ETHER_ATON(3)		   Linux Programmers Manual		ETHER_ATON(3)



NAME
       ether_aton,   ether_ntoa,   ether_ntohost,  ether_hostton,  ether_line,
       ether_ntoa_r, ether_aton_r - Ethernet address manipulation routines

SYNOPSIS
       #include 

       char *ether_ntoa(const struct ether_addr *addr);

       struct ether_addr *ether_aton(const char *asc);

       int ether_ntohost(char *hostname, const struct ether_addr *addr);

       int ether_hostton(const char *hostname, struct ether_addr *addr);

       int ether_line(const char *line, struct ether_addr *addr,
		      char *hostname);

       /* GNU extensions */
       char *ether_ntoa_r(const struct ether_addr *addr, char *buf);

       struct ether_addr *ether_aton_r(const char *asc,
				       struct ether_addr *addr);

DESCRIPTION
       ether_aton() converts the 48-bit Ethernet host  address	asc  from  the
       standard  hex-digits-and-colons	notation  into	binary data in network
       byte order and returns a  pointer  to  it  in  a  statically  allocated
       buffer,	which  subsequent  calls will overwrite.  ether_aton() returns
       NULL if the address is invalid.

       The ether_ntoa() function converts the Ethernet host address addr given
       in  network  byte  order  to a string in standard hex-digits-and-colons
       notation, omitting leading zeros.  The string is returned in  a	stati
       cally allocated buffer, which subsequent calls will overwrite.

       The  ether_ntohost()  function  maps  an Ethernet address to the corre
       sponding hostname in /etc/ethers and returns non-zero if it  cannot  be
       found.

       The  ether_hostton() function maps a hostname to the corresponding Eth
       ernet address in /etc/ethers and  returns  non-zero  if	it  cannot  be
       found.

       The ether_line() function parses a line in /etc/ethers format (ethernet
       address followed by whitespace followed by hostname; '#'  introduces  a
       comment)  and  returns  an address and hostname pair, or non-zero if it
       cannot be parsed.  The buffer pointed to by  hostname  must  be	suffi
       ciently long, for example, have the same length as line.

       The  functions  ether_ntoa_r() and ether_aton_r() are reentrant thread-
       safe versions of ether_ntoa() and ether_aton() respectively, and do not
       use static buffers.

       The structure ether_addr is defined in  as:

	   struct ether_addr {
	       uint8_t ether_addr_octet[6];
	   }

CONFORMING TO
       4.3BSD, SunOS.

BUGS
       The glibc 2.2.5 implementation of ether_line() is broken.

SEE ALSO
       ethers(5)

COLOPHON
       This  page  is  part of release 3.05 of the Linux man-pages project.  A
       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.



GNU				  2002-07-20			 ETHER_ATON(3)