Template getopt bash util-linux

example_template_getopt.sh

#/bin/bash
set -ueo pipefail

usage() {
  cat <<EOF
Usage:  $0 [option] arg...
        $0 -h
				
Options: 
   -a, --aflag         set a flag
   -p, --par NUM       pass parameter par
   -h                  show this text and exit
   
Examples:
    $0 -a argument0
    $0 --par 0 argument0

Written by Kamil Cukrowski (c) 2017. Under MIT License.
EOF
}

# getopt
if [ $# -eq 0 ]; then usage; exit 1; fi
args=$(getopt --name "$0" -o ap:h -- "$@")
eval set -- "$args"
FLAGA=false PAR=0
while true; do
	case "${1/#-/}" in
		a) FLAGA=true; ;;
		p) PAR=$1; shift; ;;
		h) usage; exit 0; ;;
		-) shift; break; ;;
		*) echo "Error parsing argument: $1"; exit 1; ;;
	esac
	shift
done

echo "FLAGA=$FLAGA"
echo "PAR=$PAR"
echo "args: $@"