How to use positional parameters

From Linux Shell Scripting Tutorial - A Beginner's handbook
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All command line parameters ( positional parameters ) are available via special shell variable $1, $2, $3,...,$9.

How Do I Access Command-Line Arguments

Create a simple shell script called cmdargs.sh:

#!/bin/bash
echo "The script name : $0"
echo "The value of the first argument to the script : $1"
echo "The value of the second argument to the script : $2"
echo "The value of the third argument to the script : $3"
echo "The number of arguments passed to the script : $#"
echo "The value of all command-line arguments : $*"

Save and close the file. Rut it as follows:

chmod +x cmdargs.sh
./cmdargs.sh bmw ford toyota

Sample outputs:

The script name : ./cmdargs.sh
The value of the first argument to the script : bmw
The value of the second argument to the script : ford
The value of the third argument to the script : toyota
The number of arguments passed to the script : 3
The value of all command-line arguments : bmw ford toyota

Try the following examples:

ls /tmp
./math 10 + 2 
~/scripts/addzone cyberciti.com
~/scripts/adddomain cyberciti.biz '74.86.48.99' '2607:f0d0:1002:11::4' 
/etc/init.d/named reload
/usr/rc.d/jail restart cyberciti.biz
Shell script name ($0) Total number of arguments Actual Command line argument ($1,..,$9)