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ref: d3d1b3b47ff80f451c6c9f8b7f1262fef6545f2b
dir: /man/2/ether/

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.TH ETHER 2
.SH NAME
ether \- Ethernet address manipulation
.SH SYNOPSIS
.EX
include "ether.m";
ether := load Ether Ether->PATH;

Eaddrlen:	con 6;

init:   fn();
parse:  fn(s: string): array of byte;
text:   fn(a: array of byte): string;
addressof:  fn(dev: string): array of byte;
eqaddr: fn(a, b: array of byte): int;
.SH DESCRIPTION
.B Ether
provides a small set of functions that manipulate Ethernet MAC addresses,
for the use of the few applications such as
.IR bootpd (8)
that must work with them.
.PP
.B Init
must be called before using any other function in the module.
.PP
.B Parse
takes a textual representation of a MAC address in
.I s
and returns its internal representation as an array of bytes of length
.BR Eaddrlen ,
the form used in packets read and written via
.IR ether (3).
.I S
is a string of twelve hexadecimal digits, corresponding to the six bytes of a MAC address.
Each pair of digits can optionally be separated by a colon.
If
.I s
is invalid,
.B parse
returns nil.
.PP
.B Text
takes an array of bytes of length
.B Eaddrlen
and returns its textual representation (a string of twelve hexadecimal digits).
It returns
.LR <invalid>
if the array is less than
.BR Eaddrlen ,
but it ignores any bytes beyond that.
.PP
.B Addressof
returns the MAC address of the given Ether device
.I dev
(eg,
.LR /net/ether0 ),
which it reads from
.IB dev /addr .
It returns nil and sets the error string if that file does not exist or is invalid.
.PP
.B Eqaddr
returns true iff
.I a
and
.I b
are the same address.
.SH FILES
.TF /net/etherN/addr
.TP
.IB net /ether N /addr
hardware address of Ether
.I N
.SH SOURCE
.B /appl/lib/ether.b
.SH SEE ALSO
.IR ip (2),
.IR ether (3)