Change all files and folders permissions of a directory to 644/755

Question

One approach could be using find:

for directories

find /desired_location -type d -print0 | xargs -0 chmod 0755

for files

find /desired_location -type f -print0 | xargs -0 chmod 0644

The easiest way is to do:

chmod -R u+rwX,go+rX,go-w /path/to/dir

which basically means:

to change file modes -Recursively by giving:

• user: read, write and eXecute permissions,
• group and other users: read and eXecute permissions, but not -write permission.

Please note that X will make a directory executable, but not a file, unless it's already searchable/executable.

+X - make a directory or file searchable/executable by everyone if it is already searchable/executable by anyone.

Please check man chmod for more details.

See also: How to chmod all directories except files (recursively)? at SU

The shortest one I could come up with is:

chmod -R a=r,u+w,a+X /foo

which works on GNU/Linux, and I believe on Posix in general (from my reading of: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/chmod.html).

What this does is:

1. Set file/directory to r__r__r__ (0444)
2. Add w for owner, to get rw_r__r__ (0644)
3. Set execute for all if a directory (0755 for dir, 0644 for file).

Importantly, the step 1 permission clears all execute bits, so step 3 only adds back execute bits for directories (never files). In addition, all three steps happen before a directory is recursed into (so this is not equivalent to e.g.

chmod -R a=r /foo
chmod -R u+w /foo
chmod -R a+X /foo

since the a=r removes x from directories, so then chmod can't recurse into them.)

On https://help.directadmin.com/item.php?id=589 they write:

If you need a quick way to reset your public_html data to 755 for directories and 644 for files, then you can use something like this:

cd /home/user/domains/domain.com/public_html
find . -type d -exec chmod 0755 {} \;
find . -type f -exec chmod 0644 {} \;

I tested and ... it works!