A simple script for finding and dealing with .pacnew files produced during Arch Linux system upgrades.

As an Arch Linux novice, I was not aware of the importance of .pacnew files. During a recent upgrade, I failed to notice the warning message (buried in hundreds of lines of output) telling me that my /etc/pam.d/system-login file was changed and needed to be manually updated. After a reboot, I found myself unable to login to my own system. Although the solution turned out to be straightforward (boot with kernel command line init=/bin/bash and edit the file), the moment of panic was real.

So I started reading about .pacnew files and ways to manage them automatically. pacdiff seemed great at first, but I'm not a huge fan of vimdiff or merge tools in general. I tried a couple others as well, but none of them felt quite right. So I made pacnoob.

Download the script, make it executable, and copy it to /usr/local/bin/:

$ curl https://raw.githubusercontent.com/jwgcarlson/pacnoob/master/pacnoob -o pacnoob
$ chmod +x pacnoob
$ sudo cp pacnoob /usr/local/bin/

To run it automatically after a system upgrade (so that you never forget), add a Pacman hook:

$ sudo mkdir -p /etc/pacman.d/hooks/
$ sudo tee -a /etc/pacman.d/hooks/pacnoob.hook >/dev/null << EOF
[Trigger]
Operation = Upgrade
Type = Package
Target = *

[Action]
Description = Running pacnoob
When = PostTransaction
Exec = /usr/local/bin/pacnoob
EOF

Ultimately I'd like to have something like git add --patch, which is a fantastic tool for selectively applying a subset of a diff. I couldn't find a good way to use it outside of a git context though, so I settled for a cheap knock-off.