What is a Unix shell?

Posted: March 28th, 2010 | Author: | Filed under: Shell scripting | No Comments »

A Unix shell is a command-line interpreter (see shell) and script host that provides a traditional user interface for the Unix operating system and for Unix-like systems. Users direct the operation of the computer by entering command input as text for a command line interpreter to execute or by creating text scripts of one or more such commands.

The most prominent Unix shells are the Bourne shell, which is the original Unix command line interpreter for system control and user sessions, and the C shell, a shell primarily used for interactive user sessions in the line of Unix-derived operating systems based on the Berkeley Software Distribution (BSD). Both shells have been used as coding base and model for many derivative and work-alike shells with extended feature sets.

My favorite is KSH (Korn shell), second it’s BASH which is the most shell used and it’s basic for linux systems.

Reference: http://en.wikipedia.org/wiki/Unix_shell

What is a shell scripting?

Posted: March 28th, 2010 | Author: | Filed under: Shell scripting | No Comments »

A shell script is a script written for the shell, or command line interpreter, of an operating system. It is often considered a simple domain-specific programming language. Typical operations performed by shell scripts include file manipulation, program execution, and printing text, etc.

Many shell script interpreters double as command line interface, such as the various Unix shells, Windows PowerShell or the MS-DOS COMMAND.COM. Others, such as AppleScript or the graphical Windows Script Host (WScript.exe), add scripting capability to computing environments without requiring a command line interface. Other examples of programming languages primarily intended for shell scripting include DCL and JCL.