How to find duplicate filenames (recursively) in a given directory? BASH

Question

I need to find every duplicate filenames in a given dir tree. I dont know, what dir tree user will give as a script argument, so I dont know the directory hierarchy. I tried thi

Answer 1

This solution writes one temporary file to a temporary directory for every unique filename found. In the temporary file, I write the path where I first found the unique filename, so that I can output it later. So, I create a lot more files that other posted solutions. But, it was something I could understand.

Following is the script, named fndupe.

#!/bin/bash

# Create a temp directory to contain placeholder files.
tmp_dir=`mktemp -d`

# Get paths of files to test from standard input.
while read p; do
  fname=$(basename "$p")
  tmp_path=$tmp_dir/$fname
  if [[ -e $tmp_path ]]; then
    q=`cat "$tmp_path"`
    echo "duplicate: $p"
    echo "    first: $q"
  else
    echo $p > "$tmp_path" 
  fi
done

exit

Following is an example of using the script.

$ find . -name '*.tif' | fndupe

Following is example output when the script finds duplicate filenames.

duplicate: a/b/extra/gobble.tif
    first: a/b/gobble.tif

Tested with Bash version: GNU bash, version 4.1.2(1)-release (x86_64-redhat-linux-gnu)