Techie Archives

Obtaining Kernel/OS information through terminal

noreply@blogger.com (Anonymous) — Mon, 27 Aug 2012 16:18:00 +0000

It is always a pleasure to have fun messing around with terminal and yet getting fruitful results from the mess. One such thing is obtaining the information regarding Kernel name, OS name, Kernel version, Kernel Release, Machine type, Processor type and so on. All these information is available to the user with the help of uname command. uname is a command line tool with which we can derive various machine and os information. Lets see the commands one by one.

To obtain kernel name,

uname -s

To obtain OS name,

uname -o

To obtain machine type,

uname -m

To obtain processor type,

uname -p

To obtain information on hardware platform,

uname -i

To obtain the kernel version

uname -v

To obtain kernel release,

uname -r

To obtain all,

uname -all

Whenever you need immediate information on your kernel or os these commands come in handy. Don't forget that the terminal is a more powerful tool which is more fast and efficient than the GUI. Go on and mess around more with your system. Because its the only you can get to know your system( "interacting a lot") and don't worry if anything happens because everything can be restored with linux. Hope the information was useful. Looking forward for more.

Find out various hardware/system information using terminal

noreply@blogger.com (Anonymous) — Mon, 27 Aug 2012 16:00:00 +0000

Whenever you are in urgent need for system information for example, you would want to know the free memory, your system configuration, hard disk information, a friend may need some immediate details and so on. Always relying on GUI tool can be inefficient because you have to search the tool and view the information. Instead there are tons of commands available out there so that you can view the system information for any particular component or as whole right from the terminal whenever you need. We shall see the commands based on the category listed one by one.

Graphics Information:

To know info about your OpenGL, graphics card use the command,

glxinfo,

Note: glxinfo may not be installed on your system, install it using

sudo apt-get info glx

To check if you have 3d rendering,

glxinfo | grep direct
grep searches for the text direct in glxinfo and returns the information in it.

To see the graphics card vendor,

glxinfo | grep vendor

To see the specifications of the graphics card model,

lspci | grep VGA

A simple 3d benchmark,

glxgears

To see the supported resolutions,

xrandr

Audio Information:

To know the information on audio controller,

lspci

lspci is a command that is used to display detailed information on PCI buses and devices connected to the system.

To know audio device information,

aplay --list-devices

Memory information:

To display the amount of RAM and swap space available and how much is being used,

cat /proc/meminfo
for more information on proc file click here

To display the amount free memory,

free -m
-m is used to display size in Mb.
for more info of free type free --help

To see the processes running in your system (like task manager in microsoft windows),

top
press C to sort data based on cpu usage.
press M to sort data based on memory usage.

HDD information:

To display the filesystem information,

df -h
-h displays data in GB.

To display the partition table,

sudo fdisk -l

Network Information:

To display info on your ethernet controller,

lspci | grep Ethernet

To display info regarding system IP and other network info,

ifconfig

Software Information:

To know the current distribution and version,

cat /etc/issue

To display package version and its dependencies,

apt-cache showpkg shutter
apt-cache show shutter | grep Version, shows only the version.

USB drives Information:

To display the list of usb devices,

lsusb

Detailed Information:

To list all PCI devices,

lspci

Overview of all hardware information in short,

hwinfo --short
To install hwinfor,

sudo apt-get install hwinfo

For more help hwinfo --help

CPU uptime can be obtained using,

uptime

You can obtain tons of detailed information regarding your system with the help of these commands. You can get more help on these commands and their uses from the web. Always there will be help when you need it. Hope, the information was helpful.

How to solve "sudo: unable to resolve host " problem ??

noreply@blogger.com (Anonymous) — Mon, 27 Aug 2012 11:04:00 +0000

Remember the previous post in which i wrote about changing your system's hostname from terminal. While many of you would have encountered a error message "sudo : unable to resolve host yourhostname" while you install or perform any task that requires root privileges. But wait, don't jump to the conclusion that you won't be able to continue your task, you can still continue with your task. There is a simple thing you have to do to get rid of this error.

