Upgrade

admin upgrade

One command for the thing you will do most often, in an order worth not having to remember:

1. Refuse to start if admin diff reports drift. Upgrading a machine you cannot describe makes it harder to describe. admin save or admin apply first.
2. pacman -Syu. snap-pac takes a snapshot of / just before the transaction and another just after (see Snapshots).
3. admin apply, so that anything a package update reset comes back.
4. List any new .pacnew files.
5. Say whether a reboot is needed: when the running kernel’s modules are gone from /usr/lib/modules, the kernel was upgraded.

admin upgrade --yes passes --noconfirm to pacman and --yes to aconfmgr.

.pacnew files

When a package updates a configuration file you have changed, pacman keeps yours and writes its new version alongside as <file>.pacnew. That is how new options arrive on Arch – the Pi’s cmdline.txt is one – and pacman never merges them for you. admin upgrade lists them:

New .pacnew files (merge them, then 'admin save'):
  /etc/pacman.conf.pacnew

Compare the two, carry over what you want, and delete the .pacnew:

sudo vim -d /etc/pacman.conf /etc/pacman.conf.pacnew
sudo rm /etc/pacman.conf.pacnew
admin save

If the file is one the repo provides (under ~/arch/etc/), merge into the repo’s copy instead and admin apply. A .pacnew left lying around is drift too, so admin diff reports it until you deal with it.