@Peter,

You’re absolutely right! Removing write permissions from a file (chmod a-w file) does not prevent it from being deleted if the user has write permission on the parent directory.

To truly prevent deletion, the best approach is:

1. Make the directory immutable, which will prevents any modifications, including file deletions inside the directory.

chattr +i directory/

2. Modify directory permissions.

chmod a-w directory/

This removes write access, preventing users from deleting files.

touch A
chmod a-w A
ls -l A

-r--r--r-- 1 psamuel psamuel 0 Feb 12 15:09 A

rm A
rm: remove write-protected regular empty file 'A'? y   # user types 'y' followed by NEWLINE
ls -l A
/bin/ls: cannot access 'A': No such file or directory