up() {
if [ $# == 0 ]
then
cd ..
return
fi
if [ "${1//[^0-9]/}" != "$1" ]
then
echo "Not a number"
return
fi
STRING=""
for (( i=0; i<$1 ; i++ ))
do
STRING="$STRING../"
done
cd $STRING
}
up
is equivalent to cd .. and
up
N jumps up N directories
in the directory tree.