On Linux you can make files unalterable to anyone – including system processes. In particulary this helps me when my system keeps deleting my getmail program (which isn’t from a repo) with every system update.

Make files immutable

Make it immutable, so it cannot be changed or removed (preserving the fix I’ve made for the mistyping in mime subclasses)

sudo chattr -V +i /usr/local/bin/getmail

This makes it immutable.

Check which attribute flags are at work on files

See what attribute flags (like “immutable”) attributes:

lsattr