xref: /dragonfly/share/man/man4/ng_tee.4 (revision 984263bc)
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33.\" Author: Archie Cobbs <archie@FreeBSD.org>
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35.\" $FreeBSD: src/share/man/man4/ng_tee.4,v 1.12.2.1 2001/12/21 09:00:51 ru Exp $
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