xref: /freebsd/usr.sbin/nghook/nghook.8 (revision 4b9d6057)
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32.\" $Whistle: nghook.8,v 1.4 1999/01/20 03:19:45 archie Exp $
33.\"
34.Dd October 24, 2003
35.Dt NGHOOK 8
36.Os
37.Sh NAME
38.Nm nghook
39.Nd connect to a
40.Xr netgraph 4
41node
42.Sh SYNOPSIS
43.Nm
44.Op Fl adlnSs
45.Op Fl m Ar msg
46.Ar path
47.Op Ar hookname
48.Nm
49.Fl e
50.Op Fl n
51.Op Fl m Ar msg
52.Ar path
53.Ar hookname
54.Ar program
55.Op Ar args ...
56.Sh DESCRIPTION
57The
58.Nm
59utility creates a
60.Xr ng_socket 4
61socket type node and connects it to hook
62.Ar hookname
63of the node found at
64.Ar path .
65If
66.Ar hookname
67is omitted,
68.Dq Li debug
69is assumed.
70.Pp
71If the
72.Fl e
73option is given, the third argument is interpreted as the path to a program,
74and this program is executed with the remaining arguments as its arguments.
75Before executing, the program Netgraph messages (specified by the
76.Fl m
77option) are sent to the node.
78The program is executed with its standard input (unless closed by
79.Fl n )
80and output connected to the hook.
81.Pp
82If the
83.Fl e
84option is not given, all data written to standard input is sent
85to the node, and all data received from the node is relayed
86to standard output.
87Messages specified with
88.Fl m
89are sent to the node before the loop is entered.
90The
91.Nm
92utility exits when
93.Dv EOF
94is detected on standard input in this case.
95.Pp
96The options are as follows:
97.Bl -tag -width indent
98.It Fl a
99Output each packet read in human-readable decoded
100.Tn ASCII
101form instead of raw binary.
102.It Fl d
103Increase the debugging verbosity level.
104.It Fl e
105Execute the program specified by the third argument.
106.It Fl l
107Loops all received data back to the hook in addition to writing it
108to standard output.
109.It Fl m Ar msg
110Before executing the program (in
111.Fl e
112mode) send the given ASCII control message to the node.
113This option may be given more than once.
114.It Fl n
115Do not attempt to read any data from standard input.
116The
117.Nm
118utility will continue reading from the node until stopped by a signal.
119.It Fl S
120Use file descriptor 0 for output instead of the default 1.
121.It Fl s
122Use file descriptor 1 for input instead of the default 0.
123.El
124.Sh SEE ALSO
125.Xr netgraph 3 ,
126.Xr netgraph 4 ,
127.Xr ngctl 8
128.Sh HISTORY
129The
130.Nm netgraph
131system was designed and first implemented at Whistle Communications, Inc.\&
132in a version of
133.Fx 2.2
134customized for the Whistle InterJet.
135.Sh AUTHORS
136.An Archie Cobbs Aq Mt archie@whistle.com
137.Sh BUGS
138Although all input is read in unbuffered mode,
139there is no way to control the packetization of the input.
140.Pp
141If the node sends a response to a message (specified by
142.Fl m ) ,
143this response is lost.
144