The ethers file contains information regarding the known (48 bit) Ethernet addresses of hosts on the Internet. For each host on an Ethernet, a single line should be present with the following information:
Ethernet address
official host name
Items are separated by any number of blanks and/or TAB characters. A `#' indicates the beginning of a comment extending to the end of line.
The standard form for Ethernet addresses is ``x:x:x:x:x:x'' where x is a hexadecimal number between 0 and ff, representing one byte. The address bytes are always in network order. Host names may contain any printable character other than a SPACE, TAB, NEWLINE, or comment character. It is intended that host names in the ethers file correspond to the host names in the hosts(5) file.
The ether_line() routine from the Ethernet address manipulation library, ethers(3N) may be used to scan lines of the ethers file.