The MountManager object is made available to a pile in order that child or sub-piles may be mounted to directories within the primary or parent pile. Here, we specify the public interface on this object. The MountManager object may be accessed through the special variable $mount_manager, which is global to the pile and must be used in order for the pile to be strictifiable.
mount (scalar, scalar, scalar)
This function mounts the sub-pile named in the first argument to the directory named in the third. The second argument is the physical location of the sub-pile in the directory structure.7.1
register (list ref)
This is used to list all the variables which should be shared between parent and sub-piles. All the variables listed will be aliased across the piles namespaces when control is passed to the sub-pile and de-aliased when control is returned to the parent.