Linus praising 'C' compiler and GPL agreement...
He is looking too simple, catch him in the video right below
Thursday, July 30, 2009
Wednesday, July 29, 2009
Crazy Commands !
Many of us who love to work on Linux enjoy the privilege of using a plethora of commands and tools. Here is our effort to introduce you to a few very simple- to-use, yet enormously effective commands. The intended audience may belong to all classes of Linux users and the only requirement is to have a basic acquaintance with Linux. Our article deals with bash shell and Linux version Fedora 9, kernel 2.6.25.
1. Often, commands on the console may span many lines, and encountering a type mistake at the beginning of the command would require you to use the slow way of punching the right/left arrow keys to traverse in the command string.
Remedy: Try Ctrl+e to move to the end of the command string and Ctrl+a to reach start. It’s the fastest way to edit a Linux command line. To delete a word in the command string, use Ctrl+w.
2. Another wonder of a simple shell variable is !$. Let’s say you have to create a directory, go into it and then rename it. So the flow of commands would be:
$ mkdir your_dir
$ mv your_dir my_dir
$ cd my_dir
Remedy: Well, Linux has a shorter and quicker way:
$ mkdir your_dir
$ mv !$ my_dir
$ cd !$
!$ points to the last string in the command string. This is useful in various scenarios where the last word of command string is to be used in subsequent commands (almost with all Linux commands like vi, tar, gzip, etc).
3. Do you want to know what an ls or a date command does internally? Just run the following code to get to know the basic block of any Linux command:
$ strace -c /usr/bin/ls
strace is a system call monitor command and provides information about system calls made by an application, including the call arguments and return value.
4. What if you want to create a chain of directories and sub-directories, something like /tmp/our/your/mine?
Remedy: Try this:
$ mkdir -p /tmp/our/your/mine
5. One very interesting way to combine some related commands is with &&.
$ cd dir_name && ls -alr && cd ..
6. Now for some fun! Have you ever tried checking the vulnerability of your Linux system? Try a fork-bomb to evaluate this:
$ :( ){ :| : & };:
It’s actually a shell function; look closely and it’s an unnamed function :( ) with the body enclosed in {}. The statement ‘ :| :’ makes a call to the function itself and pipes the output to another function call—thus we are calling the function twice. & puts all processes in the background and hence you can’t kill any process. Finally ‘;’ completes the function definition and the last ‘:’ initiates a call to this unnamed function. So it recursively creates processes and eventually your system will hang. This is one of the most dangerous Linux commands and may cause your computer to crash!
Remedy: How to avoid a fork bomb? Of course, by limiting the process limit; you need to edit /etc/security/limits.conf. Edit the variable nproc to user_name hard nproc 100. You require root privileges to modify this file.
7. One more dirty way to hack into the system is through continuous reboots, resulting in the total breakdown of a Linux machine. Here’s an option that you need root access for. Edit the file /etc/inittab and modify the line id:5:initdefault: to id:6:initdefault:. That’s all! Linux specifies various user modes and 6 is intended for reboot. Hence, your machine keeps on rebooting every time it checks for the default user mode.
Remedy: Modify your Grub configuration (the Linux bootloader) and boot in single user mode. Edit the file /etc/inittab and change the default user level to 5.
I hope you’ll have some fun trying out these commands, and that they bring you closer to Linux. Please do share your feedback and comments.
1. Often, commands on the console may span many lines, and encountering a type mistake at the beginning of the command would require you to use the slow way of punching the right/left arrow keys to traverse in the command string.
Remedy: Try Ctrl+e to move to the end of the command string and Ctrl+a to reach start. It’s the fastest way to edit a Linux command line. To delete a word in the command string, use Ctrl+w.
2. Another wonder of a simple shell variable is !$. Let’s say you have to create a directory, go into it and then rename it. So the flow of commands would be:
$ mkdir your_dir
$ mv your_dir my_dir
$ cd my_dir
Remedy: Well, Linux has a shorter and quicker way:
$ mkdir your_dir
$ mv !$ my_dir
$ cd !$
!$ points to the last string in the command string. This is useful in various scenarios where the last word of command string is to be used in subsequent commands (almost with all Linux commands like vi, tar, gzip, etc).
