`apparmor.d` supports build directives, they are processed at build time of the project. They are valid AppArmor comments, therefore, `apparmor_parser` can be used on a profile even if the directives have not been processed. They should not end with a comma. Multiline directive is not supported.
The `only` and `exclude` directives can be used to filter individual rule or rule paragraphs depending on the target distribution or distribution family.
The `exec` directive is useful to allow executing transitions to a profile without having to manage the possible long list of profile attachments (it varies depending on the distribution). The directive parses and resolves the attachment variable (`@{exec_path}`) of the target profile and includes it in the current profile.
[Stacked](https://gitlab.com/apparmor/apparmor/-/wikis/AppArmorStacking) profiles can be hard to maintain. The *parent* profile needs to manage its own rules as well as always including access from the *child* profile. In most profile using stacking, the *child* profile is often naturally included in the *parent*. However, sometime the child profile is fully different. This directive automatically include the stacked profile rules into the parent profile.
: If `X` is set, the directive will conserve the `x` file rules regardless of the transition. It is not enabled by default as it may conflict with the parent profile. Indeed, automatically adding `Px` and `ix` transition in a profile is a very effective way to have conflict between transitions as you can automatically add rule already present in the profile but with another transition (you would then get the AppArmor error: `profile has merged rule with conflicting x modifiers`).
