBookPro has shift, fn, control, ...