How to install Samsung SCX-4521-NS multifunction printer in Linux?

Steps to install drivers for SAMSUNG SCX-4521-NS multifunction printer

1. Download the driver file for linux from the following url

http://www.samsung.com/in/support/model/SCX-4521NS/XIP-downloads?downloadName=DR

2. extract the downloaded file then open Applications → Terminal

Assume that the downloaded file is in the directory ~/Downloads

3. Issue the following commands as in the same order

$cd ~/Downloads/uld

$./ install.sh

give proper values (mostly yes/no options) whenever prompted

4. Once the driver got installed, connect your printer with the PC/Laptop then do the following steps

5. Go to Applications → System tools → Administration → Printing this will open printer configuration wizard.  (Am Using a debian derived distro named BOSS GNU/Linux, in your destro the "Printing" may be available under different menu item, with different name)

6. Click on Add button, give password whenever prompted. The connected printer will be automatically detected and then click on Forward button. Now a new popup window will open select the option “provide ppd file”

7. Now browse to the location of ppd file (which is /usr/share​/ppd/uld-samsung)

8. Now select the ppd file with the exact name as “Samsung_SCX-4650_4x21S_Series.ppd”

then proceed.

9. Now, test your configuration with “print test page”

How to add CD/DVD entry into Debian Linux source.list file

In Debian based linux(deb package management system) Linux "/etc/apt/sources.list" is the file which tells your linux box where the repository.  Regardless of the new packages installation mode (whether via terminal with apt-get command or with synaptic package manager) this file is referenced to fetch the needed .deb files.  For this method you need to have a good internet connection.

If you have installation CD/DVD you can add this to the source.list file and use that as your repository(only to install the packages available in the CD/DVD).  how to do that?

[What apt tool actually needs is a catalog file to use (packages.gz) and the original .deb packages.  As the installation CD/DVD contains it we can use the same as like online repo.]

1. Insert your CD/DVD into the drive and ensure it is mounted properly

2. Go to terminal by
Applications -> Accessories -> Terminal (Steps for BOSS GNU/Linux)

3. Type the following command

$sudo apt-cdrom add

This command will add the cdrom entry into the /etc/apt/sources.list.

4. Now update your apt file with the following command

$sudo apt-get update

5. Install the packages you need by

$sudo apt-get install

Gpick - A Color picker for debian based GNU/Linux .

Screenshot of gpicker

 

   After a long time again tried to create web page with HTML5 & CSS3.  As the work progressed as usual endup with doubts/needs/queries.   This time it is about getting the hexadecimal code of a color for using in CSS.  Some of friends told that to know the color code, first take screenshot of a we page or the desktop application & open the same in gimp then using the color picker tool find the color code.  This is one kind of solution (like going around one's head to touch one's nose... :p).

I came across this awesome desktop applicaiton called "Gpick" home page of Gpick (Yes, for GNOME Desktop environment).   Its just cool, I need not even to explain how to use this application, it as simple.  Just install by

$sudo apt-get install gpick

and give a try.

Note: I am using BOSS GNU/Linux a indian version debian linux.

How to remove libreoffice configuration/settings in debian based linux to fix the settings change problems?

Some times we do accidentally change the some settings of the libreoffice and endup with
1. weird/awakward views of our documents
2. problems in exporting our documents from one format to another say .odt to .doc
3. Alignment issues etc.,

So, If you don't know how to revert the settings/configuration you changed, or forget what changes you made.. there is one simple way to revert to the default settings.  i.e removing the configuration data of that particular user to libreoffice.

One can find this libreoffice configuration/settings file at the following path in debian based linux like ubuntu, BOSS GNU/Linux etc.
/home//.config/libreoffice/  <-- b="">Inside this you have directory named user.  Just remove(or cut & paste to some other place) this directory and launch the Libreoffice application again.  

Note:
.config is hidden file so you first enable your file browser to see the hidden files by the short cut CTRL+h. 

How to type copyright symbol, trademark symbol etc in linux?

 As our qwerty keyboard can't accommodate all the available characters, symbols we end up with the keyboard(layout) that have the main and most widely used symbols, characters(with shift, alt key combinations).  But, in my opinion our keyboard should at least add symbols like Copyright  ©, Registered  ®, Trademark symbol ™.

Usually we do get/input these symbols from:

1. From a text editor program or from office suite(from insert symbols) like libreoffice, MS office etc.

2. From internet web pages by searching terms like "copyright symbol", "Trade mark symbol"

But, it is not possible to go every time into those application or to search with google to get/input these symbols.  So, Here is a easy way to input these symbols with your standard English keyboard layout (qwerty layout).  You have to enable some already available keyboard settings(Compose key) but not enabled by default .

So, with the help of compose key we can achieve this in our standard key board itself.

