1.\" Copyright (c) 1996-1999 Whistle Communications, Inc. 2.\" All rights reserved. 3.\" 4.\" Subject to the following obligations and disclaimer of warranty, use and 5.\" redistribution of this software, in source or object code forms, with or 6.\" without modifications are expressly permitted by Whistle Communications; 7.\" provided, however, that: 8.\" 1. Any and all reproductions of the source or object code must include the 9.\" copyright notice above and the following disclaimer of warranties; and 10.\" 2. No rights are granted, in any manner or form, to use Whistle 11.\" Communications, Inc. trademarks, including the mark "WHISTLE 12.\" COMMUNICATIONS" on advertising, endorsements, or otherwise except as 13.\" such appears in the above copyright notice or in the software. 14.\" 15.\" THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 16.\" TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 17.\" REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 18.\" INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 19.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 20.\" WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 21.\" REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 22.\" SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 23.\" IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 24.\" RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 25.\" WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 26.\" PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 27.\" SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 28.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30.\" THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 31.\" OF SUCH DAMAGE. 32.\" 33.\" Author: Archie Cobbs <archie@FreeBSD.org> 34.\" 35.\" $FreeBSD$ 36.\" $Whistle: ng_tee.8,v 1.4 1999/01/25 23:46:27 archie Exp $ 37.\" 38.Dd January 19, 1999 39.Dt NG_TEE 4 40.Os 41.Sh NAME 42.Nm ng_tee 43.Nd netgraph ``tee'' node type 44.Sh SYNOPSIS 45.In netgraph/ng_tee.h 46.Sh DESCRIPTION 47The 48.Nm tee 49node type has a purpose similar to the 50.Xr tee 1 51command. 52.Nm Tee 53nodes are useful for debugging or 54.Dq snooping 55on a connection 56between two netgraph nodes. 57.Nm Tee 58nodes have four hooks, 59.Dv right , 60.Dv left , 61.Dv right2left , 62and 63.Dv left2right . 64All data received on 65.Dv right 66is sent unmodified to 67.Em both 68hooks 69.Dv left 70and 71.Dv right2left . 72Similarly, all data received on 73.Dv left 74is sent unmodified to both 75.Dv right 76and 77.Dv left2right . 78.Pp 79Packets may also be received on 80.Dv right2left 81and 82.Dv left2right ; 83if so, they are forwarded unchanged out hooks 84.Dv right 85and 86.Dv left , 87respectively. 88.Sh HOOKS 89This node type supports the following hooks: 90.Pp 91.Bl -tag -width foobarbarfoo 92.It Dv right 93The connection to the node on the right. 94.It Dv left 95The connection to the node on the left. 96.It Dv right2left 97Tap for right to left traffic. 98.It Dv left2right 99Tap for left to right traffic. 100.El 101.Sh CONTROL MESSAGES 102This node type supports the generic control messages, plus the following. 103.Bl -tag -width foo 104.It Dv NGM_TEE_GET_STATS 105Get statistics, returned as a 106.Dv "struct ng_tee_stats" . 107.It Dv NGM_TEE_CLR_STATS 108Clear statistics. 109.El 110.Sh SHUTDOWN 111This node shuts down upon receipt of a 112.Dv NGM_SHUTDOWN 113control message, or when all hooks have been disconnected. 114.Sh SEE ALSO 115.Xr tee 1 , 116.Xr netgraph 4 , 117.Xr ngctl 8 118.Sh HISTORY 119The 120.Nm 121node type was implemented in 122.Fx 4.0 . 123.Sh AUTHORS 124.An Julian Elischer Aq julian@FreeBSD.org 125