BSD 4_4 release

[unix-history] / usr / src / lib / libc / net / linkaddr.3

diff --git a/usr/src/lib/libc/net/linkaddr.3 b/usr/src/lib/libc/net/linkaddr.3
index 9248f57..54e3206 100644 (file)
--- a/usr/src/lib/libc/net/linkaddr.3
+++ b/usr/src/lib/libc/net/linkaddr.3
@@ -1,14 +1,40 @@
-.\" Copyright (c) 1993 The Regents of the University of California.
-.\" All rights reserved.
+.\" Copyright (c) 1993
+.\"    The Regents of the University of California.  All rights reserved.

 .\"
 .\" This code is derived from software contributed to Berkeley by
 .\" Donn Seeley at BSDI.
 .\"
 .\"
 .\" This code is derived from software contributed to Berkeley by
 .\" Donn Seeley at BSDI.
 .\"

-.\" %sccs.include.redist.man%
+.\" Redistribution and use in source and binary forms, with or without
+.\" modification, are permitted provided that the following conditions
+.\" are met:
+.\" 1. Redistributions of source code must retain the above copyright
+.\"    notice, this list of conditions and the following disclaimer.
+.\" 2. Redistributions in binary form must reproduce the above copyright
+.\"    notice, this list of conditions and the following disclaimer in the
+.\"    documentation and/or other materials provided with the distribution.
+.\" 3. All advertising materials mentioning features or use of this software
+.\"    must display the following acknowledgement:
+.\"    This product includes software developed by the University of
+.\"    California, Berkeley and its contributors.
+.\" 4. Neither the name of the University nor the names of its contributors
+.\"    may be used to endorse or promote products derived from this software
+.\"    without specific prior written permission.

 .\"
 .\"

-.\"     @(#)linkaddr.3 8.1 (Berkeley) %G%
+.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+.\" SUCH DAMAGE.

 .\"
 .\"

-.Dd 
+.\"     @(#)linkaddr.3 8.1 (Berkeley) 7/28/93
+.\"
+.Dd July 28, 1993

 .Dt LINK_ADDR 3
 .Os BSD 4.4
 .Sh NAME
 .Dt LINK_ADDR 3
 .Os BSD 4.4
 .Sh NAME


@@ -33,40 +59,40 @@ The routine
 .Fn link_ntoa
 takes
 a link-level
 .Fn link_ntoa
 takes
 a link-level

-addresses and returns
+address and returns an

 .Tn ASCII
 .Tn ASCII

-strings representing some of the information present
-(The link level address itself, and the interface name
-or number, if present.)
-This facility is still experimental, and had there been
-further development of the system would have been subject to change.
+string representing some of the information present,
+including the link level address itself, and the interface name
+or number, if present.
+This facility is experimental and is
+still subject to change.

 .Pp
 .Pp

-The syntax employed by
-.Fn link_addr
-is an optional network interface identifier (a string of the
-form
-.Dq name\ unit ,
+For
+.Fn link_addr ,
+the string
+.Fa addr
+may contain
+an optional network interface identifier of the form
+.Dq "name unit-number" ,

 suitable for the first argument to
 suitable for the first argument to

-.Xr ifconfig 4 )
-followed by a colon when the interface identifier is present,
-followed in all cases by a sequence of hexadecimal
-.Dq digits
-(optionally separated by periods),
-of the form:
-.Bd -filled -offset indent
-<name unit :> <hex digits>.<hex digits>.<hex digits>
-.Ed
+.Xr ifconfig 4 ,
+followed in all cases by a colon and
+an interface address in the form of
+groups of hexadecimal digits
+separated by periods.
+Each group represents a byte of address;
+address bytes are filled left to right from
+low order bytes through high order bytes.

 .Pp
 .Pp

-Each pair of hexadecimal digits represents a byte
-with the leading digit indicating the higher-ordered bits.
-A period following an even number of bytes has no
-effect (but may be used to increase legitibility).
-A period following an odd number of bytes has the
-effective of filling the byte of address being translated
-to have its higher order bits filled with zeros.
-.Pp
-Thus le0:8.0.9.13.d.30 represents an ethernet address
-to be transmitted on the first lance ethernet interface.
+.\" A regular expression may make this format clearer:
+.\" .Bd -literal -offset indent
+.\" ([a-z]+[0-9]+:)?[0-9a-f]+(\e.[0-9a-f]+)*
+.\" .Ed
+.\" .Pp
+Thus
+.Li le0:8.0.9.13.d.30
+represents an ethernet address
+to be transmitted on the first Lance ethernet interface.

 .Sh RETURN VALUES
 .Fn link_ntoa
 always returns a null terminated string.
 .Sh RETURN VALUES
 .Fn link_ntoa
 always returns a null terminated string.


@@ -86,7 +112,20 @@ functions appeared in
 .Sh BUGS
 The returned values for link_ntoa
 reside in a static memory area.
 .Sh BUGS
 The returned values for link_ntoa
 reside in a static memory area.

+.Pp

 The function
 .Fn link_addr
 should diagnose improperly formed input, and there should be an unambiguous
 way to recognize this.
 The function
 .Fn link_addr
 should diagnose improperly formed input, and there should be an unambiguous
 way to recognize this.

+.Pp
+If the
+.Va sdl_len
+field of the link socket address
+.Fa sdl
+is 0,
+.Fn link_ntoa
+will not insert a colon before the interface address bytes.
+If this translated address is given to
+.Fn link_addr
+without inserting an initial colon,
+the latter will not interpret it correctly.