Compose key: A excerpt from wikipedia
"A compose key, available on some computer keyboards, is a special kind of modifier key designated to signal the software to interpret the following (usually two) keystrokes as a combination in order to produce a character not found directly on the keyboard. For example, striking Compose followed by ~ and then n can produce character ñ, whereas striking Compose followed by O and then C can produce the symbol ©, the copyright symbol). "

How to enable
1. In  BOSS linux(or any linux which have menu like Applications, System)
System -> preferences -> keyboard settings -> Layout settings -> options -> Compose key positions
In Ubuntu
Settings -> Keyboard -> Layout settings -> Options -> Compose key positions

2. Select your desired compose key.
   You can select any listed key(ctrl, win, capslock etc) as your compose key.  But, as we are using Linux, It is recommended to use the win(dows) key as compose key.

3.  Save the settings thats all you are done.

There are many symbols and the key combinations to produce it.  I here list few most often used symbols and its compose key combinations.  I assume win(dows) key  as the compose key.

Symbol Name	Symbol	composekey combination
Copyright	©	win+o then c
Trademark	™	win+t then m
Registered symbol	®	win+o then r
Quarter	¼	Win+1 then 4
Half	½	Win+1 then 2
3 quarters	¾	Win+3 then 4
Euro	€	win+e then =
Yen	¥	win+y then =
Pound	£	win+l then -
cent	¢	win+c then |
degree	°	win+o then o

Note:  This is for the debian based linux machines(like Ubuntu, BOSS Linux etc) which employs gnome desktop environment.  If your machine is not a debian based one or it uses other desktop environment systems(like kde, xfce etc), you have to fine where the keyboard setting is available and need to enable the settings as above.

how to view all the uninstalled packages in a debian based linux?

dpkg - > is a debian package manager command
dpkg -l - > will list all the packages with their status installed/deinstalled/removed/half-installed etc

The first 2(actually 3) letters of the output of " dpkg -l " command are significant to us, because it tells the current state of the package.  if it is
ii  - installed
rc - removed but configuration files are kept
So, " $dpkg -l | grep ^rc "
will display all the package that are removed but configuration files are still kept.

Note: if you purged configuration files of a package during removal using
"apt-get remove --purge < package_name >" then those packages will not be displayed.

For more information about dpkg :
i) man dpkg
ii) dpkg -l - > Read the first 4 lines ;-)
iii) Read this http://linuxprograms.wordpress.com/2010/05/11/status-dpkg-list/

How to install a specific version of a debian package?

Some times the debian package version which is installed in your linux box (say foo-package-x.y.xy ) is different from what version you really want(say foo-package-y.x.yx).  Assume that both the versions are available in the repository.  So, how we install the exact version we needed..? Here comes the solution, from terminal issue the following command,

$sudo apt-get install foo-package=y.x.yx
Replace the foo-package with your packagename, y.x.yx with the version (name)number you need.  Now, the package with the given version will be installed.

If you want to see all the available versions of particular debian package in the repository.. do the following,
$sudo apt-get update 
The above command updates the package index of your machine with the repository.
$sudo apt-cache show <package-name>
The above command shows the details of package, where we find version details also.

Want to install linux debian packages without internet connection..? check this out

How to install/configure skype in debian based linux?

skype:

 is a VoIP based software application which is mainly used for peer to peer phone/video call, instant messaging over internet connection in free of cost^*.  To use this one should have a valid user account with skype.  Now, skype have features like file transfer,  video conferencing also.

free of cost^*  - Only between skype accounts,  yes you can call/sms any landline/mobile phone... but with applicable call charges :(.

1. Download the latest linux version of skype from here.  Select your exact distribution like debian, Opensuse, ubuntu etc..

2. Install the downloaded package using your package manager.  I am using BOSS GNU/Linux 4.0 and it is a debian based one.  So, the following steps regarding installation is applicable to only to the debian based linux  distributions like ubuntu, BOSS GNU/Linux, linuxmint, knoppix etc.

GUI way:
Right click the downloaded skype-xy-z.deb package -> Open with gdebi package installer -> Install

Command line way:
$dpkg -i fullpath-to-downloaded-directory/skype-xy-z.deb

Once installed, as per your distribution's application classification skype menu will be placed either below internet or sound & video.  In BOSS GNU/Linux it will be placed under Internet.

3. If you have skype user account already then just use it.  If not create your user account by "Do not have user account.? create " link from the Skype GUI application.

GUI -> Graphical User Interface
BOSS -> Bharat Operating system solutions
GNU -> GNU's Not Unix
VoIP - Voice over IP(Internet Protocal)

How to lock a linux user from logging into a machine?

In some scenarios its needed to lock a user to login into his own account.  This can be achieved by many ways.

1.  GUI way

 1.1 Go to System -> Administration -> Users and Groups

 1.2 Now select the particular user from the left side, then click on the advanced settings button

 1.3 Click on the Advanced tab then tick the check box with value "Disable Account"

 1.4 To revoke follow the 1.1 & 1.2 now you can see a "Enable account" button click and enable

2. Terminal way

1. As a root user issue the following command in the terminal

    $sudo passwd -l "username of the user to lock"

How to install/use fedora 16 (verne) in Debian based linux using virutal box?

This blog post explains you how to install fedora16 (verne) in virtualbox.  Even though i do explain the things in terms of BOSS GNU/Linux 4.0(Linux distro which am using),  it is applicable to all the debian based linux distros like ubuntu etc..

