Re: elle ne modifie pas les fichiers de configuration à l’insu de l’administrateur

man pacman

Handling Config Files
Pacman uses the same logic as rpm to determine action against files that are designated to be backed up. During an upgrade, 3 md5 hashes are used for each backup file to determine the required action: one for the original file installed, one for the new file that’s about to be installed, and one for the actual file existing on the filesystem. After comparing these 3 hashes, the follow scenarios can result:
original=X, current=X, new=X
All three files are the same, so overwrites are not an issue. Install the new file.
original=X, current=X, new=Y
The current file is the same as the original but the new one differs. Since the user did not ever modify the file, and the new one may contain improvements or bugfixes, install the new file.
original=X, current=Y, new=X
Both package versions contain the exact same file, but the one on the filesystem has been modified. Leave the current file in place.
original=X, current=Y, new=Y
The new file is identical to the current file. Install the new file.
original=X, current=Y, new=Z
All three files are different, so install the new file with a .pacnew extension and warn the user. The user must then manually merge any necessary changes into the original file.