All posts by Chinmoy Kanjilal

Chinmoy Kanjilal is a FOSS enthusiast and evangelist. He is passionate about Android. Security exploits turn him on and he loves to tinker with computer networks. He rants occasionally at Techarraz.com. You can connect with him on Twitter @ckandroid.

Restore ctrl+alt+backspace Usage in Ubuntu 9.10 Karmic Koala

Ubuntu 9.10 Karmic Koala has ctrl+alt+backspace turned off by default. ctrl+alt+backspace is the key combination used to restart the X server. The reasons for this disabling are unclear. One good thing though, is that it is only disabled and not removed.

To re-enable the ctrl+alt+backspace behavior you need to edit two files. This will enable the setting for all distros with a  Xorg Server version 1.6.0 and lower.

Edit the /etc/X11/xorg.conf file as root. Add the section:

Section "ServerFlags"
Option "DontZap" "false"
EndSection

For Karmic Koala, with Xorg 1.6.3, you need to edit a second file. Edit the file /etc/hal/fdi/policy/10-keymap.fdi as root and add the line:

<merge key="input.xkb.options" type="string">terminate:ctrl_alt_bksp</merge>

That will do the trick.

It you are uncomfortable with all these editing, you can simply do it the Lifehacker way.

Go to System > Preferences > Keyboard Settings. Look for the Layouts tab, expand the “Key sequence to kill the X server”, click the check box next to “Control + Alt + Backspace”. See the post at Lifehacker here.

Ubuntu 9.10 New Features

Ubuntu 9.10 was released a few hours back. The release comes with new features. The promising ones are:

Use of GRUB2:

GRUB2 is available in the Karmic Koala final release. It has completely replaced GRUB. The new bootloader has been re-written from scratch.

Use of ext-4 file system:

ext-4 is the default file system for the new version of Ubuntu. Options for using the earlier file systems are also present.

Better installation process:

A better installation is included as against the earlier boring installation. The new installation shows general information while the installation proceeds.

Boot Splash:

The boot screen or the boot splash screen has been completely changed. It looks much classier now.

Software Center:

Instead of the initial add-remove software, we now have a software center to serve all your software needs.

New wallpapers:

A new set of wallpapers has been included for a change.

These are some of the  improvements that are visible during common usage of Ubuntu Linux.

[ Via earth-hacks ]

Tweak Ubuntu 9.10 Karmic Koala

Ubuntu 9.10 Karmic Koala is out. The installation has improved, boot time has improved and overall performance and experience has been revamped.

Karmic-koala
Karmic-koala

The next thing would be to try out some tweaks or install some missing applications and support. You can try these out:

Add more software:

Add more software and packages to your package manager and Software Center by using a modified sources list. This gives us options to install unsupported applications, media codecs and applications from third party vendors, applications like Opera and Vuze. For a guide on installing more software in Karmic Koala, visit this post on adding more software sources.

Themes:

Although the default Ubuntu theme shipped with the Karmic build is excellent, it is a bit dark and does not go with icons of many applications. In such a situation, you can use this theme for a blue look or this theme for a green look. As obvious, these themes have a focus on the color scheme.

Add handy applications:

Next, you can add some handy applications like Launchy,  KeePassX, Ksplice, SubDownloader.

Nautilus Scripts:

Add nautilus scripts to your installation to get a powerful right click context menu. You can also install the NScript nautilus script package. Visit here and here for nautilus scripts.

You can get more tweaks and customizations at this Ultimate Tweak List.

NScripts Nautilus Script Package

I have already covered Nautilus scripts with a post on image editing nautilus scripts. Nscript is another nautilus script package I found at gtk-apps.org. It deals in general file operations like moving files, copying files and so forth.

nscript-nautilus-script
nscript-nautilus-script

NScript is a set of Nautilus scripts from nanolx.org. This set includes scripts for:

  • Apt: performs some operations with apt-get
  • ckhmd5: check md5 checksum
  • copy to: copies files to a selected location
  • mkmd5: create a md5 checksum
  • move to: move files to a selected location
  • openInGedit: open a file in gedit
  • RootOpenInGedit: open with root privilege
  • SetAsWallpaper: set the selected file as a wallpaper
  • WhichPKG: tells the package a file is from

This is only a stripped down list. There are numerous scripts in the package. These scripts need some dependency packages to function properly. They include sed, bash, zenity, shred, md5sum, nautilus, gawk, grep and gksu.

