Direct and indirect maps can contain pointers to other direct, indirect, and built-in maps. This facility is beneficial when mixing local maps with NIS-managed maps. In such a situation, a local map, listed in the master map, contains a pointer to the NIS-managed maps.
A line of the form +mapname causes automount to consult the mentioned map as if it were included in the current map. If mapname is a relative pathname (not beginning with a slash), automount assumes it is an NIS map. If the pathname is an absolute pathname, automount looks for a local map of that name. For instance, you can have a few entries in your local auto.home map for the most commonly accessed home directories and follow them with the included NIS map:
tokyo -ro &:/home/& milan -ro &:/export/home +auto.homeAfter consulting the included map, automount continues scanning the current map so you can add more entries:
tokyo -ro &:/home/& milan -ro &:/export/home +auto.home -ro &:/home/&Finally, the map included can be a local file or even a built-in map. If the map name starts with a dash (-), automount consults the appropriate built-in map (see the ``Using built-in automount maps'' section in this chapter for more details on built-in maps).
+auto.home.finance # NIS map +auto.home.sales # NIS map +auto.home.engineering # NIS map +/etc/auto.mystuff # local map +auto.home # NIS map +-hosts # built-in hosts map &:/export/& # wild card