How to merge two directories in Ubuntu 16.04?

Question

I have two folders /var/first/app and /var/second/app. I have different files within both folders and few are same. I want to merge /var/second/app to /var/first/app. How can I do that?

Answer 1

This should do the trick:

rsync -av /var/second/app /var/first/app

Answer 2

Use something like:

cp -r /var/first/app /var/second/
rm -r /var/first/app

or change cp -r to cp -a to preserve ownership and timestamps.

You can also use -i to make sure what is going on. it's going to prompt you before overwriting anything.

Answer 3

You may first backup your destination folder (just in case) :

cp -r /var/first/app /var/first/app.backup

If you don't care overwriting files :

cp -fr /var/second/app /var/first/app

It will copy recursively the second folder into the first one, overwriting files with same names.

If you don't want to overwrite existing files :

cp -nr /var/second/app /var/first/app

If all is ok, you can remove the backup :

rm -rf /var/first/app.backup