How to find all file extensions recursively from a directory?

问题

What command, or collection of commands, can I use to return all file extensions in a directory (including sub-directories)?

Right now, I'm using different combinations of ls and grep, but I can't find any scalable solution.

回答1:

How about this:

find . -type f -name '*.*' | sed 's|.*\.||' | sort -u

回答2:

find . -type f | sed 's|.*\.||' | sort -u

Also works on mac.

回答3:

list all extensions and their counts of current and all sub-directories

ls -1R | sed 's/[^\.]*//' | sed 's/.*\.//' | sort | uniq -c

回答4:

if you are using Bash 4+

shopt -s globstar
for file in **/*.*
do
  echo "${file##*.}
done

Ruby(1.9+)

ruby -e 'Dir["**/*.*"].each{|x|puts x.split(".")[-1]}' | sort -u

回答5:

Yet another solution using find (that should even sort file extensions with embedded newlines correctly):

# [^.]: exclude dotfiles
find . -type f -name "[^.]*.*" -exec bash -c '
  printf "%s\000" "${@##*.}"
' argv0 '{}' + |
sort -uz | 
tr '\0' '\n'

回答6:

Boooom another:

find * | awk -F . {'print $2'} | sort -u

回答7:

ls -1 | sed 's/.*\.//' | sort -u

Update: You are correct Matthew. Based on your comment, here is an updated version:

ls -R1 | egrep -C 0 "[^\.]+\.[^\./:]+$" | sed 's/.*\.//' | sort -u

回答8:

I was just quickly trying this as I was searching Google for a good answer. I am more Regex inclined than Bash, but this also works for subdirectories. I don't think includes files without extensions either:

ls -R | egrep '(\.\w+)$' -o | sort | uniq -c | sort -r

来源：https://stackoverflow.com/questions/4998290/how-to-find-all-file-extensions-recursively-from-a-directory