AbsSymlink returns an absolute path for the link from a file to a target.

FindFileSystem returns nil if a file system is installed.

IsTargetSymlink returns true if a target of a symlink is also a symlink.

ResolveUntilLastSymlink resolves until the last symlink.

build the root file system.

UrootPath returns the full path for a uroot file with the UROOT_ROOT environment variable taken into account.

Not all these paths may be populated or even exist but OTOH they might.