I created this gist to demo this stackexchange answer: http://stackoverflow.com/questions/192249/how-do-i-parse-command-line-arguments-in-bash/14203146#14203146

equals_separated.sh

#!/bin/bash

for i in "$@"
do
case $i in
    -e=*|--extension=*)
    EXTENSION="${i#*=}"
    shift
    ;;
    -s=*|--searchpath=*)
    SEARCHPATH="${i#*=}"
    shift
    ;;
    -l=*|--lib=*)
    LIBPATH="${i#*=}"
    shift
    ;;
    --default)
    DEFAULT=YES
    shift
    ;;
    *)
            # unknown option
    ;;
esac
done
echo "FILE EXTENSION  = ${EXTENSION}"
echo "SEARCH PATH     = ${SEARCHPATH}"
echo "LIBRARY PATH    = ${LIBPATH}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
    echo "Last line of file specified as non-opt/last argument:"
    tail -1 $1
fi

space_separated.sh

#!/bin/bash
while [[ $# > 1 ]]
do
key="$1"
shift

case $key in
    -e|--extension)
    EXTENSION="$1"
    shift
    ;;
    -s|--searchpath)
    SEARCHPATH="$1"
    shift
    ;;
    -l|--lib)
    LIBPATH="$1"
    shift
    ;;
    --default)
    DEFAULT=YES
    shift
    ;;
    *)
            # unknown option
    ;;
esac
done
echo FILE EXTENSION  = "${EXTENSION}"
echo SEARCH PATH     = "${SEARCHPATH}"
echo LIBRARY PATH    = "${LIBPATH}"
echo "Number files in SEARCH PATH with EXTENSION:" $(ls -1 "${SEARCHPATH}"/*."${EXTENSION}" | wc -l)
if [[ -n $1 ]]; then
    echo "Last line of file specified as non-opt/last argument:"
    tail -1 $1
fi

test.sh

chmod +x space_separated.sh
chmod +x equals_separated.sh

echo Testing space_separated.sh
./space_separated.sh -e conf -s /etc -l /usr/lib /etc/hosts

echo Testing equals_separated.sh
./equals_separated.sh -e conf -s /etc -l /usr/lib /etc/hosts