When you edited the hostname file in /etc/hostname, the hostname file just contains the machine name.
You have to make the same change to the hosts file in /etc/hosts.

Viewing contents of both files in terminal:

Both the contents of the file can be viewed directly from the terminal using the commands,

cat /etc/hostname (or) hostname
cat /etc/hosts

From the above image you can see that, the hostname is aldo while the name in hosts is vms20591.

Viewing contents of both files in text editor:

To view the contents of the file in text editor type the following commands,

sudo gedit /etc/hostname
sudo gedit /etc/hosts

Note:

Remember that still you will get the error "sudo : unable to resolve host yourhostname", but just ignore it and type your password.
Also don't forget to run the command using sudo without that you can't make any changes in the hosts.

You can see the hostname varies in both files.

Making changes to the files:

In order to get rid of the error, the name in the files /etc/hostname and /etc/hosts should be the same.
Use the command previously mentioned,

sudo gedit /etc/hostname
sudo gedit /etc/hosts

After making the changes reboot the system and see if the error has been cleared.

So, the error which occurred was eliminated just by making sure the hostname in both files were the same. Hope this information was useful.

Obtaining GNOME and Unity version in Ubuntu via terminal

noreply@blogger.com (Anonymous) — Sat, 25 Aug 2012 17:55:00 +0000

Many of the users are so puzzled when they hear news about the latest release of GNOME and the features of Unity in the coming version of Ubuntu. But wait, what is the current version of these in my system of now? The answers for your questions comes with two simple commands from terminal.

GNOME version in Ubuntu:

Type the following command in terminal,

gnome-session --version

Unity version in Ubuntu:

Type the following command in terminal,

unity --version

Additional information:

To find out what option we selected (ubuntu or ubuntu 2d) during the login screen provided by display manager type the command,

echo $GDMSESSION
echo $DESKTOP_SESSION

If you selected ubuntu at the login screen then it will be displayed as ubuntu.
The login screen options when you click ubuntu circle next to your profile name,

To display the current desktop type the following command,

echo $XDG_CURRENT_DESKTOP

All these weird names up here are the environmental variables. To have a detailed view about these type the following command,

env

Hope you got benefited by the information provided. Hoping to provide more tips and tricks for the users.

How to find which window manager you are using in Linux?

noreply@blogger.com (Anonymous) — Sat, 25 Aug 2012 17:15:00 +0000

An XWindow manager(because we are talking about linux) runs on top of the XWindows system. The Window manager can be visualized like a controller that decides how the various windows in a desktop environment undergo transition. Based on the hardware capabilities of the system the graphical transitions of the windows are decided. There are various window managers available like compiz, kde, mutter, metacity, beryl and so on. Each window manager have their own way of managing the window operations.

You can have more than one window manager in your system without any worries because the kernel of the OS and GUI are separate in linux so this doesn't tamper with you underlying OS kernel. But only one window manager can run at a time. In order to find out what is the default window manager is running in your system unless you have changed it, simple steps are available.

Method 1:

The simple way is to look into the process list to find out the window manager that is running active in the system. To do that,

pgrep -l compiz |cut -d " " -f2

You can replace compiz in the above command with name of other window managers like metacity , mutter etc

Method 2:

By using the command wmctrl which is a command line utility for many window managers (linux,windows,etc) and is used to do variety of operations with the windows in the desktop.
One of the functions of the wmctrl command is to display information about the current window manager. To achieve this,

wmctrl -m

But if you get a error like wmctrl not installed, no worries install it the traditional way,

sudo apt-get install wmctrl

After the installation again type the command wmctrl -m and find the current window manager in your system.

Hope the information was useful and always don't worry when you face any difficulties with any software tool you use because there are always people out there to help.

How to check whether Compiz works fine in Linux ?

noreply@blogger.com (Anonymous) — Sat, 25 Aug 2012 15:51:00 +0000

Compiz is a composite window manager which unlike other window manager doesn't stop from normal window transitions effect rather providing visual effects when switching between windows using 3D acceleration and rendering techniques. So, how to find out if the compiz window manger that runs on your system is working good? Thats where Compiz-Check comes in. With this script you can instantly know information regarding the abilities of your system to perform under heavy 3D customization.

