Learn-Bash-Shell-Scripting/Input Output command - echo | read | echo arguments at main · Azad-02/Learn-Bash-Shell-Scripting · GitHub

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*> Input Output Command for Shell Scripting

- echo - an output command for Shell
- read - takes Input from user on terminal and stores in variable
	 SYNTAX
	 >> read <var_name>

>> read var1					# takes input on terminal and stores in var1
>> read -p "Enter Something: " var1		# prompts message before taking input

- REPLY - default variable for read command

>> read -p "Enter: "
>> echo ${REPLY}


*> Input with Command Line Argument

- aka Positional Arguments
- Are the arguments/values specified at the command prompt while running commands/shell scripts.

Script-
<<<<
#!/usr/bin/bash

echo "$1"				# first argument after running script
echo "$2"				# Second argument
echo "$3"				# third argument

<<<<

./<script.sh> 12 32 14 53 "sv a" vrd			# values must be separated by spaces
		  $1 $2 $3 $4   $5    $6

- $0 - gives name of the Script itself
     - we can use name of the script inside that script using $0

- ${>=(2 digit no.)} - to access arguments greater than 2 digit number, enter the number inside { } after $
			   - ${10} - returns 10th argument given on terminal
			   - $10 - returns values of '$1$0' together as an output.

- $# - returns number of arguments passed in terminal

- $@ - returns all the arguments passed


- $* - returns all the arguments passed