ethers(3N)                                                ethers(3N)


       NAME
             ethers - Ethernet address mapping operations

       SYNOPSIS
             cc [options] file -lsocket -lnsl
             #include <sys/types.h>
             #include <sys/socket.h>
             #include <net/if.h>
             #include <netinet/in.h>
             #include <netinet/if_ether.h>
             char *ether_ntoa(ether_addr_t e);
             ether_addr_t *ether_aton(char *s);
             int ether_ntohost(char *hostname, ether_addr_t e);
             int ether_hostton(char *hostname, ether_addr_t e);
             int ether_line(char *l, ether_addr_t e, char *hostname);

       DESCRIPTION
             These routines are useful for mapping 48-bit Ethernet numbers
             to their ASCII representations or their corresponding host
             names, and vice versa.

             The function ether_ntoa converts a 48-bit Ethernet number
             pointed to by e to its standard ASCII representation; it
             returns a pointer to the ASCII string.  The representation is
             of the form x:x:x:x:x:x where x is a hexadecimal number
             between 0 and ff.

             The function ether_aton converts an ASCII string in the
             standard representation back to a 48-bit Ethernet number;  the
             function returns NULL if the string cannot be scanned
             successfully.

             The function ether_ntohost maps an Ethernet number (pointed to
             by e) to its associated hostname.  The string pointed to by
             hostname must be long enough to hold the hostname and a NULL
             character.  The function returns 0 upon success and non-zero
             upon failure.

             Inversely, the function ether_hostton maps a hostname string
             to its corresponding Ethernet number; the function modifies
             the Ethernet number pointed to by e.  The function also
             returns 0 upon success and non-zero upon failure.

             The function ether_line scans a line (pointed to by l) and
             sets the hostname and the Ethernet number (pointed to by e).
             The string pointed to by hostname must be long enough to hold


                           Copyright 1994 Novell, Inc.               Page 1

      ethers(3N)                                                ethers(3N)


            the hostname and a NULL character.  The function returns 0
            upon success and non-zero upon failure.

            The format of the scanned line is described by ethers(4).

         Files
            /etc/ethers

      USAGE
            The return values from the ethers functions are pointers to
            static data, which will be overwritten on the next call.  For
            multi-threaded applications, this occurs on a per-thread
            basis.

      REFERENCES
            ethers(4)
































                          Copyright 1994 Novell, Inc.               Page 2