Why to run this test? If you happen to do so much of tweaks with your window manager or config tool you may encounter that your system crashes or programs stop working or any internal error. So, before you do anything it is good to do a test like this.

Step 1:

To obtain Compiz-Check type the following command in terminal,

wget http://blogage.de/files/70708/download -O compiz-check

Step 2:

Next convert the compiz-check script to an executable file using,

chmod +x compiz-check

Press Enter.
Run compiz check using,

./compiz-check

To know more information you can continue with y else n.

With these simple steps you can know if your system can support the graphic transitions provided by Compiz Window Manger. Hope you find this information useful.

How to obtain information about GTK+ on Linux

noreply@blogger.com (Anonymous) — Sat, 25 Aug 2012 15:17:00 +0000

GTK+ is a cross-platform widget toolkit with Graphics User Interfaces (GUI) are designed. We come across these terms when you come across an application built based on GTK+ or any other version of GTK+. When you want to change the theme of your desktop, you will see notes like these themes work for GTK+ 3x or GTK+ 2x etc. How to know what are GTK+ versions your system runs. So, for every problem or puzzle there is solution and this article might help you solve it.

Method 1:

COLUMNS=150 dpkg --list libgtk2.0-0 libgtk-3-0

Method 2:

dpkg --list libgtk2.0-0 libgtk-3-0

Method 3:

apt-cache show libgtk2.0-0 libgtk-3-0 | grep Version

Method 4:

For detailed view,

apt-cache show libgtk2.0-0

apt-cache show libgtk-3-0

Method 5:

To know the details of the packages installed,

dpkg --get-selections | grep gtk

So, hope you would be knowing how to find the GTK+ version of your system when you need to install any upcoming versions or to know if your GTK+ version is enough compatible for any software you install.

How to Install Ubuntu Tweak via PPA?

noreply@blogger.com (Anonymous) — Fri, 24 Aug 2012 18:15:00 +0000

Ubuntu Tweak is an all in one configuration tool which is exclusively designed for the Ubuntu GNOME desktop. Ubuntu Tweak is so special when its comes to functionality because with this tool you can configure your system and desktop settings which the default desktop environment provide. Ubuntu Tweak is an open source project and so it is free to download.

Ubuntu Tweak can be either downloaded from the website or installed via terminal. Since, working with terminal is fun, efficient and time saving let me guide on installing Ubuntu Tweak via PPA.

Step 1:

Launch terminal and type the following command,

sudo add-apt-repository ppa:tualatrix/ppa

Press Enter.
After you press Enter you will be prompted to enter your administrator password so type your password and press Enter.
Then you will prompted with a message in the terminal which says

You are about to add the following PPA to your system: The official Ubuntu Tweak stable repository More info: https://launchpad.net/~tualatrix/+archive/ppa Press [ENTER] to continue or ctrl-c to cancel adding it

Press Enter to continue.
Wait for the PPA to verify the source.
The PPA will be successfully added to the system.

Step 2:

Now you need to update the package manager with the command,

sudo apt-get update

Wait for the update to be completed.

Step 3:

The final step is installing Ubuntu Tweak.

sudo apt-get install gnome-tweak

After pressing Enter type your administrator password and press Enter.
You will be prompted to download certain amount of data from the web so type y and press Enter.
Wait for the installation to complete.

Step 4:

Launch the application from the terminal using the command,

nohup ubuntu-tweak &

Now, you can work your way through the tool to configure your desktop based on your needs. Ubuntu Tweak is an efficient and faster tool for the users. Hope the information would help you get started with this application.

A Quick Guide/Walkthrough for Stellarium

noreply@blogger.com (Anonymous) — Fri, 24 Aug 2012 10:06:00 +0000

Introduction:

If you happen to be fascinated by Astronomy and always wanted to see the cosmos with your surreal quality then Stellarium is the best tool which makes makes you feel that you are really seeing the planets and stars in the cosmos as if you were present there. Stellarium is an open source tool for viewing and understanding a great deal about planets and stars with stunning visuals and technical details.

