#!/bin/bash
# Tear $1 into path to file (or directory) and path in file,
# if no such file exit with error.
after () { test -z "${2##*$1*}" && echo -n "${2#*$1}"; }
test "${1::1}" == "/" && path=$base || path="."
lastpath=$1
until test -z "$lastpath" || test -f "$path"
do
    path="$path/${lastpath%%/*}"
    lastpath=$(after / "$lastpath")
    test -e "$path" || exit 1
done
echo "$path $lastpath"