while [ -n "$1" ]; do
        case $1 in
                -username)       if [ "`echo $2 | grep -e '^-[a-z]'`" ]; then { echo "missing value for '$1' (seen '$2')"; usage; exit 1; } else { shift; USERNAME=$1;   } fi ;;
                -surname)    if [ "`echo $2 | grep -e '^-[a-z]'`" ]; then { echo "missing value for '$1' (seen '$2')"; usage; exit 1; } else { shift; SURNAME=$1;     } fi ;;
                -address)    if [ "`echo $2 | grep -e '^-[a-z]'`" ]; then { ADDRESS=NO; }    else { shift; ADDRESS=$1;     } fi ;;
                -startdate)  if [ "`echo $2 | grep -e '^-[a-z]'`" ]; then { STARTDATE=NO; UNTIL=NO;}   else { shift; STARTDATE=$1; UNTIL=$1;  } fi ;;
                -req)        if [ "`echo $2 | grep -e '^-[a-z]'`" ]; then { REQ=Y; }    else { shift; REQ=$1;    } fi ;;
                -opt)
                        if [ -n "$2" ]; then
                                shift; OPT=$*
                                break
                        else
                                OPT=NOTSET
                        fi
                        ;;
                *)             echo "Invalid argument '$1'"; exit 1;;
        esac
        shift
done

shift; OPT=$*