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 90To specify an 91.Em Sun-RPC 92based service, the entry would contain these fields. 93.Pp 94.Bd -unfilled -offset indent -compact 95service name/version 96socket type 97rpc/protocol 98wait/nowait 99user 100server program 101server program arguments 102.Ed 103.Pp 104The 105.Em service-name 106entry is the name of a valid service in 107the file 108.Pa /etc/services . 109For 110.Dq internal 111services (discussed below), the service 112name 113.Em must 114be the official name of the service (that is, the first entry in 115.Pa /etc/services ) . 116When used to specify a 117.Em Sun-RPC 118based service, this field is a valid RPC service name in 119the file 120.Pa /etc/rpc . 121The part on the right of the 122.Dq / 123is the RPC version number. This 124can simply be a single numeric argument or a range of versions. 125A range is bounded by the low version to the high version - 126.Dq rusers/1-3 . 127 128.Pp 129The 130.Em socket-type 131should be one of 132.Dq stream , 133.Dq dgram , 134.Dq raw , 135.Dq rdm , 136or 137.Dq seqpacket , 138depending on whether the socket is a stream, datagram, raw, 139reliably delivered message, or sequenced packet socket. 140.Pp 141The 142.Em protocol 143must be a valid protocol as given in 144.Pa /etc/protocols . 145Examples might be 146.Dq tcp 147or 148.Dq udp . 149Rpc based services are specified with the 150.Dq rpc/tcp 151or 152.Dq rpc/udp 153service type. 154 155.Pp 156The 157.Em wait/nowait 158entry is applicable to datagram sockets only (other sockets should 159have a 160.Dq nowait 161entry in this space). If a datagram server connects 162to its peer, freeing the socket so 163.Nm inetd 164can received further messages on the socket, it is said to be 165a 166.Dq multi-threaded 167server, and should use the 168.Dq nowait 169entry. For datagram servers which process all incoming datagrams 170on a socket and eventually time out, the server is said to be 171.Dq single-threaded 172and should use a 173.Dq wait 174entry. 175.Xr Comsat 8 176.Pq Xr biff 1 177and 178.Xr talkd 8 179are both examples of the latter type of 180datagram server. 181.Xr Tftpd 8 182is an exception; it is a datagram server that establishes pseudo-connections. 183It must be listed as 184.Dq wait 185in order to avoid a race; 186the server reads the first packet, creates a new socket, 187and then forks and exits to allow 188.Nm inetd 189to check for new service requests to spawn new servers. 190.Pp 191The 192.Em user 193entry should contain the user name of the user as whom the server 194should run. This allows for servers to be given less permission 195than root. 196.Pp 197The 198.Em server-program 199entry should contain the pathname of the program which is to be 200executed by 201.Nm inetd 202when a request is found on its socket. If 203.Nm inetd 204provides this service internally, this entry should 205be 206.Dq internal . 207.Pp 208The 209.Em server program arguments 210should be just as arguments 211normally are, starting with argv[0], which is the name of 212the program. If the service is provided internally, the 213word 214.Dq internal 215should take the place of this entry. 216.Pp 217.Nm Inetd 218provides several 219.Dq trivial 220services internally by use of 221routines within itself. These services are 222.Dq echo , 223.Dq discard , 224.Dq chargen 225(character generator), 226.Dq daytime 227(human readable time), and 228.Dq time 229(machine readable time, 230in the form of the number of seconds since midnight, January 2311, 1900). All of these services are tcp based. For 232details of these services, consult the appropriate 233.Tn RFC 234from the Network Information Center. 235.Pp 236.Nm Inetd 237rereads its configuration file when it receives a hangup signal, 238.Dv SIGHUP . 239Services may be added, deleted or modified when the configuration file 240is reread. 241.Sh SEE ALSO 242.Xr comsat 8 , 243.Xr fingerd 8 , 244.Xr ftpd 8 , 245.Xr rexecd 8 , 246.Xr rlogind 8 , 247.Xr rshd 8 , 248.Xr telnetd 8 , 249.Xr tftpd 8 250.Sh HISTORY 251The 252.Nm 253command appeared in 254.Bx 4.3 . 255Support for 256.Em Sun-RPC 257based services is modelled after that 258provided by 259.Em Sun-OS 4.1 . 260