Get the script at this page. Total size of the scripts is 5 KB.

All you need to do is unpack the archive and move the files to  ~/.gnome2/nautilus-scripts/. This will install the scripts. To access the scripts, bring up the right click context menu and perform the desired operations.

How to Create a Chat Server with Netcat

Netcat is a very powerful network utility for Linux. Netcat was developed in 1995 and has many advanced usages. It featured as one of the Top 100 network security tools of 2006 at rank #4.With netcat, we can perform numerous networking tasks like port scanning, managing connections and setting up servers. One very basic usage of netcat is shown here.

Create a chat server/Client:

Netcat can be used to create a chat server and client. With netcat, we can setup a computer as a chat server and another as a chat client which would connect to that server. This enables chatting between two computers on a network.

To create a chat server, enter this into a terminal:

nc l p port_number'

This will set up a tcp server on the host at the port specified as port_number’. This makes netcat listen to the specified port and relays the incoming message on the terminal with stdout. Connect to the chat server using:

nc server_ip' port_number'c

Now, any connection made to the server on the specified port will set up a chat client through the terminal with stdin.

If you are on a Mac, use only the l switch to create a chat server. So, your command should look like:

nc l port_number'

Connecting to the chat server on a Mac is the same as given above.

Generate a Sources.list with the Ubuntu sources List Generator

Ubuntu source generator allows you to generate a custom sources.list file for your Ubuntu software sources. This will give you a customized software source list which includes all the required packages for applications you use frequently. It will also let you install many packages you could not install earlier because you did not find them in the package-manager. This file(sources.list) is used by the package manager for its updates and managing the list of Applications in the Software Center in Ubuntu 9.10.

To generate the sources.list visit the Ubuntu Sources List Generator homepage. This is a PHP application and is very comprehensive.

Ubuntu-Sources-list-generator
Ubuntu-Sources-list-generator

There are options to select the application as well as the source, separately. Sources for third party applications like Skype, Opera and Vuze can also be added. This gives us a complete sources.lst file. On hitting the generate button, the application provides us with the sources.lst file and the GPG keys, which need to be added manually.

Save the text provided as a sources.list file and replace the file at /etc/apt/sources.list with the new file.

Add the GPG keys and then update your packages at synaptics package manager. You should have new packages and applications in your package manager as well as in the Software Center after reloading the package list.

Speed up Ubuntu Linux bootup

Ubuntu has a slow boot time. There are many hogs at work to bring down the boot performance and increase the boot time of Ubuntu. You can check the boot performance by using an application: Bootchart. I had written a post on Bootchart which you can check here.

There are some other options for you to disable applications and services which are not required in general and have a higher load time at bootup.

Two such services are nfs and ntp.

nfs (network file sharing) is a service which lets us mount a disk as a network disk and make it accessible remotely as if it were a local disk. This service is rarely used by regular desktop users and can be disabled, as it checks for network shares during bootup which is a resource heavy process.

NTP(Network Time Protocol) is a service which synchronizes your clock with various servers over the Internet. This service is not required once you have set the time and if you are not running a server yourself.

Disable nfs by editing the file  /etc/rc.config.d/nfsconf, and disable the entry of NFS_SERVER by setting NFS_SERVER=0.

Disable NTP by entering this code into a terminal:

ntp disable

This will disable ntp for the current active interface.

These services, once disabled can speed up the boot time of Ubuntu or any other Linux distro by quite some seconds.

Upgrade to GRUB2

Grub or the Grand Unified Boot Loader is a popular boot loader for Linux. A few months back, Grub was upgraded to Grub2. Grub2 has been reprogrammed from scratch, giving it better modularity.

Grub
Grub

Grub2 has the following goals:

  • Grub2 has added scripting support for use of loops, variables and functions.
  • Targets a better graphical user interface and dynamic loading of modules at run-time which extends the usage of the boot-loader.
  • With Grub2, we have better portability options across various platforms giving it a wider user base.
  • Grub2 has also added support for non-ascii characters.
  • Object oriented framework for devices, drives, files, file systems etc.
  • Enhanced rescue mode.
  • Cross platform installation.

All these features packed into grub2 gives it a fresh new feel.

Grub2 is available by default in the final build of Ubuntu Karmic Koala. For those looking to upgrade to grub2, follow the tutorial here.