Many people who are new to Stellarium would find it little bit weird on how and where to start working.Well, at first when i started using Stellarium I was puzzled more like you. Here is a very basic and a quick guide to make you get started in working your way in Stellarium.

What is the great deal about Stellarium???

Stellarium has a default catalog of over 600,000 stars.
Constellations for twelve different cultures.
Detailed information of planets and their satellites, stars, nebulae.
Easy to use interface with switching of views based on perspective.
Powerful zooming capabilities.

What can we do with Stellarium???

Missed to see the solar or lunar eclipse last time?? with stellarium you can view everything in stunning detail without having to go and out to the planetarium/observatories.
View sunrise and sunset with excellent quality.

Downloading Stellarium:

Stellarium can be easily downloaded from terminal using the command,

sudo apt-get install stellarium

Launching Stellarium:

Stellarium can be launched from the terminal using the command,

nohup stellarium &

A view of Stellarium,

Interacting with Stellarium:

There 6 different windows availabe in the Stellarium view port namely,

Location Window (press F6):

With Location windows you can set your location either by typing the location in search box(marked by rectangle) or directly entering the co-ordinates(marked by arrow).

Date/Time Window (press F5):

With Date/Time Window you can set the date and time you need and see the position of stars and planets at the time.

Sky and Viewing Option Window (press F4):

The Sky and View option window has 4 tabs of which with sky tab you can show/hide planet markers, planet boundaries and atmosphere.

With Markings tab you can change perspective from projections menu(marked by arrow), show/hide different astronomical grids and lines, show/hide constellation art, constellation lines etc.

With Landscape tab you can change the landscape on the viewport.
With option present at the bottom you can show/hide ground, fog etc.

With Starlore tab you obtain a great deal of knowledge on the stars and planets based on various cultures around the world.

Search Window (press F3):

With Search windows you search for any object or planet by typing the name in the search box provided or you can feed in the position.

Configuration Window (press F2):

With Configuration window you change various setting of stellarium based on your requirement. You would want go through some advanced guides before you tamper with the configuration.

Help Window (press F1):

Help windows provides all the shortcut keys with which will make it lot easier to work with stellarium.

Viewing info on any astronomical body:

To view the information of any planet or star or nebulae just click on it and you will see the information on the top-left of your screen.

A view of the constellations:

The glowing icons on the bar below shows that they are enabled.
The bar below is consists of basic functionalities you'll find in the different windows we saw earlier.
Basic icons includes show/hide,

Constellation art (press R)
Constellation line (press C)
Constellation labels (press V)
Equatorial grid (press E)
Azimuthal grid (press Z)
Ground (press G)
Fog (press F)
Atmosphere (press A)
Cardinal points / Directions (press Q)
Nebulae (press N)

and so on.

A view of Nebulae:

By pressing N you can see the Nebulae.
By clicking on any Nebulae you can see the information on the top-left.

A view of stars:

A view of Sirius Star.

The image shows the sirius along with its details.

A view of satellites:

Image shows the satellites which currently orbiting the Earth and their information.

A view of planets:

The image show Saturn along with its satellites.

I guess you would now be having a basic idea what Stellarium is and what it means to you. With these basic guidelines you can explore Stellarium based on your needs and get benefited by it.Hope, the information was useful.

How to make a bootable Linux USB drive via Unetbootin

noreply@blogger.com (Anonymous) — Fri, 24 Aug 2012 05:31:00 +0000

Installation of Linux OS on your system no longer requires any cd's or dvd's. All you need is a USB drive with sufficient storage space and Unetbootin. Unetbootin is an open source software that allows you to make bootable USB drives for Linux installations and it can be achieved with simple steps.

Step 1: Obtain Unetbootin

To get Unetbootin on your system type the following command from your terminal,

sudo apt-get install unetbootin

Press Enter and wait for the installation to complete.

