Sunday, February 28, 2010

Control Your Children's Internet Access with Gnome Nanny in Ubuntu / Debian

Gnome Nanny is a parental control system. By using Gnome Nanny you can easily  control what your kids are doing in the computer. You can limit how much time a day each one of them is browsing the web, chatting or doing email. You can also decide at which times of the day they can do this things. Gnome Nanny filters what web pages are seen by each user, so you can block all undesirable webs and have your kids enjoy the internet with ease of mind, no more worries! You can download a black list of sites from here

for ubuntu users ppa archive available here
$ sudo add-apt-repository ppa:guadalinex-members/ppa
$sudo apt-get update

Or You can install through synaptic package manager

Saturday, February 27, 2010

How to Solve Screen Resolution Problem in Ubuntu / Debian with Command Line Utility xrandr


X Rezise and Rotare (xrandr) is a utility available in your Linux  system for reseting and resizing your screen resolution. It is a command line utility. so if your display disapperaed ?? No problem you can do it from a Terminal (Press Ctrl+Alt+f1).

First You have to find the possible resolutions with  xrandr -q

$ xrandr -q
Screen 0: minimum 320 x 200, current 1024 x 768, maximum 1024 x 1024
VGA connected 1024x768+0+0 (normal left inverted right x axis y axis) 270mm x 200mm
1024x768 60.0*
800x600 85.1 75.0
640x480 85.0 85.0 75.0 59.9
720x400 70.1

Now you can set your resolution with command
$ xrandr -s 1024x768

More Details
$ man xrandr

Thursday, February 25, 2010

How to Control the CPU Usage of a Process in Ubuntu / Debian Linux with cpulimit

 
CPULIMIT is a very good utility, this can be utilized for limiting the cpu usage of a process.  Limits are expressed in percentage, not in cpu time. This  does not act on the nice value or other scheduling priority , but on the real cpu usage. System administrators can effectively use this for avoiding there headace. The % limit from 0-100 for single processor 0-200 for dual processor.

How to install  cpulimit in Ubuntu / Debian

Open a Terminal and Type the following command to install cpulimit:

$ sudo apt-get install cpulimit

Usage

To limit CPU usage of the process called firefox to 40%, enter:

# cpulimit -e firefox -l 40

To limit CPU usage of the process to 40% by using its PID, enter:

# cpulimit -p 1313 -l 40

To find out PID of the process use any of the following:

# ps -u shibu  (list all process for the use shibu)
# ps aux | grep firefox

You can also use absolute path name of the executable, enter:

# cpulimit -P /opt/firefox/firebox -l 40

Where,

    * -p : Process PID.
    * -e : Process name.
    * -l : percentage of CPU allowed from 0 to 100 for singe processor.
    * -P: absolute path name of the executable program file.

Wednesday, February 24, 2010

How to Control A Relay from PIC Microcontroller - Circuit Diagram

Simply you can control a relay through Pic Microcontroller. See a simple circuit for controlling a single relay with pic 16f628. When RB5 port of pic become High the relay will operate. This Circuit works with non-latching ralays(commonly used relays are non-latching)

Tuesday, February 23, 2010

How to Setup Static IP Address in Ubuntu Linux from command line

This is for system Administrators and power Users

How can you Setup a Static IP Address from command Line.
This is applicable for Debian / Ubuntu and Its Clones

First You have to remove Network Manager .

Then edit the file /etc/network/interfaces with admin privilege

$ gksu gedit  /etc/network/interfaces

add the Ip as per  your needs ( example I am Going to setup  IP address 192.168.0.5):

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# This is a list of hotpluggable network interfaces.
# They will be activated automatically by the hotplug subsystem.
mapping hotplug
script grep
map eth0

# The primary network interface
auto eth0
iface eth0 inet static
address 192.168.0.5
netmask 255.255.255.0
network 192.168.0.0
broadcast 192.168.0.255
gateway 192.168.0.1

Sunday, February 21, 2010

How to Change Password and Profile Picture from Gnome - Ubuntu Tricks

You can Change your User Password and Profile easily in Ubuntu.

Select the menu  System--> Preferences --> About Me

Now You will get a screen as Below. At right top corner you can select change password and change your password
You can Change your profile also from this screen. For Changing Profile Picture Click on the picture at left top corner and change with your own photo.

Tuesday, February 16, 2010

How to Protect Linux Users from Repetitive Strain Injury (RSI) with Workrave


Workrave is a Free Software  that assists in the recovery and prevention of Repetitive Strain Injury (RSI). The program frequently alerts you to take micro-pauses, rest breaks and restricts you to your daily limit. It tracks all of your keyboard and mouse activity . It Supports Several Languages. It shows a slide show for exercises. Very useful ans a must for All computer professionals. 

