1.\" Copyright (c) 1985, 1991 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)inetd.8 6.7 (Berkeley) 3/16/91 33.\" 34.Dd March 16, 1991 35.Dt INETD 8 36.Os BSD 4.3 37.Sh NAME 38.Nm inetd 39.Nd internet 40.Dq super-server 41.Sh SYNOPSIS 42.Nm inetd 43.Op Fl d 44.Op Ar configuration file 45.Sh DESCRIPTION 46.Nm Inetd 47should be run at boot time by 48.Pa /etc/rc.local 49(see 50.Xr rc 8 ) . 51It then listens for connections on certain 52internet sockets. When a connection is found on one 53of its sockets, it decides what service the socket 54corresponds to, and invokes a program to service the request. 55After the program is 56finished, it continues to listen on the socket (except in some cases which 57will be described below). Essentially, 58.Nm inetd 59allows running one daemon to invoke several others, 60reducing load on the system. 61.Pp 62The option available for 63.Nm inetd: 64.Bl -tag -width Ds 65.It Fl d 66Turns on debugging. 67.El 68.Pp 69Upon execution, 70.Nm inetd 71reads its configuration information from a configuration 72file which, by default, is 73.Pa /etc/inetd.conf . 74There must be an entry for each field of the configuration 75file, with entries for each field separated by a tab or 76a space. Comments are denoted by a ``#'' at the beginning 77of a line. There must be an entry for each field. The 78fields of the configuration file are as follows: 79.Pp 80.Bd -unfilled -offset indent -compact 81service name 82socket type 83protocol 84wait/nowait 85user 86server program 87server program arguments 88.Ed 89.Pp 90The 91.Em service-name 92entry is the name of a valid service in 93the file 94.Pa /etc/services . 95For 96.Dq internal 97services (discussed below), the service 98name 99.Em must 100be the official name of the service (that is, the first entry in 101.Pa /etc/services ) . 102.Pp 103The 104.Em socket-type 105should be one of 106.Dq stream , 107.Dq dgram , 108.Dq raw , 109.Dq rdm , 110or 111.Dq seqpacket , 112depending on whether the socket is a stream, datagram, raw, 113reliably delivered message, or sequenced packet socket. 114.Pp 115The 116.Em protocol 117must be a valid protocol as given in 118.Pa /etc/protocols . 119Examples might be 120.Dq tcp 121or 122.Dq udp . 123.Pp 124The 125.Em wait/nowait 126entry is applicable to datagram sockets only (other sockets should 127have a 128.Dq nowait 129entry in this space). If a datagram server connects 130to its peer, freeing the socket so 131.Nm inetd 132can received further messages on the socket, it is said to be 133a 134.Dq multi-threaded 135server, and should use the 136.Dq nowait 137entry. For datagram servers which process all incoming datagrams 138on a socket and eventually time out, the server is said to be 139.Dq single-threaded 140and should use a 141.Dq wait 142entry. 143.Xr Comsat 8 144.Pq Xr biff 1 145and 146.Xr talkd 8 147are both examples of the latter type of 148datagram server. 149.Xr Tftpd 8 150is an exception; it is a datagram server that establishes pseudo-connections. 151It must be listed as 152.Dq wait 153in order to avoid a race; 154the server reads the first packet, creates a new socket, 155and then forks and exits to allow 156.Nm inetd 157to check for new service requests to spawn new servers. 158.Pp 159The 160.Em user 161entry should contain the user name of the user as whom the server 162should run. This allows for servers to be given less permission 163than root. 164.Pp 165The 166.Em server-program 167entry should contain the pathname of the program which is to be 168executed by 169.Nm inetd 170when a request is found on its socket. If 171.Nm inetd 172provides this service internally, this entry should 173be 174.Dq internal . 175.Pp 176The 177.Em server program arguments 178should be just as arguments 179normally are, starting with argv[0], which is the name of 180the program. If the service is provided internally, the 181word 182.Dq internal 183should take the place of this entry. 184.Pp 185.Nm Inetd 186provides several 187.Dq trivial 188services internally by use of 189routines within itself. These services are 190.Dq echo , 191.Dq discard , 192.Dq chargen 193(character generator), 194.Dq daytime 195(human readable time), and 196.Dq time 197(machine readable time, 198in the form of the number of seconds since midnight, January 1991, 1900). All of these services are tcp based. For 200details of these services, consult the appropriate 201.Tn RFC 202from the Network Information Center. 203.Pp 204.Nm Inetd 205rereads its configuration file when it receives a hangup signal, 206.Dv SIGHUP . 207Services may be added, deleted or modified when the configuration file 208is reread. 209.Sh SEE ALSO 210.Xr comsat 8 , 211.Xr fingerd 8 , 212.Xr ftpd 8 , 213.Xr rexecd 8 , 214.Xr rlogind 8 , 215.Xr rshd 8 , 216.Xr telnetd 8 , 217.Xr tftpd 8 218.Sh HISTORY 219The 220.Nm 221command appeared in 222.Bx 4.3 . 223