在Mac中仅通过root即可移动文件

Question

i'm trying to make a file removable just by root user In mac 10.10. i was try this :

chown root <fileName>

but other user can remove it;

any idea?

Answer 1

As an alternative to changing the permissions on the containing directory, you can set the uimmutable flag on the file:

sudo chown root foo
sudo chflags uimmutable foo

Now only root will be able to delete foo. Note, though, that nobody will be able to modify the file, either. Root could remove the uimmutable flag and then modify it, of course, but that opens a window for others to delete it.

Answer 2

The act of removing an entry in a directory modifies the directory, but not the file. (When you remove a file, you are unlinking the name from the file and the link count on the file is decremented. The file itself may not be deleted, but will no longer be accessible by the name that was removed.) In order to ensure that only some process with root privilege can unlink a file, you need to modify the permissions on the directory. So to ensure that no-one but root can delete the file /p/a/t/h/file:

sudo chown root /p/a/t/h  # make root the owner of the directory
sudo chmod og-w /p/a/t/h  # remove write permissions from other and group

Note that this is less fine grained that you might like and will prevent non-root users from removing or creating any files in /p/a/t/h .