Chmod recursively

You can use chmod with the X mode letter (the capital X) to set the executable flag only for directories.

In the example below the executable flag is cleared and then set for all directories recursively:

~$ mkdir foo
~$ mkdir foo/bar
~$ mkdir foo/baz
~$ touch foo/x
~$ touch foo/y

~$ chmod -R go-X foo 
~$ ls -l foo
total 8
drwxrw-r-- 2 wq wq 4096 Nov 14 15:31 bar
drwxrw-r-- 2 wq wq 4096 Nov 14 15:31 baz
-rw-rw-r-- 1 wq wq    0 Nov 14 15:31 x
-rw-rw-r-- 1 wq wq    0 Nov 14 15:31 y

~$ chmod -R go+X foo 
~$ ls -l foo
total 8
drwxrwxr-x 2 wq wq 4096 Nov 14 15:31 bar
drwxrwxr-x 2 wq wq 4096 Nov 14 15:31 baz
-rw-rw-r-- 1 wq wq    0 Nov 14 15:31 x
-rw-rw-r-- 1 wq wq    0 Nov 14 15:31 y

A bit of explaination:

• chmod -x foo – clear the eXecutable flag for foo
• chmod +x foo – set the eXecutable flag for foo
• chmod go+x foo – same as above, but set the flag only for Group and Other users, don’t touch the User (owner) permission
• chmod go+X foo – same as above, but apply only to directories, don’t touch files
• chmod -R go+X foo – same as above, but do this Recursively for all subdirectories of foo