Sunday, May 25, 2008

What Python is?

If any person had a little bit knowledge of programming then he or she is definitely heard about the Python.In this post i am going to told you about what python is, when it was developed, reasons behind development and many other things.

Python is an interpreted, object-oriented, high-level programming language with dynamic semantics. Its high-level built in data structures, combined with dynamic typing and dynamic binding, make it very attractive for Rapid Application Development, as well as for use as a scripting or glue language to connect existing components together. Python was first developed by Guido van Rossum in 1991.Like Perl, Python source code is now available under the GNU General Public License (GPL).

Python supports modules and packages, which encourages program modularity and code reuse.Python is most preferred by programmers because of the increased productivity it provides. Similar to perl it has no compilation stage due to which the edit-test-debug cycle is incredibly fast. Python can easily run on Windows, Linux/Unix, Mac OS X, OS/2, Amiga, Palm Handhelds, and Nokia mobile phones. Python has also been ported to the Java and .NET virtual machines. In addition with perl, python is also similar to java.

A person having basic knowledge of both can easily learn python.In addition to all of these python provides you advanced programming features such as generators and list comprehensions, automatic memory management frees you from having to manually allocate and free memory in your code and many other features. It is assumed that python is great for both shell and web scripting. Now a days it makes its way in way into every facet of computing from Google to video games.

What Perl is?

If any person had a little bit knowledge of programming then he or she is definitely heard about the PERL.In this post i am going to told you about what perl is, when it was developed, reasons behind development and many other things.

Perl is a dynamic programming language which was developed by Larry Wall in 1987.Actually perl was developed 4 years before the development of LINUX.Perl stands for Practical Extraction and Reporting Language, the meaning of this expansion is that perl is an interpreted programming language with a huge number of uses, libraries and resources.The main reason that is assumed behind the development of PERL is that Mr Wall was unhappy with the functionality of sed, C, awk and the Bourne Shell that these languages offered.

Then after this they decide to made a language that contains advantage of all these languages. The main popularity that the perl earned when it is used as a language for writing server-side scripts for web-servers. In addition to this perl is also used for system administration tasks, managing database data, as well as writing GUI applications. Perl also consists of various capabilities like it can store strings and data structures that are unlimited in size, nested to any depth, it has powerful syntax and built-in functions, it also provide support for namespaces, classes, and objects, it can run on almost any platform imaginable and has relatively portable and secure code.

As all we know perl is an interpreted language so no compilation is needed here. The programs that are written in Perl are known as Perl scripts and the term perl program refers to the system program named perl for executing Perl scripts. Now if you had any previous experience on shell scripts or awk or sed or similar (Unix) utilities for various purposes, you will find that you can normally use Perl for those and many other purposes, and the code tends to be more compact.

Saturday, May 24, 2008

What Shell Script is?

Hello friends in this post i am going to tell about the shell script,what
exactly shell script means and many other things about shell script.

As a computer programmer we definitely aware of the term Shell Script,what exactly shell script means. First of all before understanding what the shell script is, we must know what is shell. Actually in early days of computation instruction are provided using binary language, which is difficult for all of us, to read and write.So to overcome this problem a special program which is known as SHELL used in the operating systems. Shell accepts instructions or commands from you in English and pass it to the kernel if it is valid.

In other words we can also say that Shell is a user program or it's environment provided for user interaction.Shell is an command language interpreter that executes commands read from the standard input device (keyboard) or from a file.Now we come on to the shell script.Shell Script is series of command written in plain text file. It means you can store a sequence of n commands in the text file in the order in which you want to execute them.After entering all commands you can tell the shell to execute this text file instead of entering the commands. This text file is known as Shell Script.

Shell Script is almost similar to batch files in MS-DOS but shell scripts are more powerful then batch files.Now the main question that arises here why to use shell script, the answer to this problem is very simple by using shell script you can take input from user, file and output them on screen, also useful in to create your own commands, save lots of time,also help you in to automate some task of day today life and with the help of shell script system Administration part can be also automated.

What Linux is?

Hello friends this is my first post and in this post you found various interesting points about LINUX. Hope you enjoy the reading.

It is definite that every computer programmer or a software engineer is definitely aware of Linux.Linux is Unix like operating system and it is developed by Linus Torvalds. The main reason behind the development of Linux is to provide personal computer users a free or very low-cost operating system comparable to traditional and usually more expensive Unix systems. Within the next few years of its developments its made image like of a very efficient and fast performing operating system.

Today LINUX is freely available in the market while you had to pay for other operating systems. The biggest advantage of using LINUX is that you can adjust your LINUX operating system as per your requirement because when you get Linux you will also get source code of Linux, so you can modify OS according to your requirement.Unlike Windows and other proprietary systems, Linux is publicly open and extendibles by contributors. Linux provides you poratble operating system interface that means any program that is written on LINUX can be easily ported to the other operating system.

In addition to all these things it also offers many Free Software applications, programming languages, and development tools etc.When we compare LINUX and UNIX then they almost have all the same features like Unix, Linux is also written in C,both of them are Multi-user/Multitasking/32 or 64 bit Network OS, both of them had rich Development/Programming environment.The only difference between Unix and Linux is that Linux is open source while Unix is not open source.