Hooks in Pacman

Pacman hooks is pacman's way of running pre and post tasks in the phase of package installation. It basically helps in automating things around package installation.

Applications

I personally use it to always maintain an up-to-date list of packages installed from the official repositories or from AUR — to always be ready for the scenario wherein I need to reinstall the system for any reason whatsoever.

Other potential applications of hooks commonly seen are to primarily automate the tasks around users and permissions management required before & after installation of certain packages. Additionally, hooks can be used to automate the cleanup process of the pacman cache directory /var/cache/pacman/pkg which stores all the package versions ever downloaded.

Conventions

Custom hooks should be present in the /etc/pacman.d/hooks directory and each hook file should have a .hook extension. The basic steps to write a hook can be understood here. Any scripts which is to be executed from the hooks should be placed inside the /etc/pacman.d/hooks.bin directory.

Summary

• These things are useful to know if we want to automate certain aspects around package installation in arch based distros
• We'd also use these hooks if we release a package for arch which:
  • needs the setup and registration of certain daemons with init systems like sytemd
  • needs custom permissions and user/usergroups configuration