10-21-2021, 12:47 AM
What do you mean by junk files and what kind of failure do you mean? I don't think pacman writes any temporary files that keep lingering on the system somewhere. It does however cache downloaded packages (in /var/chache/pacman/pkg/), but for a reason. Check out the Arch wiki for more details and instructions on how to clean the cache. After a failed update, just try updating again. It might be another problem if the update was interrupted by external causes like power loss.

How to find and remove junk files from failed updates?
