Techspace

Working with LEX & YACC programs in Ubuntu.

You might have wondered why LEX and YACC programs will not work in LINUX even if have written your program correctly. Well, no need to worry. Just a simple 3-4 steps will successfully execute your programs.

Steps goes like this :---

Go to terminal and enter the following command. sudo apt-get install build-essential

Then type sudo apt-get install flex(For lex programs).

Again type sudo apt-get install bison(For yacc programs).

If you carry out above process, you will be done with configuring FLEX and BISON. Now you will be able to execute your lex and yacc programs.

Thank you :)

Installation guide Of OpenGL in Windows

Download Microsoft Visual Studio 2008 and select Visual Studio C++ during installation.

After installing, you have to install GLUT.

GLUT can be downloaded from

http://www.mediafire.com/?ij1m9em7xdy

Configuring GLUT:--

C:\Program Files\Microsoft Visual Studio 9.0\VC\bin---->Paste glut32.dll file

C:\Program Files\Microsoft Visual Studio 9.0\VC\include---->Paste glut.h file

C:\Program Files\Microsoft Visual Studio 9.0\VC\lib---->glut object library file glut32.lib

C:\Program Files\Microsoft SDKs\Windows\v6.0A\bin--->-glut32.dll

C:\Program Files\Microsoft SDKs\Windows\v6.0A\Include---->glut.h

C:\Program Files\Microsoft SDKs\Windows\v6.0A\Lib--->glut32.lib

C:\Program Files\Microsoft SDKs\Windows\v6.0A\Include\gl---->glut.h

C:\WINDOWS\system32---->glut32.dll

Debug and Run the code. If any problem or clarification regarding the installation of OpenGL or GLUT, please post it in comment panel or mail me to srikanth.gundaz@gmail.com.

Thank you. :P :)

Installation guide of OpenGL API in Ubuntu/Fedora

Many would have installed OpenGL, an API(Application Programming Interface) for writing applications that produce 2D and 3D Computer Graphics.

Installation of OpenGL in Linux platform is different and installation in WINDOWS is different. So, some set of steps has to be followed while installing OpenGL in LINUX platform.

Steps goes like this:--

First we need to install the IDE(Integrated development environment). Here, we use CODE::BLOCKS IDE. To install, open the terminal and type the following command.

sudo apt-get install codeblocks

What actually happens when u execute this command?

The application name specified in the command will be checked in the repository and then the application gets installed by downloading the installation files from the internet or from the pre-installed folder which contains installation files.

Now, IDE is ready but we have to install GLUT(OpenGL Utility Toolkit). We have to pay for installing GLUT but FREEGLUT available in the net. So, we can install this by the following 2 commands. Enter these following commands in the terminal.

sudo apt-get install freeglut3

sudo apt-get install freeglut3-dev

GLUT files will be installed in /usr/include/GL/ directory.

Once the API is successfully installed, next step is to configure it.

Steps:--

Go to Applications-->Programming-->Code::Blocks IDE

Then, go to Settings-->Compiler and debugger.

Open Linker settings tab. Then, in the bottom, you can see the ADD button. Click on Add button and then type glut and click on ok. In the same way, type as GLU and GL in Linker settings tab.

FreeGLUT is installed now.

Now API is ready to execute the programs.

Type the program and if you come up with any problem saying cannot find lXxf86vm, then no need to worry. Just go to terminal and type the following command and you are done with that.

sudo apt-get install libXxf86vm-dev

Now, run the program and it must execute.

Any problem or clarifications regarding this post can be posted in the comment panel or email to srikanth.gundaz@gmail.com.

Thank you. :)

How to code OpenGL programs on Ubuntu?

After searching for a long time, I've finally found a solution on how to use Code::Blocks to work with OpenGL APIs.

Code::Blocks is an IDE just like Visual Studio on Windows. Install Code::blocks from the Ubuntu Repository by typing this at the terminal.

sudo apt-get install codeblocks

Once you're done, you need to download files that support OpenGL. You need to install the following package for it to work.

freeglut3 & freeglut3-dev - For GLUT Library. It installs some files into your /usr/include/GL/ folder.

libsdl1.2-dev - For SDL Library. It installs some files into your /usr/include/SDL/ folder.

To install these type the following at the terminal.

sudo apt-get install freeglut3

sudo apt-get install freeglut3-dev

sudo apt-get install libsdl1.2-dev

Once you're done with this library installation, you should tell the Code::Blocks to link to the correct library for it to be able to execute GLUT/SDL programs. This is how you do it.