How to Install in ubuntu / Debian Linux
$sudo apt-get install workrave   or use synaptic package Manager

Monday, February 15, 2010

View All Filetype like 3gp / Avi / Jpeg / pdf / ttf in Ubuntu Linux with Gloobus


By using a Nice utility Gloobus  you can view almost all file type. Gloobus is a free application for GNU / Linux . Gloobus-Preview is an extension for the Gnome Desktop  designed to enable a full screen preview of any kind of file.  It allows instant access to a variety of file types without the need of opening their default application.

You can access the preview mode from several ways, right click on the file you want to preview and choose “Preview” or simply hit the Space key on your keyboard.

Gloobus can currently preview over 40 file formats and its family is still growing:

Images: jpeg / png / icns / bmp / svg / gif / psd / xcf
Documents: pdf / cbr / cbz / doc / xls / odf / ods / odp / ppt
Source: c++ / c# / java / javascript / php / xml / log / sh / python
Audio: mp3 / ogg / midi / 3gp / wav
Video: mpg /avi / ogg / 3gp / mkv / flv
Other: folders / ttf / srt / plain-text


How to Install In Ubuntu 9.10

$ sudo add-apt-repository ppa:gloobus-dev/gloobus-preview
$ sudo apt-get update
$ sudo apt-get install gloobus-preview
$ sudo apt-get upgrade (To upgrade to the patched nautilus)

Finally, restart nautilus
$ nautilus -q
$ nautilus &

 

Simple Lightweight Graphical Latex Editor Ubuntu Linux : Gummi


Most of the research workers and Engineering Students need to make their Project Work and thesis work in Latex. Now Latex is not a nightmare, Lot of Graphical Front end softwares are available for Latex. Here You can See a simple Lightweight Lates Editor for Linux Users. It is written in python


You can Download Deb file from Here

Double click on deb file and install with gdebi
or
$sudo dpkg-i gummi_0.4.5-0ubuntu1_all.deb

Sunday, February 14, 2010

How to instal twitter Client Pino in ubuntu


Pino is a Client for Twitter in GNU/Linux. It is a Gnome application

How To install Pino in Ubuntu
First You have to add PPA for Pino

open a terminal
$ sudo apt-add-ppa repository: vala-team/ppa
$ sudo add-apt-repository ppa:troorl/pin

Now

$ sudo apt-get update
$ apt-get install pino

Easy Way to Add PPA Repositories in Ubuntu Linux : apt-add-repository

If you want add a ppa repository , youu need to add some lines in /etc/apt/sources.list and also need to add the GPG key. I think it not easy for beginners. Now See a simple technique to add  ppa with add-apt--repository

example :
open a terminal and add the following line for adding vala-team/ppa

$ sudo add-apt-repository ppa:vala-team/ppa

Wednesday, February 10, 2010

How to install Songbird Music Player in Ubuntu 9.10 Karmic Koala



Songbird is a opensource Media Player and a web browser,  from the developers of wimamp and Yahoo Music Engine. Songbird is a cross platform utility can be used in Windows, Linux, Solaris  and  Mac. Like Winamp, it supports extensions and skins feathers. It supports a variety of file formats and is an excellent option for organizing your music files in your system. It is derived from mozilla supports Searching for extensions and plugins.

Howto Install Songbird for Ubuntu
Download Songbird from here
You will get the tar.gz file Current Version
Songbird_1.4.3-1438_linux-i686.tar.gz
Now move the file to /opt folder
$ sudo mv Songbird_1.4.3-1438_linux-i686.tar.gz /opt
$cd /opt
Now extract the file using
$ tar xzvf Songbird_1.4.3-1438_linux-i686.tar.gz
It automatically  create a Songbird folder and extract the files in to it.
Change file permissions
$sudo chmod -R 755 Songbird or (chown -R shibu:shibu Songbird)
$cd Songbird
$./Songbird 
        or
$ /opt/Songbird/Songbird

Now Your Songbird will Run
You can add /opt/Songbird/Songbird to your Menu.

Tuesday, February 9, 2010

Major Security Alert for Ubuntu Linux users

Ubuntu Security team  announced a major security alert to users of Ubuntu  On February 5th  .The security flaw is found in the kernel of the different versions of Ubuntu. This makes it vulnerable to the system, allowing the escalation of privileges and gain control of the system by an attacker.

 List of affected Ubuntu releases:

Ubuntu 6.06 LTS Ubuntu 6.06 LTS
Ubuntu 8.04 LTS Ubuntu 8.04 LTS
Ubuntu 8.10 Ubuntu 8.10
Ubuntu 9.04 Ubuntu 9.04
Ubuntu 9.10 Ubuntu 9.10

 It is important to resolve it, update your kernel to the latest version available. Something that many have already done but it is worth remembering.  The importance of this fact is not in the bug is.  It is in how fast it is resolved and as the user community has turned to communicate in all media achievable.

