ethers(3N)             UNIX System V(Internet Utilities)             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/ifether.h>
      char *etherntoa(struct etheraddr *e);
      struct etheraddr *etheraton(char *s);
      int etherntohost(char *hostname, struct etheraddr *e);
      int etherhostton(char *hostname, struct etheraddr *e);
      int etherline(char *l, struct etheraddr *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 etherntoa 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 etheraton 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 etherntohost 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
      etherhostton 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 etherline 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 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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