Most often, when you search something extremly simple and obvious, you have a hard time finding it. The simpler and the more obvious, the harder. This time I wanted to send a listing of a directory structure per email, no complex content, no HTML no Doc (how again do you export directory-trees directly into a graphic or document?).

Here is the result (public domain):

#!/bin/bash

target=.
prefix=
last=

if test $# -gt 0; then
  target="$1"
fi
if test $# -gt 1; then
  prefix="$2"
fi

############################################################
# to make files-first-dirs-last:
# - scan files first seperatly
# - scan directories after seperatly

############################################################
# determine which is the last entry
# can either be a file or a directory
for sub in "$target"/*; do
   if test -f "$sub"; then
      num=$(ls -1 "$sub" | wc -l)
      if [ $num -gt 0 ]; then
         last=”$sub”
      fi
   fi
done

for sub in “$target”/*; do
   if test -d “$sub”; then
      num=$(ls -1 “$sub” | wc -l)
      if [ $num -gt 0 ]; then
         last=”$sub”
      fi
   fi
done

############################################################
# print the files available in the given directory
# then determine if there are parent-directories
# that also contain files, which we enter only if yes
for sub in “$target”/*; do
   if test -f “$sub”; then
      if [ "$last" != "$sub" ]; then
         echo “$prefix” \+- ${sub#$target\/}
      fi
      if [ "$last" = "$sub" ]; then
         echo “$prefix” \`- ${sub#$target\/}
      fi
   fi
done

for sub in “$target”/*; do
   if test -d “$sub”; then
      num=$(ls -1 “$sub” | wc -l)
      if [ $num -gt 0 ]; then
         echo “$prefix” \|

         if [ "$last" != "$sub" ]; then
            echo “$prefix” \+- ${sub#$target\/}
            echo “$prefix” \|\ \ \|
            treef “$sub” “$prefix | ”
         fi
         if [ "$last" = "$sub" ]; then
            echo “$prefix” \`- ${sub#$target\/}
            echo “$prefix” \ \ \ \|
            treef “$sub” “$prefix   ”
         fi
      fi
   fi
done

If you got faster variatoins of this quick hack fitting my needs, I’m going to update the code with your suggestions. Here BTW is an example of the output:

$ treef Windows\ NT
 +- htrn_jis.dll
 +- hypertrm.exe
 |
 +- Accessories
 |  |
 |  +- mswrd6.wpc
 |  +- mswrd8.wpc
 |  +- wordpad.exe
 |  `- write.wpc
 |
 `- Pinball
    |
    `- New Textdokument.txt