xref: /freebsd/share/man/man4/ng_tee.4 (revision 7f9d26bd9d1b2754da8429257edbde0a8237f84f)
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33.\" Author: Archie Cobbs <archie@whistle.com>
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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 8
40.Os FreeBSD 3
41.Sh NAME
42.Nm ng_tee
43.Nd netgraph ``tee'' node type
44.Sh SYNOPSIS
45.Fd #include <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 ``snooping'' on a connection
54between two netgraph nodes.
55.Nm Tee
56nodes have four hooks,
57.Dv right ,
58.Dv left ,
59.Dv right2left ,
60and
61.Dv left2right .
62All data received on
63.Dv right
64is sent unmodified to
65.Em both
66hooks
67.Dv left
68and
69.Dv right2left .
70Similarly, all data received on
71.Dv left
72is sent unmodified to both
73.Dv right
74and
75.Dv left2right .
76.Pp
77Packets may also be received on
78.Dv right2left
79and
80.Dv left2right ;
81if so, they are forwarded unchanged out hooks
82.Dv left
83and
84.Dv right ,
85respectively.
86.Sh HOOKS
87This node type supports the following hooks:
88.Pp
89.Bl -tag -width foobarbarfoo
90.It Dv right
91The connection to the node on the right.
92.It Dv left
93The connection to the node on the left.
94.It Dv right2left
95Tap for right to left traffic.
96.It Dv left2right
97Tap for left to right traffic.
98.El
99.Sh CONTROL MESSAGES
100This node type supports only the generic control messages.
101.Sh SHUTDOWN
102This node shuts down upon receipt of a
103.Dv NGM_SHUTDOWN
104control message, or when all hooks have been disconnected.
105.Sh SEE ALSO
106.Xr tee 1 ,
107.Xr netgraph 4 ,
108.Xr ngctl 8 .
109.Sh AUTHOR
110Julian Elischer <julian@whistle.com>
111