 More info : Ubuntu Security Notice USN-894-1

Monday, February 8, 2010

How to Import / Export OR Backup / Restore MySQL Database in Ubuntu Linux with mysqldump

Backup of database is very important  in Database Projects. You can recover your data when  problems occurs. A variety of  backup strategies are used in  MySQL.  You can choose any one of them. This can also use for Installing your Software from One system to Another. This Method is not Distribution Specific, You can Use same command in Fedora, Mandriva, Debian, SUSE etc.. My Heading is for helping Ubuntu users in  Search.

Export / Backup MySQL database:

Utility named mysqldump  can be used to dump a database or a collection of databases for backup or for transferring the data to another MySQL server. The dump file is a text file which contains SQL statements to create the table and/or populate the table.

How to  export / Backup a  Mysql database to a .sql file

# mysqldump -u USERNAME  -p DATABASENAME > FILENAME.sql

USERNAME is the MySQL admin user
DATABASENAME  is the name of the database that need to be exported /Backup
FILENAME.sql is the name of the file where your data will be exported

Now It will ask for password,Enter  MySQL admin password. 

You can dump all databases by doing:

# mysqldump -u root -p --all-databases > all_my_data.sql

Now We can See How to Import/Restore MySQL database:
Below is the simple command through which you can restore / import the already exported MySQL database file (.sql)

# mysql -u USERNAME -p DATABASENAME < FILENAME.sql


You will be prompted for the MySQL administrator password.

Sunday, February 7, 2010

Planetarium Software for Young Children in Ubuntu / Debian Linux : Stellarium


Stellarium is a free open source planetarium Software for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.
Features
  • default catalogue of over 600,000 stars
  • extra catalogues with more than 210 million stars
  • realistic Milky Way 
  • Drawing of the 88 constellations with their names
  • Drawing of more than 40 messiers objects (Orion, M31 etc..)
  • very realistic atmosphere, sunrise and sunset
  • the planets and their satellites
  • a powerful zoom, time control
  • telescope control
  • eclipse simulation 
Available in Windows, Mac and Linux Platform
How to Install Stellarium in Ubuntu / Debian Linux
Open a terminal
$ sudo apt-get install Stellarium 
Or Use Synaptic Package Manager 

    Thursday, February 4, 2010

    How to Manage Multiple SSH Connections in Ubuntu Linux with SSHMenu


    SSHMenu is a GNOME panel applet , that helps  you for managing all of your regular SSH connections within a single mouse click. Each menu option will open an SSH session in a new terminal window.
    Main Feature 
    imagine if every time you connected to a Critical server the terminal window had a red-tinted background, to remind you to tread carefully. Using terminal profiles, SSHMenu allows you to specify colours, fonts, transparency and a variety of other settings for each connection. You can also  set window size and position.

    How to Install SSHMenu in Ubuntu
    Open a Terminal
    $sudo apt-get install sshmenu-gnome

    See More

    Wednesday, February 3, 2010

    Useful Development Environment (Editor) for PHP / CSS / HTML in Ubuntu :GPHPEdit


    A useful development environment for PHP/HTML/CSS in Ubuntu and other Linux Platform.  gPHPEdit is a GNOME2 editor for  editing PHP files and other supporting files, like HTML/CSS. It has support for drop-down function lists, hints showing parameters, and syntax highlighting.

    Howto Install GPHPEdit in Ubuntu
    Open a Terminal

    $sudo apt-get install gphpedit

    or use Synaptic PAckage Manager

    Tuesday, February 2, 2010

    A Brain Teaser Game for Your Kid, Train Your Brain with Gbrainy in Ubuntu Linux


    Gbrainy is a Linux Utility  to train memory, arithmetical and logical capabilities with many sorts of different exercises of different difficulty levels. It is not only for Kids, It should have something for all ages. It can be used for Develop the capabilities of your Kid, Others who  want to keep their mind in form or just try it out for fun, older people can do  some memory exercises, etc.

    It provides the following types of games:
    * Logic Puzzles: games designed to challenge your reasoning and thinking skills.
    * Mental Calculation: games based on arithmetical operations designed to
       prove your mental calculation skills.
    * Memory Trainers: games designerd to challenge your short term memory. 

    How to Install Gbrainy in Ubuntu
    Open a terminal
    $ apt-get install gbrainy
    or Use Synaptic package manager

    Monday, February 1, 2010

    How to Play swf file(Macromedia Flash) on Ubuntu / Debian Linux


    swfdec-gnome is a very good Tool to play SWF files (Macromedia Flash) on GNOME. This package contains programs to integrate Flash functionality into the GNOME desktop. It's main application is swfdec-player, a stand-alone viewer for Flash files. It also contains swfdec-thumbnailer, a program that provides screenshots for files to display in the Nautilus file manager.

    How to Install in Ubuntu
    Open a Terminal
    $ sudo apt-get install swfdec-gnome
    or use Synaptic package manager