3. Do you want to know what an ls or a date command does internally? Just run the following code to get to know the basic block of any Linux command:
$ strace -c /usr/bin/ls
strace is a system call monitor command and provides information about system calls made by an application, including the call arguments and return value.
4. What if you want to create a chain of directories and sub-directories, something like /tmp/our/your/mine?
Remedy: Try this:
$ mkdir -p /tmp/our/your/mine
5. One very interesting way to combine some related commands is with &&.
$ cd dir_name && ls -alr && cd ..
6. Now for some fun! Have you ever tried checking the vulnerability of your Linux system? Try a fork-bomb to evaluate this:
$ :( ){ :| : & };:
It’s actually a shell function; look closely and it’s an unnamed function :( ) with the body enclosed in {}. The statement ‘ :| :’ makes a call to the function itself and pipes the output to another function call—thus we are calling the function twice. & puts all processes in the background and hence you can’t kill any process. Finally ‘;’ completes the function definition and the last ‘:’ initiates a call to this unnamed function. So it recursively creates processes and eventually your system will hang. This is one of the most dangerous Linux commands and may cause your computer to crash!
Remedy: How to avoid a fork bomb? Of course, by limiting the process limit; you need to edit /etc/security/limits.conf. Edit the variable nproc to user_name hard nproc 100. You require root privileges to modify this file.
7. One more dirty way to hack into the system is through continuous reboots, resulting in the total breakdown of a Linux machine. Here’s an option that you need root access for. Edit the file /etc/inittab and modify the line id:5:initdefault: to id:6:initdefault:. That’s all! Linux specifies various user modes and 6 is intended for reboot. Hence, your machine keeps on rebooting every time it checks for the default user mode.
Remedy: Modify your Grub configuration (the Linux bootloader) and boot in single user mode. Edit the file /etc/inittab and change the default user level to 5.
I hope you’ll have some fun trying out these commands, and that they bring you closer to Linux. Please do share your feedback and comments.
Wednesday, July 15, 2009
Forget Computer Hacking, your BRAIN may be the next !
I'm really shocked with this article published in the Times Group.
IT sectors are busy fighting with the word "HACK" nowadays, If computer hacking not be cured yet, What about saving brain ?
According to the experts, Hackers who can easily break into computers are giving researchers sleepless night as they hear that someday, Human mind get hacked as well.
In the last few years researchers have developed technologies that makes it possible to use thoughts to operate computers, maneuver a wheelchair or even use Twitter, all without lifting a finger. But as neural devices become more complicated and go wireless, some scientists say the risk of "BRAIN HACKING" should be taken seriously.
So what to say on this, Is it possible ?
Three questions arising here,
1. Why anyone would want to hack other's brain ?
2. What will be the wireless range ?
3. What will be the anti-hacking software then, and where to install it ?
IT sectors are busy fighting with the word "HACK" nowadays, If computer hacking not be cured yet, What about saving brain ?
According to the experts, Hackers who can easily break into computers are giving researchers sleepless night as they hear that someday, Human mind get hacked as well.
In the last few years researchers have developed technologies that makes it possible to use thoughts to operate computers, maneuver a wheelchair or even use Twitter, all without lifting a finger. But as neural devices become more complicated and go wireless, some scientists say the risk of "BRAIN HACKING" should be taken seriously.
So what to say on this, Is it possible ?
Three questions arising here,
1. Why anyone would want to hack other's brain ?
2. What will be the wireless range ?
3. What will be the anti-hacking software then, and where to install it ?
Is Sun's demise = failure of the Open Source model ???
Let's Check it out !
There is a feeling that Sun's demise also means the failure of Open source model. But this isn't correct. Sun failed due to the problems it inherited.
Laurent Lachal, director, open source research, Ovum notes, "Oracle is better positioned to make money out of this business than Sun was, Sun didn't make much of its open source software because software business-irrespective of the software being open source or not.
"Its tough to make money in any business these days, let alone a profitable s/w business. There are small number of companies that have built successful open source business. But REDHAT proves that it is possible to build a successful open source business".
