Shell script stem

my-script.sh

usage() {
    echo "my-script.sh [options]"
    echo ""
    echo "Options:"
    echo "    --simple-param, -s           : activate a feature"
    echo "    --complex-param, -c <value>  : set some value"
    echo "    --help, -h                   : print this help message"
}

while [ "$1" != "" ]; do
    case "$1" in
        -h | --help)
            usage
            exit
            ;;
        --simple-param|-s)
            some_feature=true
            ;;
        --complex-param|-c)
            shift
            some_data="$1"
            ;;
        *)
            echo "ERROR: unknown parameter \"$1\""
            usage
            exit 1
            ;;
    esac
    shift
done