Filesystems – Recursively Change File Permissions but Not Directories

chmodfilesystemsfindpermissions

I was doing a mass recursive change of permissions of some files that I had migrated to a unix system. I changed them to ug+rw, but then I found that I could not traverse subdirectories. I looked at the man page for chmod and didn't see any explanation for excluding directories, so I googled a little and found that people used find to recursively change the permissions on directories to 'execute' for user and group. I did that and then I could look into them.

But it seemed to me that I should be able to be able to do this find chmod — to recursively change the files to read/write but not make the directories untraversable.
Have I done this the 'right' way or is there a simpler way to do it?

Best Answer

The better solution should be

chmod -R ug=rwX,o=rX /path

where the capital X means: set execute bit if

the file is a directory or already has execute permission for some user

(quoted from chmod man page).

Or also, if you want to use find

find /path \( -type f -exec chmod ug=rw,o=r   {} + \) -o \
           \( -type d -exec chmod ug=rwx,o=rx {} + \)

Related Solutions

Why can’t I change permission on a symlink on Mac

/Users/mego has an ACL that may be preventing access. That's what the + after the traditional unix permissions on the output of ls -l for this directory indicates. Run ls -lde /Users/mego to view this ACL.

Note that if a user is denied access to /Users/mego (what matters is the executable bit), it won't have access to anything under it. So if the web server user doesn't have execution permission /Users/mego, it doesn't matter that /Users/mego/opt/rel is world-readable: the web server user won't be able to reach that far. It doesn't matter that a symbolic link is involved, either: access through a symbolic link involves traversing the path to the target.

Use chmod to manipulate the ACL. The examples in the man page should get you going (if you can't figure out what you need from the examples, ask here, and post the output of ls -lde /Users/mego).

Shell Find – Locate Directories Without Subdirectories

You don't need to use awk at all. Use the built-in tests that ksh provides, something like this:

#!/bin/ksh

for NAME in *
do
    FOUND=no
    if [[ -d $NAME && $NAME != '.' && $NAME != '..' ]]
    then
        for SUBNAME in $NAME/*
        do
            if [[ -d $SUBNAME ]]
            then
                FOUND=yes
                break
            fi
        done
        if [[ $FOUND == no ]]
        then
            echo Found only files in $NAME
        fi
    fi
done

That little script looks in all the directories in the current directory, and tells you if they only contain files, no sub-directories.

Best Answer

Related Solutions

Why can’t I change permission on a symlink on Mac

Shell Find – Locate Directories Without Subdirectories

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