Executing actions involves actually performing the install or remove methods specific to each action type on the image.
Execution begins with all the removal actions being executed. If any unexpected content is found in directories being removed from the system, that content is placed in /var/pkg/lost+found.
Execution then proceeds to install and update actions. Note that all the actions have been blended across all packages. Thus all the changes in a single package operation are applied to the system at once rather than package by package. This permits packages to depend on each other and exchange content safely. For details on how files are updated, see File Actions.