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.\" Author: Archie Cobbs <archie@whistle.com>
.\"
.\" $FreeBSD$
.\" $Whistle: ng_tee.8,v 1.4 1999/01/25 23:46:27 archie Exp $
.\"
.Dd January 19, 1999
.Dt NG_TEE 8
.Os FreeBSD 4.0
.Sh NAME
.Nm ng_tee
.Nd netgraph ``tee'' node type
.Sh SYNOPSIS
.Fd #include <netgraph/ng_tee.h>
.Sh DESCRIPTION
The
.Nm tee
node type has a purpose similar to the
.Xr tee 1
command.
.Nm Tee
nodes are useful for debugging or ``snooping'' on a connection
between two netgraph nodes.
.Nm Tee
nodes have four hooks,
.Dv right ,
.Dv left ,
.Dv right2left ,
and
.Dv left2right .
All data received on
.Dv right
is sent unmodified to
.Em both
hooks
.Dv left
and
.Dv right2left .
Similarly, all data received on
.Dv left
is sent unmodified to both
.Dv right
and
.Dv left2right .
.Pp
Packets may also be received on
.Dv right2left
and
.Dv left2right ;
if so, they are forwarded unchanged out hooks
.Dv left
and
.Dv right ,
respectively.
.Sh HOOKS
This node type supports the following hooks:
.Pp
.Bl -tag -width foobarbarfoo
.It Dv right
The connection to the node on the right.
.It Dv left
The connection to the node on the left.
.It Dv right2left
Tap for right to left traffic.
.It Dv left2right
Tap for left to right traffic.
.El
.Sh CONTROL MESSAGES
This node type supports only the generic control messages.
.Sh SHUTDOWN
This node shuts down upon receipt of a
.Dv NGM_SHUTDOWN
control message, or when all hooks have been disconnected.
.Sh SEE ALSO
.Xr tee 1 ,
.Xr netgraph 4 ,
.Xr ngctl 8 .
.Sh AUTHOR
Julian Elischer <julian@whistle.com>