1. Open Code:Blocks (You can find this in Applications -> Programming -> Code::Blocks or type codeblocks at your terminal)

2. Go to Settings -> Compiler and Debugger.

3. Open Linker Settings tab. And under "Link Libraries" add "glut" for GLUT, "SDL", "GLU" and "GL" for SDL.

4. Click OK and you're now done with it. Now your CodeBlocks should be able to compile OpenGL - GLUT/SDL code. Compile a running code to check.

If it didn't work then please comment on this post so that i can help you.

PS: The whole procedure is to install both GLUT and SDL Libraries. But it is always any one, either GLUT or SDL, that is used. So if you want to install any one of them then skip the instructions that are for the other one.

Lucid Lynx

Today, the most of the users and clients use LINUX operation systems. Nowadays, a lot and lot of LINUX flavours has been developed and released by different companies but still the development of the OS is still in progress. Even, most of the users and clients(as of now) use LINUX, still in the corner of their minds, they think that WINDOWS is better than LINUX. This feel comes to mind only when he/she fails to use a software in the LINUX or feel difficulty in using the command lines or the user interfacing criteria's. This is the foremost feel/think which the user gets when he/she suffers or find difficult in using LINUX. So, the development/upgradation of the LINUX OS's is more essential to make sure that none of the user finds difficult in using LINUX. Same thing is being done by a famous LINUX OS developing company named UBUNTU.

Currently, this company has a UBUNTU 9.10(Karmic Koala) as its current stable version of LINUX. And the upcoming version named UBUNTU 10.04(Lucid Lynx) has a greater development/enhancement of the OS.

Change in the features of LUCID LYNX:--

Schedule for release on 29 April 2010.

We have a Gnome version-2 as the default environment for Ubuntu 9.10, we still have Gnome2.x only as the default environment in LUCID LYNX too.

Gnome 3 will be developed for a stable use and will be released as a Long Term Support version(LTS) or in the next version of Ubuntu. But as of now, Ubuntu 10.04 has sticked with Gnome2.x as its Long Term Support version since the Gnome 3 is under development and testing.

Working on the enhanced version of GTK+ that will include RGBA support.(A=Alpha , meaning Transparency). This means, there might be inclusion of Transparency or a high quality desktop viewing as that of WINDOWS 7. Right now, an application named ADVANCED DESKTOP EFFECTS is used as a tool for improvement in the effects of the desktop but we didn't have a transparency effect in that. May be GTK+ includes transparency effect.(Have to wait and explore after its stable release).

Installation time will be reduced since downloads and installation will happen in parallels and hence a great shorting of the installation time. In Ubuntu 9.10, first the download of installation files will happen and then the installation will be carried out. So, apparently, the time needed for the installation by LUCID LYNX is pretty much lesser than that of earlier versions.

PIDGIN(IM[Internet Messenger] client) may be removed from 10.04 and they might upgrade and setup the EMPATHY as the default IM client.

The most worrying part in 10.04 is, it might not contain GIMP(Same as that of ADOBE PHOTOSHOP). This is a major loss to Ubuntu users. I really dont know why, Ubuntu developers are going to take out GIMP.

Well, these are some features which will be included in UBUNTU 10.04 LUCID LYNX. Till the stable version is released, all the things should be considered as tentative.

Comments are whole-heartedly welcomed. Thank you :)

Blogger in Draft

http://draft.blogger.com

I'm not sure how many of you know about this. I've been using it from quite sometime now.

Blogger in draft not so different from Blogger but with added functionalities. People behind blogger add new features to blogger in draft before releasing them to rest of the world. It has a better editor with some great features. All that you need to do is to log in to draft.blogger.com instead of using blogger.com and you can switch between them anytime.

You can find more FAQs here on their blog.

Using third-party templates has always been an headache in blogger, but not anymore. Use Blogger in Draft's new feature to design your own template, released just today. The best part is, it is highly customizable. You can choose between 4 of the templates (as of now), and you can customize it with hundreds of cool backgrounds and a variety of layout designs in adjustable size. You can change just about everything.

There are some more features that you may like in Blogger in Drafts. The WYSIWYG editor is more powerful and handling pictures and videos is very simple.

Snapshot below can help you find the template design feature.

"Template designer", new option under Layout Tab

Here are a couple of snapshots of what they offer at their template designer.

