ETHERS(3) | Library Functions Manual | ETHERS(3) |
ether_ntoa
, ether_aton
,
ether_ntohost
, ether_hostton
,
ether_line
—
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <net/if_ether.h>
char *
ether_ntoa
(const
struct ether_addr *e);
struct ether_addr *
ether_aton
(const
char *s);
int
ether_ntohost
(char
*hostname, const struct
ether_addr *e);
int
ether_hostton
(const
char *hostname, struct
ether_addr *e);
int
ether_line
(const
char *line, struct
ether_addr *e, char
*hostname);
struct ether_addr { u_char 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 data base
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. 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 hostname buffer for
ether_line
() and
ether_ntohost
() should be at least
MAXHOSTNAMELEN
+ 1 characters long, to prevent a
buffer overflow during parsing.
ether_ntoa
(), ether_aton
(),
ether_ntohost
(),
ether_hostton
(), and
ether_line
() functions were adopted from SunOS and
appeared in NetBSD 1.0.
November 2, 1997 | NetBSD 9.0 |