[src/trunk]: src/share/man/man4 document scoped address issues.

[itojun <itojun%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/2c3c31818b82
branches:  trunk
changeset: 474297:2c3c31818b82
user:      itojun <itojun%NetBSD.org@localhost>
date:      Sat Jul 03 05:19:45 1999 +0000

description:
document scoped address issues.

diffstat:

 share/man/man4/inet6.4 |  36 +++++++++++++++++++++++++++++++++++-
 1 files changed, 35 insertions(+), 1 deletions(-)

diffs (53 lines):

diff -r 4b95b98ae5ef -r 2c3c31818b82 share/man/man4/inet6.4
--- a/share/man/man4/inet6.4    Sat Jul 03 04:45:53 1999 +0000
+++ b/share/man/man4/inet6.4    Sat Jul 03 05:19:45 1999 +0000
@@ -25,7 +25,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"    $Id: inet6.4,v 1.2 1999/07/01 10:50:48 itojun Exp $
+.\"    $Id: inet6.4,v 1.3 1999/07/03 05:19:45 itojun Exp $
 .\"
 .Dd January 29, 1999
 .Dt INET6 4
@@ -107,6 +107,40 @@
 .Dv sin6_addr
 field into 0, or by using the address contained in variable
 .Dv in6addr_any .
+.Pp
+IPv6 defines scoped address such as link-local or site-local address.
+To manipulate link-local addresses properly from the userland,
+programs must use advanced API defined in RFC2292.
+Otherwise, the address is ambiguous to the kernel and error will be generated.
+Scoped address is not for daily use at this moment both from specification
+and implementation point of view.
+Most of normal userland program
+like
+.Xr telnet 1
+or
+.Xr telnetd 8
+cannot handle scoped address properly.
+Only special programs,
+like
+.Xr ping6 8 ,
+supports scoped address.
+For example,
+.Xr ping6 8
+has special option for specifying outgoing interface
+to disambiguate scoped addresses.
+.Pp
+Scoped addresses are handled specially in the kernel.
+Scoped addresses will have its interface index embedded into the address,
+in routing table or interface structure.
+Therefore,
+the address on some of the kernel structure is not the same as that on the wire.
+The embedded index will be visible on
+.Dv PF_ROUTE
+socket and results from
+.Xr ifconfig 8 ,
+HOWEVER, users should never use the embedded form.
+For details please consult
+.Pa sys/netinet6/IMPLEMENTATION .
 .Sh PROTOCOLS
 The
 .Nm