A tool that based on the following:
$ sudo pacman -Syu [..] (1/3) upgrading pacman-mirrorlist warning: /etc/pacman.d/mirrorlist installed as /etc/pacman.d/mirrorlist.pacnew (2/3) upgrading shorewall warning: /etc/shorewall/zones installed as /etc/shorewall/zones.pacnew warning: /etc/shorewall/policy installed as /etc/shorewall/policy.pacnew warning: /etc/shorewall/interfaces installed as /etc/shorewall/interfaces.pacnew warning: /etc/shorewall/hosts installed as /etc/shorewall/hosts.pacnew warning: /etc/shorewall/rules installed as /etc/shorewall/rules.pacnew warning: /etc/shorewall/tunnels installed as /etc/shorewall/tunnels.pacnew (3/3) upgrading shorewall6 warning: /etc/shorewall6/zones installed as /etc/shorewall6/zones.pacnew warning: /etc/shorewall6/policy installed as /etc/shorewall6/policy.pacnew warning: /etc/shorewall6/interfaces installed as /etc/shorewall6/interfaces.pacnew warning: /etc/shorewall6/rules installed as /etc/shorewall6/rules.pacnew
It will (hopefully) do:
$ sudo pacmarge :: Updating pacmerge backup file archive... :: Attempting to merge changes to 11 file(s) [MERGED] /etc/pacman.d/mirrorlist [MERGED] /etc/shorewall/hosts [MERGED] /etc/shorewall/interfaces [MERGED] /etc/shorewall/policy [MERGED] /etc/shorewall/rules [MERGED] /etc/shorewall/tunnels [MERGED] /etc/shorewall/zones [MERGED] /etc/shorewall6/interfaces [MERGED] /etc/shorewall6/policy [MERGED] /etc/shorewall6/rules [MERGED] /etc/shorewall6/zones
But it might also corrupt all of those files and then proceed to eat a few kittens. You have been warned!