NAME    [Toc]    [Back]

     ether_aton,    ether_ntoa,    ether_addr,     ether_ntohost,
ether_hostton,
     ether_line - get ethers entry

SYNOPSIS    [Toc]    [Back]

     #include <netinet/if_ether.h>

     char *
     ether_ntoa(struct ether_addr *e);

     struct ether_addr *
     ether_aton(char *s);

     int
     ether_ntohost(char *hostname, struct ether_addr *e);

     int
     ether_hostton(char *hostname, struct ether_addr *e);

     int
     ether_line(char *l, struct ether_addr *e, char *hostname);

DESCRIPTION    [Toc]    [Back]

     Ethernet  addresses  are represented by the following structure:

           struct ether_addr {
                   u_int8_t  ether_addr_octet[6];
           };

     The ether_ntoa() function converts this  structure  into  an
ASCII string of
     the  form ``xx:xx:xx:xx:xx:xx'', consisting of 6 hexadecimal
numbers separated
 by colons.  It returns a pointer to  a  static  buffer
that is reused
     for each call.  The ether_aton() converts an ASCII string of
the same
     form and to a structure containing the 6 octets of  the  address.  It returns
  a  pointer  to  a static structure that is reused for
each call.

     The ether_ntohost() and ether_hostton()  functions  interrogate the
     database   mapping   host   names   to  Ethernet  addresses,
/etc/ethers.  The
     ether_ntohost() function looks up the given Ethernet address
and writes
     the  associated  host name into the character buffer passed.
This buffer
     should  be   MAXHOSTNAMELEN   characters   in   size.    The
ether_hostton() function
  looks up the given host name and writes the associated
Ethernet address
 into the structure passed.  Both functions return zero
if they find
     the requested host name or address, and -1 if not.

     Each call reads /etc/ethers from the beginning; if a `+' appears alone on
     a line in the file, then ether_hostton()  will  consult  the
ethers.byname
     YP  map,  and ether_ntohost() will consult the ethers.byaddr
YP map.

     The ether_line() function parses a line from the /etc/ethers
file and
     fills  in  the passed struct ether_addr and character buffer
with the Ethernet
 address and host name on the line.  It returns zero if
the line was
     successfully  parsed  and  -1  if not.  The character buffer
should be
     MAXHOSTNAMELEN characters in size.

FILES    [Toc]    [Back]

     /etc/ethers

SEE ALSO    [Toc]    [Back]

     ethers(5)

HISTORY    [Toc]    [Back]

     The     ether_ntoa(),     ether_aton(),     ether_ntohost(),
ether_hostton(), and
     ether_line()  functions were adopted from SunOS and appeared
in NetBSD
     0.9b.

BUGS    [Toc]    [Back]

     The data space used by these functions is static; if  future
use requires
     the data, it should be copied before any subsequent calls to
these functions
 overwrite it.

OpenBSD     3.6                        December     16,      1993