NAME
inetd - internet "super-server"

SYNOPSIS
/usr/etc/inetd [ -d ] [ configuration file ]

DESCRIPTION
Inetd should be run at boot time by /etc/rc. It then listens for
connections on certain internet sockets. When a connection is
found on one of its sockets, it decides what service the socket
corresponds to, and invokes a program to service the request.
After the program is finished, it continues to listen on the socket
(except in some cases which will be described below). Essentially,
inetd allows running one daemon to invoke several others, reducing
load on the system.

Upon execution, inetd reads its configuration information from a
configuration file which, by default, is /etc/inetd.conf. There
must be an entry for each field of the configuration file, with
entries for each field separated by a tab or a space. Comments are
denoted by a "#" at the beginning of a line. There must be an
entry for each field. The fields of the configuration file are as
follows:
service name
socket type
protocol
wait/nowait
user
server program
server program arguments

The service name entry is the name of a valid service in the file
/etc/services/. For "internal" services (discussed below), the
service name must be the official name of the service (that is, the
first entry in /etc/services).

The socket type should be one of "stream", "dgram", "raw",
"rdm", or "seqpacket", depending on whether the socket is a
stream, datagram, raw, reliably delivered message, or sequenced
packet socket.

The protocol must be a valid protocol as given in /etc/protocols.
Examples might be "tcp" or "udp".

The wait/nowait entry is applicable to datagram sockets only (other
sockets should have a "nowait" entry in this space). If a
datagram server connects to its peer, freeing the socket so inetd
can received further messages on the socket, it is said to be a
"multi-threaded" server, and should use the "nowait" entry.
For datagram servers which process all incoming datagrams on a
socket and eventually time out, the server is said to be "single-
threaded" and should use a "wait" entry. Comsat(8) (biff(1)) and
talk(1) are both examples of the latter type of datagram server.

The user entry should contain the user name of the user as whom the
server should run. This allows for servers to be given less
permission than root. The server program entry should contain the
pathname of the program which is to be executed by inetd when a
request is found on its socket. If inetd provides this service
internally, this entry should be "internal".

The arguments to the server program should be just as they normally
are, starting with argv[0], which is the name of the program. If
the service is provided internally, the word "internal" should
take the place of this entry.

Inetd provides several "trivial" services internally by use of
routines within itself. These services are "echo", "discard",
"chargen" (character generator), "daytime" (human readable
time), and "time" (machine readable time, in the form of the
number of seconds since midnight, January 1, 1900). All of these
services are tcp based. For details of these services, consult the
appropriate RFC from the Network Information Center. (See "FYI on
Where to Start - A Bibliography of Internetworking Information"
(RFC1175) in the MachTen System & Network Administration manual.)

Inetd rereads its configuration file when it receives a hangup
signal, SIGHUP. Services may be added, deleted or modified when
the configuration file is reread.

SEE ALSO
comsat(8), ftpd(8), rexecd(8), rlogind(8), rshd(8), tcptraffic(8),
telnetd(8)