This upgrade has some know issues on some systems. For a similar guide with recovery from an error code of error 15, visit this tutorial on grub recovery.

Order your copy of Ubuntu 9.10

Ubuntu 9.10 is out with many improvements over the 9.04 build and a smoother UI. Hopefully, the previous focus on boot time has also been addressed.

Ubuntu9.10-available-download
Ubuntu9.10-available-download

Get your copy of Ubuntu:

Download:

If you have a working internet connection, you can download a copy of Ubuntu 9.10 Karmic Koala from a server nearest to your location. Go to the download page here.

Order free CD:

You can alternatively order a free CD which usually takes a month to arrive although, the request page says it might take 10 weeks to arrive. To request a free copy of Ubuntu 9.10 visit here. This requires you to have a launchpad ID. You can also create a free ID in case you are new to launchpad.

Ubuntu 9.10 has a lot of development behind it and is sure to turn some heads.

Nautilus Scripts for Batch Image Processing Operations

Nautilus scripts are one of the biggest strengths of the Gnome desktop environment and the nautilus file manager. With Nautilus scripts, we can perform complex file manager and file specific operation with a few clicks. One such example is editing of images.
There are many applications available for editing images in Linux but a nautilus script has its own advantages. To know more about Nautilus scripts, visit this post on Nautilus Scripts. These are the five nautilus scripts you can use for fast image editing:

Rotate all images recursively in a directory:

This script rotates all images recursively in a directory. This rotates the images in the directory and any image in the subdirectory as well. The only disadvantage is that it rotates in one direction only.

Script Link

Depends on: jhead

Resize images:

This script is used to resize and compress images in a directory. This is a very handy tool for bloggers and for uploading images to the web.

Script Link

Depends on:  zenity, imagemagick

Rotate-Mirror images:

This script rotates images by 90 °, 180 °, 270 °, vertical mirror and horizontal mirror. Also, this script makes the changes directly on the image being modified and deletes all earlier exif data. It cannot edit files in a directory but can edit multiple file selections.

Script Link

Depends on: zenity, imagemagick

Convert to jpeg:

With this script, we can convert all selected files to .jpeg images. The quality of the image is set to 75; you can set it to a higher value for a better quality. The maximum value is 100.

Script Link

Depends on: convert, sed

SVG to PNG:

This script converts images from svg to png format. This script like the rotate images script cannot convert files in a directory with directory selection but works on multiple files.

Script Link

Depends on: zenity, inkscape

Save the script-text as a file into the nautilus directory and make it executable. These scripts will fail to work without the respective dependencies. The dependencies can be installed from the package manager or from the apt-get command line utility. For details on using the script, see this earlier post on nautilus scripts.

All About Nautilus scripts

Nautilus is the default file manger of the Gnome desktop environment. Nautilus scripts can extend the behavior of the Gnome desktop and act as plugins to the Gnome desktop environment. Here are some of the general questions on Nautilus and Nautilus scripts:

What actually is Nautilus and what are Nautilus Scripts?

Nautilus is the default file manager of Gnome. A nautilus script is basically a shell script which we can place in a special nautilus directory. This gives added functionalities to our file manager.

I am new to Ubuntu. Are Nautilus Scripts for me?

Nautilus scripts are like plugins and addons. If you are new to Ubuntu or to Linux as a whole, you will miss some windows features like send to bluetooth device, open with command prompt etc. In that case, you can use nautilus scripts to make things easier. Nautilus scripts are for anyone and everyone who want to save those extra clicks and key-presses.

What do I do with the script to make it usable?

All you need to do is copy and paste the script into the scripts directory ~.gnome/nautilus-scripts. Then open a terminal, navigate to the script directory and make the script executable using:

chmod u+x "script_filename"
Some nautilus scripts are available as .deb installers. They can be directly installed by running the installer package.

How Do I call the script?

That depends on the script you want to call. If it is file manager specific like “Open terminal here”, you need to right-click on an empty space in the window and select the required script from the context menu. If it is a file operation, right click on the file and select the operation to be performed. When you call a script on a file, what basically happens is that the filename is passed as an argument to the script from the Nautilus file manager.

Will the changes I am making affect my installation?

Nautilus scripts are like plugins. They run independent of the system as a whole and only attach to the running instance of the application being used with and when called. They do not patch into the application.

Nautilus scripts are a great way of exploring the customizations of Ubuntu. Use of nautilus scripts is highly recommended.

