Basic Linux Shell Scripting

What is Kernel ?

The kernel is a computer program that is the core of a computer’s operating system, with complete control over everything in the system.

What is Shell ?

A shell is a special user program that provides an interface for users to use operating system services. Shell accepts human-readable commands from a user and converts them into something which kernel can understand. It is a command language interpreter that executes commands read from input devices such as keyboards or from files. The shell gets started when the user logs in or start the terminal.

What is Linux Shell Scripting?

A shell script is a computer program designed to be run by a Linux shell, a command-line interpreter. The various dialects of shell scripts are considered to be scripting languages. Typical operations performed by shell scripts include file manipulation, program execution, and printing text.

What is #!/bin/bash?

This is the first line from bash scripts. The name of this line is: she-bang‘(shabang), hashbang. This derives from the concatenation of two tokens, sharp(#) and bang (!). This combination of tokens will be present at the beginning of a script. It will specify which specific interpreter should be used to execute commands.

Can we write #!/bin/sh as well?

Yes, #!/bin/sh can be used as well instead of #!/bin/bash.

Write a Shell Script that prints I will complete #90DaysOofDevOps challenge?

Write a Shell Script to take user input, input from arguments and print the variables.

An Example of If else in Shell Scripting by comparing 2 numbers

Thank you for reading.

Bikram Chatterjee