This repo contains some basics to advanced concepts of The Linux BASH. It also has some utility bash-scripts which can be used to make life easier.


Conventions ::

Lets first discuss about the conventions of writting bash-scripts.

The very first line should be a shebang line (https://en.wikipedia.org/wiki/Shebang_(Unix)).

#!/bin/bash

Followd by Auther Description, Data created , Date Modified , short description & usage. Like below :

#AUTHOR : Arnob kumar saha

#Date Created : 06-11-2021

#Last Modified : 10-12-2021

#DESCRIPTION : write a one-liner comment to express the overall functionality of this script.

#USAGE : How to use this script

After these lines , All the variables that have been used in the script should be declared.

age=23

x=something

Then the actuall script starts.

You should know ::

  1. Bash variables are untyped. There is nothing like integer, string or bool variables in bash. You can imagine them as a bunch of characters stored in memory, with no special meaning. but, depending on context, Bash permits arithmetic operations and comparisons on variables. The determining factor is whether the value of a variable contains only digits.

  2. It support arrays, which is a list of varibles.

  3. List of scpecial characters : whitespaces like newLine, space, tab, carriagereturn etc. ' " \ $ # = [ ] { } ( ) ! < > | ; & ` * ? ~

  4. use the below syntax for multiline commenting in bash:
    : '
    first line
    second line
    ....
    '
    the space between the colon and singleQuote is important.

  5. To run script, you may have to give the execution permission, using command like ,
    chmod 744 filename


Contents (in serial order) ::

basics
conditions
rules
loops