ethers(3N)                       (TCP/IP)                        ethers(3N)


   NAME
         ethers - Ethernet address mapping operations

   SYNOPSIS
         #include <sys/types.h>
         #include <sys/socket.h>
         #include <net/if.h>
         #include <netinet/in.h>
         #include <netinet/if_ether.h>

              char *
              ether_ntoa(e)
                   struct ether_addr *e;

              struct ether_addr *
              ether_aton(s)
                   char *s;
              ether_ntohost(hostname, e)
                   char *hostname;
                   struct ether_addr *e;
              ether_hostton(hostname, e)
                   char *hostname;
                   struct ether_addr *e;
              ether_line(l, e, hostname)
                   char *l;
                   struct ether_addr *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 zero 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 zero 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


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   ethers(3N)                       (TCP/IP)                        ethers(3N)


         string pointed to by hostname must be long enough to hold the
         hostname and a NULL character.  The function returns zero upon
         success and non-zero upon failure.  The format of the scanned line is
         described by ethers(4).

   FILES
         /etc/ethers

   SEE ALSO
         ethers(4)











































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