Use GNU find to show only the leaf directories

BashShellFindGnu

Bash Problem Overview


I'm trying to use GNU find to find only the directories that contain no other directories, but may or may not contain regular files.

My best guess so far has been:

find dir -type d \( -not -exec ls -dA ';' \)

but this just gets me a long list of "."

Thanks!

Bash Solutions


Solution 1 - Bash

You can use -links if your filesystem is POSIX compliant (ie, a directory has a link for each subdirectory in it, a link from its parent and a link to self, thus a count of 2 link if it has no subdirectories).

The following command should do what you want:

find dir -type d -links 2

However, it does not seems to work on Mac OS X (as @Piotr mentionned). Here is another version that is slower, but does work on Mac OS X. It is based on his version, with correction to handle whitespace in directory names:

find . -type d -exec sh -c '(ls -p "{}"|grep />/dev/null)||echo "{}"' \;

Solution 2 - Bash

I just found another solution to this that works on both Linux & macOS (without find -exec)!

It involves sort (twice) and awk:

find dir -type d | sort -r | awk 'a!~"^"$0{a=$0;print}' | sort
Explanation:
  1. sort the find output in reverse order
  • now you have subdirectories appear first, then their parents
  1. use awk to omit lines if the current line is a prefix of the previous line
  • (this command is from the answer here)
  • now you eliminated "all parent directories" (you're left with parent dirs)
  1. sort them (so it looks like the normal find output)
  2. Voila! Fast and portable.

Solution 3 - Bash

@Sylvian solution didn't work for me on mac os x for some obscure reason. So I've came up with a bit more direct solution. Hope this will help someone:

find . -type d  -print0 | xargs -0 -IXXX sh -c '(ls -p XXX | grep / >/dev/null) || echo XXX' ;

Explanation:

  • ls -p ends directories with '/'
  • so (ls -p XXX | grep / >/dev/null) returns 0 if there is no directories
  • -print0 && -0 is to make xargs handle spaces in directory names

Solution 4 - Bash

I have some oddly named files in my directory trees that confuse awk as in @AhmetAlpBalkan 's answer. So I took a slightly different approach

  p=;
  while read c;
    do 
      l=${#c};
      f=${p:0:$l};
      if [ "$f" != "$c" ]; then 
        echo $c; 
      fi;
      p=$c; 
    done < <(find . -type d | sort -r) 

As in the awk solution, I reverse sort. That way if the directory path is a subpath of the previous hit, you can easily discern this.

Here p is my previous match, c is the current match, l is the length of the current match, f is the first l matching characters of the previous match. I only echo those hits that don't match the beginning of the previous match.

The problem with the awk solution offered is that the matching of the beginning of the string seems to be confused if the path name contains things such as + in the name of some of the subdirectories. This caused awk to return a number of false positives for me.

Solution 5 - Bash

This awk/sort pipe works a bit better than the one originally proposed in this answer, but is heavily based on it :) It will work more reliably regardless of whether the path contains regex special characters or not:

find . -type d | sort -r | awk 'index(a,$0)!=1{a=$0;print}' | sort

Remember that awk strings are 1-indexed instead of 0-indexed, which might be strange if you're used to working with C-based languages.

If the index of the current line in the previous line is 1 (i.e. it starts with it) then we skip it, which works just like the match of "^"$0.

Solution 6 - Bash

What about this one ? It's portable and it doesn't depend on finnicky linking counts. Note however that it's important to put root/folder without the trailing /.

find root/folder -type d | awk '{ if (length($0)<length(prev) || substr($0,1,length(prev))!=prev) print prev; prev=($0 "/") } END { print prev }'

Solution 7 - Bash

Here is solution which works on Linux and OS X:

find . -type d -execdir bash -c '[ "$(find {} -mindepth 1 -type d)" ] || echo $PWD/{}' \; 

or:

find . -type d -execdir sh -c 'test -z "$(find "{}" -mindepth 1 -type d)" && echo $PWD/{}' \;

Solution 8 - Bash

My 2 cents on this problem:

(
for listed_file in $(find . -type f)
do
    listed_file_name=$(basename "$listed_file")
    listed_directory=${listed_file/$listed_file_name/}
    echo "$listed_directory"
done
) | sort | uniq

It uses a subshell to capture output from the run, and shell parameter expansion to get each directory name, then sort and filter unique values. Searching only for files ensure that no intermediate directories will be listed for each file.

Attributions

All content for this solution is sourced from the original question on Stackoverflow.

The content on this page is licensed under the Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license.

Content TypeOriginal AuthorOriginal Content on Stackoverflow
QuestionThomas G HenryView Question on Stackoverflow
Solution 1 - BashSylvain DefresneView Answer on Stackoverflow
Solution 2 - Bashahmet alp balkanView Answer on Stackoverflow
Solution 3 - BashPiotr CzaplaView Answer on Stackoverflow
Solution 4 - BashA.EllettView Answer on Stackoverflow
Solution 5 - BashDaniel GrayView Answer on Stackoverflow
Solution 6 - BashDREVView Answer on Stackoverflow
Solution 7 - BashkenorbView Answer on Stackoverflow
Solution 8 - BashNiloctView Answer on Stackoverflow