Step 2: Formatting USB drive

After the installation of unetbootin you must format the USB drive before making it bootable.
In order to format your USB drive it should be unmounted first. So, to check the USB drive name type,

df -h

This command displays the list of drives in your system. The USB drive name, for example /dev/sdb1.
To unmount it,

sudo umount /dev/sdb1

After unmounting your USB, formatting can be done using the command,

sudo mkfs.vfat /dev/sdb1

Now your USB is ready to be made bootable.

Step 3: Creating the bootable USB

To launch Unetbootin type the command,

nohup unetbootin &

After launching Unetbootin you will find two options namely,

Distribution
Disk Image

Selecting Distribution allows you to specify the linux distribution(for example: Ubuntu 11.10) you need and it will be downloaded from the ubuntu website.
Alternatively, if you are have an image file of the linux version select Disk Image.
After selecting Disk Image, select ISO(by default) and browse the location of the linux image.
Next specify the USB drive (for example /dev/sdb1 which depends on your system).

Click Ok. Now the process will start and you will be prompted when task is complete.

Now, restart your system and select USB from your boot option and follow the on-screen instructions to install linux.

Now your all set and you can install linux along side any other OS or a standalone one. Hope, this information was useful.

10 top rated developer tools for Ubuntu 12.04 Precise

noreply@blogger.com (Anonymous) — Thu, 23 Aug 2012 07:37:00 +0000

When it comes to open source developers will love to mess up with the codes of the software tools they use in order to fix any errors in the tool, provide upgrades and contribute in the development of the tool. Here is the list of the 10 top rated developer tools which developers would like to place their hands on.

Code Blocks:

Code blocks is a cross-platform IDE which is based on a self developed plugin framework allowing unlimited extensibility. It can installed from terminal using the command,

sudo apt-get install codeblocks

Bluefish

Bluefish is a powerful editor targeted towards programmers and web-developers, with many options to write websites, scripts and programming code. Bluefish supports many programming and markup languages. Bluefish is an open source development project, released under the GNU GPL licence.It can installed from terminal using the command,

sudo apt-get install bluefish

Eclipse

Eclipse is an open source and extensible platform for development and running of any software development. It can installed from terminal using the command,

sudo apt-get install eclipse

Geany

Geany is a text editor using the GTK2 toolkit with basic features of an IDE. It was developed to provide a small and fast IDE, which has only a few dependencies from other packages. It supports many filetypes and nice features. It can installed from terminal using the command,

sudo apt-get install geany

Arduino IDE

The open-source Arduino environment makes it easy to write code and burn it to the Arduino development board. It runs on Windows, Mac OS X, and Linux. The environment is written in Java and based on other open source software. It can installed from terminal using the command,

sudo apt-get install arduino

Qt Creator

Qt Creator is a cross-platform integrated development environment (IDE) tailored to the needs of Qt developers. It provides C++ and JavaScript code editor, Integrated UI designer, Project and build management tools, Simulator for mobile UI, Support for desktop and mobile targets. It can installed from terminal using the command,

sudo apt-get install qtcreator

Idle

Idle is a simple ,yet powerful IDE for developing tools using Python. It can installed from terminal using the command,

sudo apt-get install idle

Spyder

Spyder which was previously known as Pydee is a powerful and interactive development environment for the Python language with advanced editing, interactive testing, debugging and introspection features. It can installed from terminal using the command,

sudo apt-get install spyder

Monodevelop

MonoDevelop is an open source IDE for the Linux platform primarily targeted for the development of software that uses Microsoft .NET frameworks. It currently has language support for C#, Java, Boo, Visual Basic.NET, Oxygene, CIL, Python, Vala, C and C++. It can installed from terminal using the command,

sudo apt-get install monodevelop

Anjuta

Anjuta DevStudio is a software development studio providing a number of advanced programming facilities which includes project management, interactive debugger, source editor, version control, GUI designer and so on. It focuses on providing simple user interface, yet powerful for efficient development. It can installed from terminal using the command,

sudo apt-get install anjuta

These tools will surely be of use to the programmers and developers who have a thirst to explore and exploit more of the softwares they use and will be of their aid whenever needed.

