#!/bin/bash
for OPT in "$@"
do
    echo "OPT: $OPT"
    case "$OPT" in
            '-p' | '--password' )
                    if [[ -z "$2" ]] || [[ "$2" =~ ^-+ ]]
                    then
                            echo "$PROGNAME: option requires an argument -- '$(echo $1 | sed 's/^-*//')'"
                            exit 2
                    fi
                    PASSWORD="$2"
                    shift 2
                    ;;
            '-u' | '--user' )
                    if [[ -z "$2" ]] || [[ "$2" =~ ^-+ ]]
                    then
                            echo "$PROGNAME: option requires an argument -- '$(echo $1 | sed 's/^-*//')'"
                            exit 2
                    fi
                    USER="$2"
                    shift 2
                    ;;
            * )
                    echo "$1"
                    echo "$PROGNAME: illigal option or argument -- '$(echo $1 | sed 's/^-*//')'"
                    exit 1
                    ;;
    esac
done
echo "GOOD"

#./command
GOOD

#./command -u user
OPT: -u
OPT: user

adduserall: illigal option or argument -- ''

#./command -u user -p passwd
OPT: -u
OPT: user
-p
adduserall: illigal option or argument -- 'p'