# 8.16 `nis` -- Interface to Sun's NIS (Yellow Pages)

Availability: UNIX.

The `nis` module gives a thin wrapper around the NIS library, useful for central administration of several hosts.

Because NIS exists only on Unix systems, this module is only available for Unix.

The `nis` module defines the following functions:

`match`(key, mapname)
  Return the match for key in map mapname, or raise an error (`nis.error`) if there is none. Both should be strings, key is 8-bit clean. Return value is an arbitrary array of bytes (i.e., may contain `NULL` and other joys).

  Note that mapname is first checked if it is an alias to another name.

`cat`(mapname)
  Return a dictionary mapping key to value such that `match(key, mapname)==value`. Note that both keys and values of the dictionary are arbitrary arrays of bytes.

  Note that mapname is first checked if it is an alias to another name.

`maps`()
  Return a list of all valid maps.

The `nis` module defines the following exception:

exception `error`
  An error raised when a NIS function returns an error code.