1. Download the fedora linux iso CD image of installable live media from here  you will get fedora-16-i686-Live-Desktop.iso file.
2. Install virtualbox-ose from your repository using the following command in terminal
$sudo apt-get install virtualbox-ose
3. After the installation of the virtualbox the menu entry is added in Applications -> System Tools -> Virtual box click that menu entry
4. In Virtualbox click on new -> Next -> Give a name & select os type(say Fedora16, OS -Linux, fedora) -> Next -> Base memory 800 MB -> Next -> Next -> Next -> Next -> 8.0 GB Hard disk size

5. Now Click on Fedora16 (for the first time) will show a small gui that asks you for the input OS either from CD/iso image of the OS.  Search for the place where your fedora16-i686-Live-Desktop.iso file and select it.
6. Soon the OS will be booted.  Thats all but now remember now you are in live mode only.  So, if you want install the live OS into the hard drive directly.  Now click on System tools -> Install/copy to harddrive
7. Give all the options for installation like keyboard layout, country, time & partition details   etc.
8.  Thats all :)

How to generate package download script using synaptic?

This post describes how to install linux (.deb)packages into a linux machine which have no/low speed internet connection[In linux one should have a good internet connection to get connected to repository to install any new packages].  Ofcourse this will be achieved only through a another linux machine(of same distro&same version unless you know how to modify /etc/apt/sources.list and update the linux machine) that has good internet connection like your Relative's/friend's machine or a linux box in browsing center etc.  I am explaining the following thing with BOSS GNU/Linux 4.0(savir version name).

We can achieve the installation of a package into a machine with low/no internet connection

Method 1:

1. The machine in which you want to install  go  System -> Adminstration -> Synaptic Package Manager

2. Select the package which you want to install.  

 Note: Synaptic itself selects all the other dependency packages that are needed to install the package you selected.  You can see a green color tick mark, those packages are going to be installed

3. Now click on File -> Generate Download script, give a file name for the script and select path to save it.

4. Keep the resultant file with you & execute that shell script file in a machine which have the internet connection, it will downloads all the packages(.deb files) that are needed to install the packages you selected.  

5. Copy all those files to your linux machine and install through terminal as follows

$cd /path_to/deb_files/directory

$sudo dpkg -i *.deb

6. Now the packages is installed successfully thats all.

Method 2:

Another way, is install the package which have a good internet connection and copy the .deb files downloaded for that installation, use it in your system

1. First clean the archives directory

$sudo apt-get clean

2. Install the package which you want using

$sudo apt-get install <package_name>

3. copy all the .deb files from the /var/cache/apt/archives directory to your removable media(pendrive)

$mkdir /media/<your_perndrive_moutn_point>/deb_directory

$sudo cp /var/cache/apt/archives/*.deb /media/<your_perndrive_moutn_point>/deb_directory

4. Insert the pendrive in your machine and do the following

$cd /media/your_pendrive_mount_point/deb_directory

$sudo dpkg -i *.deb

Thats all the packages are installed in your machine...  This two methods are useful when you try to install huge packages like office, gimp, blender etc...

any how Methode 1 is best one as it creates the script to download the .deb packages that actually is needed to install into your machine, and it doesn't install only downloads.  

How to create a simple local apt repository?

This post is regarding debian based distros which supports .deb, so the procedures are not applicable for distros that uses .rpm like fedora, redhat etc..
Requirements:
build-essential
dpkg-scanpackages
gzip

How to do:
1. Create a directory named "repo" in your home directory.  say $mkdir /home/test/repo
2. Copy all the debs you have into the /home/test/repo
3. Open your terminal as root and do the following & change directory to /home/test/repo
    #mkdir /home/test/repo
     #cd /home/test/repo
     #dpkg-scanpackages . /dev/null | gzip -9c > ./Packages.gz

Here, '.' specifies -> present working directory
/dev/null specifies -> override file, as we not going to use override file we give /dev/null
gzip -9c>./Packages.gz -> Compresses the package details into the file Packages.gz
(Packages.gz will be created within the present working directory)
4. add the following line in your /etc/apt/sources.list file
deb file:/home/test/repo/ /
5. Update your system using apt-get update command
#apt-get update
6. Thats all now your /var/lib/apt/lists will be updated
Note: Remember now whenever you use "apt-cache search" "apt-get install" it only installs from debs inside /home/test/repo.

Tamil fonts not displayed properly in browsers.. in linux..

Once i came to know about tamil lyricist Arivumathi's blog.  So, i open it in my browser but tamil fonts are not shown properly.  The fonts are either like a rectangle or torn.  I try to see the blogpost in tamil properly, and atlast i got the following solution..

The solution is removing the Freesans, Freeserif fonts from your linux system(BOSS, ubuntu, all debian derived linux).  These fonts are in /usr/share/fonts/truetype/freefont directory.  Either remove the fonts by deleting it or copy it to some other place but not in the fonts directory.  Thats all now the blog is shown well in tamil.  the following images are

Tamil blog with tamil font rendering problem

Tamil blog after font problem fixed