How to chmod only directories

chmod.md

Use chmod +X (as opposed to +x) which will make only directories executable and leave files alone.

This is great for recursively fixing a Drupal files directory. For example:

chmod -R 664 sites/default/files && chmod -R a+X sites/default/files

That will make all your files writeable by you and the server, but not executable, but will also make directories executable (i.e., listable).

thank you very much sir

Thank you! I had used an ugly command

sudo find sites/default/files  -type d -exec chmod 774 {} \; &&  # for directories
sudo find sites/default/files  -type f -exec chmod 664 {} \;     # for files

before I saw your elegant solution.
But I made it more restrictive

sudo chmod -R 660 sites/default/files && sudo chmod -R ug+X sites/default/files