= Implement thread-safe versions of the getpwent(3) and getgrent(3)

= Implement thread-safe versions of the getpwent(3) and getgrent(3)
  family of functions using the new nsdispatch(3) core.  Remove
  arbitrary size limits when using the thread-safe versions.

= Re-implement the traditional getpwent(3)/getgrent(3) functions on
  top of the thread-safe versions.

= Update the on-disk format of the hashed version of the passwd(5)
  databases to allow for versioned entries.  The legacy version is
  `3'.  (Don't ask.)

= Add support for version `4' entries in the passwd(5) database.
  Entries in this format are identical to version 3 entries except
  that all integers are stored as 32-bit integers in network byte
  order (big endian).

= pwd_mkdb is updated to generate both version 3 and version 4
  entries.

Sponsored by:	DARPA, Network Associates Laboratories