By: Jim Zemlin, executive director, The Linux Foundation
There is a feeling that Sun's demise also means the failure of Open source model. But this isn't correct. Sun failed due to the problems it inherited.
Laurent Lachal, director, open source research, Ovum notes, "Oracle is better positioned to make money out of this business than Sun was, Sun didn't make much of its open source software because software business-irrespective of the software being open source or not.
"Its tough to make money in any business these days, let alone a profitable s/w business. There are small number of companies that have built successful open source business. But REDHAT proves that it is possible to build a successful open source business".
By: Jim Zemlin, executive director, The Linux Foundation
!!! ORACLE GRAVITY PULLS IN SUN !!!
"Sun's failure is not the failure of Open Source"
Michel Tiemann (pic), The president of Open source affairs ar REDHAT Inc. addressed a press conference: A Summary -->
It will be totally a Culture Shock for Sun Developrs at Oracle, Sun was known as the open source company but Oracle doesn't have that reputation. He told that Oracle has been contributing to the Linux kernel for quite some time.
Open source is a great way to grow a value of technology asset, so perhaps Oracle will directly attack to Java.Customers are looking for heterogeneous environments and they find Redhat and Oracle better than Microsoft, while Redhat is leading open source company, Oracle offers a mix.
--> David Axmark, co-founder, MySQL Database:
The whole idea with FLOSS software is that it doesn't matterwho owns it even remotely as much as it does for closed source software. So they (customers-users) can continue to use MySQL whatever happens. And there are still tons of good MySQL support people at Sun, so there is no problem buying support from Sun.
(I think Axmark has a strong point in this)
--> Monty Widenius, co-founder, MySQL Database:
"We would be happy to cooperate very closely with Oracle but we are not likely to join. After working for a big company like Sun, we enjoy the extra freedom and benefits we get in a smaller company. Another thing is that I don't think Oracle can match the benefits of the hacking business model we have been using."
(Hmmmm...Kool down Mr. Widenius)
Fight Club (Mandriva vs Windows 7)
The war has begun, The final release of Windows 7, the latest (and greatest?) version of windows is just months away.
A face off between Mandriva Linux 2009.1 spring and the release candidate of Windows 7 which is freely available on Microsoft's site (FREELY)!!!
I read the article quite many times repeatedly and can extract an idea that gradually Microsoft is moving towards open source business, but it will be too early to say this.
In Windows 7 Microsoft tried a lot for GUI support and must say, They succeeded !!!
Here I provide Ratings b/w them:
__________________________________________
Ratings windows Mandriva 2009
__________________________________________
Looks 8 5
Speed 16 mins+user 11 mins+user
Function 4 7
Codec support 8.5 9
h/w support 9 9
__________________________________________
So, guyzzz it's upon you to judge :-))
My views:
I use Linux O/S with a real flair, but judging on the fact,
Don't be Fooled!!! Mandriva any day!
Though Windows looks great but does nothing else, we (RHCEs) are command line experts and say, GUI are for idiots :-(
So, if you need good version of Linux kernel, other than Fedora they can also go with Mandriva spring edition.
Thursday, July 9, 2009
Frauds beware, software can see through disguise !
A cutting-edge face recognition software could revolutionize security systems, especially if it can see through disguises, according to the latest research.
Every face has special features that define that person, yet faces can also be very similar, explained Ling Huang from from Florida Atlantic University (FLA)in Boca Raton. That makes computerized face recognition for security and other applications an interesting but difficult task. however, powerful techniques have so far required powerful computers.
Now, Huang and colleagues Hanqi Zuhang and Salvotore Morgera, have applied a one dimensional filter to the two dimensional data from conventional analysis, such as the Gabor method this allows them to reduce significantly the amount of computer power required without compromising accuracy. It can even see through certain types of disguises such as facial hair and glasses.
The team tested the performance of their new algorithm on a standard database of 400 images and 40 subjects. They found that their technique is not only faster and works with low resolution images, such as those produced by CCTV cameras, but also solves the variation problems caused by different light levels and shadows, viewing directions, pose and facial expressions.
Face recognition software has been in development for many years. However, for biometric authentication at border crossings, for access to buildings, for automated banking and crime investigation.
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