Write a shell program to do a depth-first traversal of a directory tree.

#!/bin/sh

doindent()
{
# Do a small indent depending on how deep into the tree we are
# Depending on your environment, you may need to use
# echo " \c" instead of
# echo -en " "
j=0;
while [ "$j" -lt "$1" ]; do
echo -en " "
j=`expr $j + 1`
done
}


traverse()
{
# Traverse a directory
indent="$2"

ls "$1" | while read i
do
doindent $2
if [ -d "$1/$i" ]; then
echo "Directory: $1/$i"
# Calling this as a subshell means that when the called
# function changes directory, it will not affect our
# current working directory
traverse "$1/$i" `expr $2 + 1`
else
echo "File: $1/$i"
fi
done
}

if [ -z "$1" ]; then
traverse . 0
else
traverse "$1" 0
fi