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.\" $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