Shell Programming and Scripting

CheckOptions()
{
        validOpts=$1
        shift
        while getopts $validOpts optLetter ; do
                echo $optLetter $OPTIND $OPTARG
        done
}

CheckOptions "abc" -a -b -d

if [[ $? -eq 0 ]] ; then
        echo OPTIND = $OPTIND
else
        echo OPTARG = $OPTARG
fi

while $etopts S:M: options
do
case ${PARAMETERS} in
                S)      SOMETHING=$OPTARG;;
                M)      MORE=$OPTARG;;
                *)      ERROR=1
        esac
done

if [[ ${M_ERR} -gt 0 ]]
then
echo $"error in what ru doing???"
exit 
fi
#you have to call your script like below 

checkoptions -Sabc -Ma

and in your script you have to define what the parameter S and M suppose to do ??