The Abuild.backing file may appear at the
root of a build forest. It specifies the locations of one or more
backing areas and, optionally, provides a list of build items a
trees that should not be inherited from the backing areas. For
details about backing areas, see Chapter 11, Backing Areas.
The syntax of the Abuild.backing file is
identical to that of the Abuild.conf file: it
contains a list of colon-separated key/value pairs. Blank lines
and lines beginning with the # character are
ignored.
The following keys are defined:
This key's value is a space-separated list of relative or
absolute paths to other build forests that are to be used as a
backing area to the current forest. It is the only required
key in the Abuild.backing file.
This key's value is a space-separated list of build items that should not be inherited from the backing area. Any build item listed here is treated as an unknown build item in the local forest.
This key's value is a space-separated list of build trees that should be inherited from the backing area. Any build item in any build tree listed here will not be made available from the backing area, and the build tree will not be considered a member of the local forest. Note that, unlike with deleted items, it is permissible to create a new build tree locally with the same name as a deleted tree. The new tree is not related to the old tree in any way, and the new tree will not inherit build items from an instance of the deleted tree in the backing areas.