Shell Script

Notations used in Shell Scripts

Positional parameters: $0, $1, $2, ...

These variables hold the values of command-line arguments passed to the script when it is executed.
$0: Contains the name of the script or the command used to invoke the script. It represents the script's own name
$1, $2, $3... : Hold the values of the command-line arguments passed to the script. $1 corresponds to the first argument, $2 corresponds to the second argument, and so on. The number after the $ indicates the position of the argument.

Example:

Consider the following script named "myscript.sh"


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#!/bin/bash
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echo "Script name: $0"
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echo "First argument: $1"
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echo "Second argument: $2"

If you execute the script with command-line arguments like this:


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$ ./myscript.sh arg1 arg2

The script will output:


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Script name: ./myscript.sh
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First argument: arg1
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Second argument: arg2