The mode of a Linux file is the numeric representation of it’s access rights.
The command to see the current mode of a file in Linux is:
~ stat --format '%a' settings.php 555
The opposite of that would be:
~ chmod 555 settings.php
Here is another more elaborate example of a .c file that was compiled under arm to substitute a 32-bit binary. This worked, but permissions had to be altered for warnings to go away.
root@arm64:/usr/bin# ls -lah procmail-wrapper* -rwxr-xr-x 1 root root 9.1K Jul 3 20:46 procmail-wrapper -rwsr-xr-x 1 root root 1.4M Jan 26 2022 procmail-wrapper.backup root@arm64:/usr/bin# stat --format '%a' procmail-wrapper.backup 4755 root@arm64:/usr/bin# stat --format '%a' procmail-wrapper 755 root@arm64:/usr/bin# chmod 4755 procmail-wrapper