A shell script is a computer program designed to be run by the Unix/Linux shell which could be one of the following: The Bourne Shell; The C Shell; The Korn Shell; The GNU Bourne-Again Shell; A shell is a command-line interpreter and typical operations performed by shell scripts include file manipulation, program execution, and printing text. A full PDF and online tutorial is available at steve-parker.org/sh/sh.shtml v1.1 - 7 Aug 2007 UNIX / Linux Shell Cheat Sheet File Manipulation Test Operators Unix Shell Programming - by Dinesh Kumar S Chapter 5 A Beginning to Shell Scripting Rule to write Shell script: Write Script: Create a shell script using a text editor ( Emacs ). Save the script file as, .sh .bash Example: emacs my_first_script .bash emacs my_first_script .sh Write Script Give Execute permission to user Run Script Shell script programming has a bit of a bad press amongst some Unix systems administrators. This is normally because of one of two things: • The speed at which an interpreted program will run as compared to a C program, or even an interpreted Perl program. • Since it is easy to write a simple batch-job type shell script, 1. Programming Language Constructs: Shell provides powerful constructs using which exiting commands can be used to frame the job sequences or develop new utilities. 2. Shell Scripts: Shell commands and constructs are stored in a file, which can later be used to execute these commands like a program. This file is generally called shell script. 3. Output the Program's Purpose We can use the Echo command to output what the program will do. When we have more than one Shell Script in a folder, we can first display on the monitor what the software will do on our computer before answering the user's prompts. This is good programming etiquette. Introduction Shell Script A shell script is a computer program designed to be run by the Unix shell, a command-line interpreter. The various dialects of shell scripts are considered to be scripting languages. MO101: Python and Shell Script - Vladimir Paun There are several shells are available for Linux systems like -. BASH (Bourne Again SHell) - It is most widely used shell in Linux systems. It is used as default login shell in Linux systems and in macOS. It can also be installed on Windows OS. CSH (C SHell) - The C shell's syntax and usage are very similar to the C programming language. A working knowledge of shell scripting is essential to anyone wishing to become reasonably proficient at system administration, even if they do not anticipate ever having to actually write a script. Consider that as a Linux machine boots up, it executes the shell scripts in /etc/rc.d to restore the system configuration and set up services. • You have an idea about programming and you want to start coding some shell scripts. • You have a vague idea about shell programming and want some sort of reference. • You want to see some shell scripts and some comments to start writing your own • You are migrating from DOS/Windows (or already did) and want to make "batch" processes. shell process, so they inherit your environment but do not have access to your local variables • Running a script as a command requires execute permission for the script file and that the shell can find the script file • To execute a script file in the current shell process instead of a ch