VMS Help CC, Socket Routines, gethostbyaddr  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    Searches the host database sequentially from the beginning of
    the database for a host record with a given address.

    Syntax:

      #include  <netdb.h>

      struct hostent *gethostbyaddr(char *addr, int len, int type);