shell-script-template-optargs.sh

shell-script-template-optargs.sh

#!/usr/bin/env bash
set -o errexit
set -o pipefail

usage() {
echo "
    ${0##*/}
    DESCRIPTION:
        Script explanation

    USAGE:
        ${0##*/} [OPTION] ... [OPTION]

        -n (required)
            description
        -? -h
            display this help and exit
    EXAMPLE:
        ${0##*/} -n"
}

# check for empty argument
if [ -z "$1" ] ; then
    usage
    exit 1
fi

# check for options
while getopts "n:h-:" opt; do
    case ${opt} in
        n)
            variable="$OPTARG"
            ;;
        h)
            usage
            exit 2
            ;;
        \?) # invalid option
            echo Invalid option: -"$OPTARG"
            usage
            exit 3
            ;;
        :) # missing option
            echo Missing option argument for -"$OPTARG"
            usage
            exit 4
            ;;
        *) # unimplemented option
            usage
            exit 5
            ;;
    esac
done

# clear all options and reset the command line
shift $(( OPTIND -1 ))

# stores working directory
working_directory=$(pwd)
# stores script directory
script_directory=$(cd "$(dirname $0)"; pwd)

# changes to script directory
cd "$script_directory"

# check required arguments
if [ -z "$requirement" ] || [ -z "$requirement" ]; then
    usage
    exit 6
fi