Emerald Window Manager: Must Have Ubuntu Software

Window decorations and effects is a powerful feature of the Ubuntu compiz package. But, the themes we generally use are not able to skin the window border and add effects to it in a complete manner.

To get this desired effect, we can use the Emerald Window Manager.

Emerald Window Manager is an application which binds with the compiz desktop to provide us with added effects like shadow and glass pane on the window borders.

emerald-theme
emerald-theme

The Window manager comes with many built in window decorations which we can use. In addition to this, many downloadable window decorations are also available. We can also edit the decorations to adjust the depth, width and height. The glass pane can also be customized to a huge extent. The title bar can be set to roll up or maximize right from the emerald settings. Emerald is a must have application for customizing the look of your windows.
Emerald themes come as .emerald files. To open an emerald theme file, simply double click it. It opens with Emerald. Emerald theme files are really small in size and are applied as soon as we select them in the application.
The theme might not work as desired initially immediately after the installation. In such a situation, enter into a terminal:

emerald --replace

to install Emerald, enter the given code into a terminal:

sudo apt-get install emerald

Techie Buzz Verdict:

This is the only software of it’s kind in Ubuntu. The theme files are extremely small in size and are available readily at www.compiz-themes.org and www.gnome-look.org. Applying themes is very easy and tinkering with the settings can give a variety of effects. The application has some initial problems while loading the window borders for the first time. From next run, it works like a breeze. It works with all Ubuntu based distributions.

Techie Buzz Rating: 4.5/5 ( Excellent)

Ubuntu Based Linux Distributions Worth Trying Out

Ubuntu is no doubt the most popular Linux distribution out there. Although, sometimes you would like to go for something different from the mainstream, you are so much into Ubuntu and are so reluctant to try out another distro. In such a situation, you can try out some other Ubuntu based distributions. That way, you are in for some added support, some modified features and you are still using a lot of Ubuntu.

These are the three Ubuntu distributions I would recommend in such a a situation:

Linux Mint:

mint-linux
mint-linux

Linux Mint is an Ubuntu based distribution with a release cycle in sync with that of Ubuntu. Mint has many browser plugins, media codecs and support for java built in. That gives Mint all the distractions(thats’ what Ubuntu calls it) Ubuntu lacks. Not only this, the Mint desktop is one of a kind and has a very smooth UI. Mint Linux is fully compatible with Ubuntu repositories. With all these features built into an extremely user friendly OS, Mint is my favorite distro second to Ubuntu.

gOS:

gos-linux
gos-linux

gOS is a Linux distribution with a tight integration with many Google services. The Google services are available as desktop widgets. It uses Enlightenment and Gnome as the default desktop.

Ultimate Edition:

ultimate-edition-linux
ultimate-edition-linux

Ubuntu Ultimate edition is a Linux distro with a huge list of Ubuntu applications integrated into it. It supports one click upgrades and has extensive support for many different networking applications like Wifi, Bluetooth etc. It also has many modified visual aspects and a special theme pack.

For more information on Linux Mint visit here.

For more information on gOS visit here.

For more information on Ultimate Edition visit here.

Defrag your Hard-disk with Shake

Shake is a file-system independent defragmentation software. Shake is very effective for defragmenting the ext3 Linux file system as support for offline defragmentation has been removed in the ext3 file system. Shake runs in the userspace and not in the kernel space, probably uses library functions  instead of system calls.

Whether ext3 needs defragmentation or not is itself a hugely debated topic and in my opinion it does not need frequent defragmentation. But, any file system gets mixed and matched after prolonged usage. You can check the level of fragmentation using the fsck command for any mounted disk. Alternatively, you can also use shake to check fragmentation using

shake -pvv my_dir

To install Shake, follow the instructions here.

Shake is currently available as Debian .deb installers and redhat rpms.

Using shake:

Using shake is utterly simple.

shake directory-name defragments any directory.

shake full_path_to_mount_point defragments any mounted disk.

find -iname '*.mp3' | sort | shake defragments all the mp3 files in a drive and place them in lexical order.

You can try out more combinations for a powerful usage. Shake is a really cool application and is the most handy one in its category.

Techie Buzz Verdict:

Shake is a very useful application and is easier to use than most other defragmentation softwares. It also has capabilities for selective defragmentation and has a lot of customizable options.

Techie Buzz Rating: 3/5 ( Good)