Preventing termination of an application launched from terminal

noreply@blogger.com (Anonymous) — Wed, 22 Aug 2012 16:32:00 +0000

The traditional way of launching applications was to search for the application icon either from the start menu or through the desktop icon or through any other means.

Since, Ubuntu users do anything and everything through terminal opening a GUI application too will be their concern. When a user launches an application from terminal and close the terminal because they feel so, results in the termination of the application that was just launched.
With a single command the required application can be launched from terminal and the user may close the terminal if they need and the launched application is still at their service.

Open terminal available under applications menu in dash-home.
For example, let us assume you want to launch vlc from terminal.
Type the following command in terminal and press Enter,

nohup vlc &

The nohup is a POSIX command which prevents the termination of a process/application when the user closes the terminal or issues an exit command.
After the application is launched try closing the terminal or type exit in the terminal, to your surprise you will find that the application remains in the screen whether or not terminal is present.

How to execute a C/C++ program from terminal?

noreply@blogger.com (Anonymous) — Wed, 22 Aug 2012 16:32:00 +0000

Software developers and programmers will get excited when it comes to programming especially linux users who always mess around with open source software they use. Several IDE's are available where code developers and programmers can test their programs in GUI based environment. Since, terminal users will always rely on it for any kind of task, compiling and executing programs is not going to be an exception. With some simple steps in terminal this can be achieved.

Step 1: Creating a directory for programs

Open Terminal available under application menu in dash home.
Create a folder of your wish say "sampleprograms" to store your programs,

mkdir sampleprograms

Switch to the sampleprograms directory,

cd sampleprograms

Step 2: Writing the c/c++ program

Next, we shall try a sample "hello world!!" program.
To write the c/c++ program gedit or any text editor can be used.
gedit can be invoked from using the command,

sudo gedit helloworld.c (for c program)
sudo gedit helloworld.cpp (for c++ program)

Press Enter.
After typing the program, save it and the close the editor.
Now you have finished writing your c/c++ code.

Step 3:

Compiling C program

To compile the C program type the following command,

gcc -Wall -Werror -W helloworld.c -o helloworld

Here,

gcc refers to the C compiler.
-Wall,-Werror,-W used to display the errors which may occur.
helloworld.c is the C program.
-o helloworld implies that the exe output will be created under the name helloworld.

Press Enter.
Run the program using the command,

./helloworld

Press Enter.

Compiling C++ program

To compile the C program type the following command,

g++ -Wall -Werror -W helloworld.cpp -o helloworldcpp

Here,

g++ refers to the C++ compiler.
-Wall,-Werror,-W used to display the errors which may occur.
helloworld.cpp is the C++ program.
-o helloworldcpp implies that the exe output will be created under the name helloworldcpp.

Press Enter.

Run the program using the command,

./helloworldcpp

Press Enter.

So, with the help of these simple steps programmers can compile and execute their programs right from the terminal without any trouble.

How to change your Ubuntu hostname from terminal ?

noreply@blogger.com (Anonymous) — Wed, 22 Aug 2012 09:59:00 +0000

When users install Ubuntu on their system they would want to change the system name/hostname whenever they feel so. Linux users are fond of terminal with which they accomplish any task they prefer which may be from copying a file to installing a software. So, in this article I would show you a way in which you can change the hostname from terminal.

Step 1:

Open terminal application which is available in the dash-home from your Ubuntu Unity toolbar.

Step 2:

Once you have opened terminal, to change the hostname we have to edit the hostname file available in /etc/hostname. This can be done with the following command,

sudo gedit /etc/hostname

Here gedit denotes your default text editor and so if you use someother text editor specify that instead of gedit.
Press Enter.
After you press enter you will be prompted to type your administrator password. Type the password and press Enter.
The hostname file opens in your default text editor (in this case gedit).

Step 3:

Now, just enter the desired hostname(in this case vms20591) you need, save the file and close the editor.

Restart your system.
To verify if you system name has been changed check your terminal.

In this example, the hostname has been changed from aldo to vms20591.

So, with the help of just one command from your terminal you can change/edit your hostname/system name whenever you need.