# To implement a for loop:
for file in *;
do 
    echo $file found;
done

# To implement a case command:
case "$1"
in
    0) echo "zero found";;
    1) echo "one found";;
    2) echo "two found";;
    3*) echo "something beginning with 3 found";;
esac

# Turn on debugging:
set -x

# Turn off debugging:
set +x