Index for Section 3

Alphabetical listing for E

Bottom of page

ethers(3)
NAME
  ethers, ether_ntoa, ether_aton, ether_ntohost, ether_hostton, ether_line -
  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;

  Arguments

  The ether_addr structure is defined in <netinet/if_ether.h>

DESCRIPTION
  These routines are useful for mapping 48 bit Ethernet numbers to their
  ASCII representations or their corresponding host names, and vice versa.
  The mapping is obtained from the /etc/ethers database; see ethers(4).

  The function ether_ntoa() converts a 48 bit Ethernet number pointed to by e
  to its standard ACSII 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 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
      Database that maps Ethernet addresses to hostnames

RELATED INFORMATION
  Commands: rarpd(8)

  Files: packetfilter(7), ethers(4)

Index for Section 3

Alphabetical listing for E

Top of page