deb-triggers - Linux

Overview

deb-triggers is a command that manages package triggers, which are used to automate tasks during package installation and removal. It allows users to list, query, create, modify, and delete triggers for a specific package or all packages. This helps maintain system integrity and perform post-installation or pre-removal operations seamlessly.

Syntax

deb-triggers [commands] [options] [package]

Options/Flags

  • -a, –action=action: Set the trigger action. Valid actions are install, remove, upgrade, and all. Defaults to all.
  • -C, –count: Display the number of triggers for the specified package.
  • -c, –condition=condition: Set the trigger condition. Valid conditions are pre, post, and none. Defaults to pre.
  • -D, –delete: Delete the trigger specified by --id.
  • –get-trigger=id: Display the details of the trigger with the specified id.
  • -h, –help: Display help information.
  • -i, –id=id: Specify the trigger ID to modify or delete.
  • -l, –list: List all triggers.
  • -o, –output=format: Specify the output format. Valid formats are text and json. Defaults to text.

Examples

List all triggers:

deb-triggers -l

Create a trigger to run a script after nano installation:

deb-triggers --action install --condition post --package nano /bin/echo "Nano installed"

Delete a trigger with ID 5:

deb-triggers --delete --id 5

Display the details of the trigger with ID 2 in JSON format:

deb-triggers --get-trigger 2 --output json

Common Issues

  • Missing triggers: If triggers don’t seem to be working, check if the trigger package dpkg-dev is installed.
  • Trigger not executing: Ensure the trigger script has proper permissions and the path to the script is correct.

Integration

deb-triggers can be combined with other commands to automate complex tasks:

  • dpkg: Use deb-triggers to query or create triggers for packages managed by dpkg.
  • Shell scripting: Integrate deb-triggers into shell scripts to conditionally execute commands based on package actions.

Related Commands

  • apt-get: Manages package installation and removal.
  • dpkg: Manages Debian packages.
  • triggerd: Listens for package events and executes triggers.