md5 all files in a directory tree

Question

I have a a directory with a structure like so:

.
├── Test.txt
├── Test1
│   ├── Test1.txt
│   ├── Test1_copy.txt
│   └── Test1a
│       ├── Test1a.txt
│       └─         


        

Answer 1

#!/bin/bash
shopt -s globstar
md5sum "$1"/** > "${1}__checksums.md5"

Explanation: shopt -s globstar(manual) enables ** recursive glob wildcard. It will mean that "$1"/** will expand to list of all the files recursively under the directory given as parameter $1. Then the script simply calls md5sum with this file list as parameter and > "${1}__checksums.md5" redirects the output to the file.