Basic Bash Options/Argument Boilerplate.

getopts.sh

#!/usr/bin/env bash

function helper() { echo -e "\nOptions:\n\n\t-a <app>\n\t-v <version>\n"; exit; }

while getopts "a:v:h" opt; do
    case $opt in
    c) APP=$OPTARG; echo "APP: ${APP}";;
    v) VER=$OPTARG; echo "VER: ${VER}";;
    h|*) helper;;
    esac
done

# force user to pass all opts and args.
if [ "$#" -ne 4 ]; then
    helper;
fi