Parse arguments in a bash script. Example.

read_arguments.sh

#!/bin/bash

#Are arguments given?
if [ $# -eq 0 ]; then
	#No... Exit.
	echo "Arguments required!"
	exit 1
fi

#Use getopts to parse arguments
# ...getopts "<Letters to check>" ...
# <Letters to check>:
#	Begin with ":" to avoid error output
#	Example: "ab:c" <- Check for Arguments -a and -c without extra parameter.
#			   and check for -b with additional parameter
while getopts ":ab:c" opt; do
	case $opt in
		a)
			echo "Option a!"
			;;
		b)
			echo "Option b! Parameter: $OPTARG"
			;;
		c)
			echo "Option c!"
			;;
		\?)
			#Triggered when found invalid argument
			echo "Invalid option: -$OPTARG"
			exit 1
			;;
		:)
			#Triggered when required parameter is missing
			#This example: Executed script with just -b
			echo "Option -$OPTARG requires an argument."
			exit 1
			;;
	esac
done