#!/bin/bash
OLDDIR=$PWD
DIR="$1"
SEP="$2"
EXC="$3"

[ ! "$DIR" ] && {
        DIR="."
}

[ ! "$SEP" ] && {
        SEP=" "
}

[ ! "$EXC" ] && {
        EXC=""
}

cd $DIR
COUNT=0

for foo in *
do
        MY_SEP=$SEP
        [ "$COUNT" = "0" ] && {
                MY_SEP=""
        }
        RES="$RES$MY_SEP$foo"
        COUNT=$(expr $COUNT + 1)
done

echo $RES
cd $OLDDIR