Basic Screen of Blogger Template Designer(click to expand)

click to enlarge

This is the secret behind my new theme ;). Kewl ain't it?

Inverse Graphing Calculator

This is something I found just now.

http://www.xamuel.com/inverse-graphing-calculator.php?phrase=Racing+Infinity

The above link takes you to Xamuel's latest Inverse Graphing Calculator. It gives you the equation to your desired text. It gives equation which when plotted on a graph will give you the text you entered. Click on the link above. I did not try to prove its genuineness. Try if you want but don't forget to post back your comments here later.

Here is a snapshot of it.

SOLUTION TO CHANGE OR GET RID FROM THE DEFAULT KEYRING PASSWORD PROMPT

You might have got bugged by entering the password while using the EMPATHY in UBUNTU 9.10 bcoz of its password prompt. And there can be a case in which you might have forgotten your authentication password. So, you might not be able to use EMPATHY since it asks for DEFAULT KEYRING PROMPT. You will ask Is there any way to get rid from that or to change the DEFAULT KEYRING password. Answer is yes. There is a simplest way to change or to get rid from the DEFAULT PASSWORD prompt.

Steps goes like this:--

Go to Applications menu and Accessories and choose Password and Encryption Keys.

Then a new window will be opened and here you can see only one content. Passwords: login.

Right click on that Passwords: login and choose Change password.

Now, you may get one doubt regarding this. This option is to change the password but how can i get rid from password prompt?

Here is the solution for that.

Type the old password and do not enter the password in the PASSWORD and CONFIRM PASSWORD tabs. Just leave it blank and then click on CHANGE.

That's it. From now on, Ubuntu would not prompt for the DEFAULT PASSWORD KEYRING.

What if you have forgotten the old password? No need to worry. Just right click on Passwords: login and then choose Delete. That's it. No more problem.

Isn' this is simple and easy to get rid or to change the DEFAULT PASSWORD PROMPT by UBUNTU 9.10? Post your replies as comments in comment's panel.

Thank you :P

How to make Ubuntu to not ask for password when you do sudo?

There are some commands in ubuntu that do not work without 'sudo'ing. Like while creating a text file you use 'sudo vi' instead of just 'vi' and then you had to enter password again. This is the security scheme used by Ubuntu to save your files from external attacks.

If entering password for every command is uninteresting and frustrating, then here is a solution to it.

Step1 -

Open your terminal and type the following -

sudo visudo

Now enter your password and visudo will appear. Visudo is an editor used to safely edit this file called - sudoers. sudoers is a file located in /etc directory and it contains the information of who can use sudo.

Step2 -

At the end of the file add the following line

%username ALL=(ALL) NOPASSWD: ALL

Make sure you replace username with the username of your account and don't forget to retain the '%' symbol at the beginning. Save & Exit.

That's it. You're done. Though this makes everything easy, it is not so recommended. By enabling this, you will be exposed to attacks since no password is required. There is an alternate way. You can specify all the commands in the statement itself so that only those commands do not need passwords. An example is here -

%username ALL=(ALL) NOPASSWD: /bin/kill, /bin/ls, /usr/bin/lprm

With this, you ll be able to use only kill, ls and lprm commands without password.

Solution for Update Manager Broken filter Error

The Update Manager is used for updating the Ubuntu and its resources. If u have to Update Ubuntu, then its very easy using Ubuntu.Just go to Sytem-->Administration-->Update Manager. Then select all the software and library packages which you want and click on Install Updates. It will ask for Password Authentication. Enter the password and then all work will be carried out by Ubuntu for its Updation. But if there is something wrong with Update Manager, It shows an error as shown. You have one broken package on your server. Use the "Broken" filter to locate it. You can ask, Will this create any problem for updation? Answer is Absolutely No. This will not make any effect on the updation but there one or the other resources liked to that broken filter may not get updated. So now, lets see how to get rid of this Broken filter error.

Steps that has to be carried out are as shown below:--

Open Synaptic Manager.(System-->Administration-->Synaptic Package Manager)

Go to Edit--> Fix Broken Packages from the menu.

Again Go to Edit menu and choose Apply Marked Changes or press Ctrl + P.

Click on Apply. Some packages will be downloaded and a perfect Update Manager will be installed.

Now open Update Manager and you will not be shown any error regarding the broken filter. Update Manager problem solved.

But during update, you should be very carefull while selecting the packages which should be updates. For this, you should read this post.http://srikanthgundaz.wordpress.com/2010/01/14/can-update-cause-problem/

Thank you.