docs: def readlinkabs(l):
      """
      Return an absolute path for the destination 
      of a symlink
      """
      assert (os.path.islink(l))
      p = os.readlink(l)
      if os.path.isabs(p):
          return os.path.abspath(p)
      return os.path.abspath(os.path.join(os.path.dirname(l), p))