The inetd(1)
daemon, which can be run either as a conventional UNIX daemon or as
a Windows service, is a "super server" for Internet programs. It
acts as an intermediary for programs such as telnet(1),
rlogin(1),
rcp(1), and
ftp(1). When
a client computer uses any of these programs to access the server,
inetd detects the request and starts the corresponding
service on the server.
Technically, inetd listens for remote connections to TCP/IP sockets with well-known addresses. Each well-known address is associated with a specific service. For example, ftp is associated with port 21, telnet with port 23, and so on. Once inetd detects a remote request, it starts the appropriate service.
The inetd service only starts the server-side daemon or
service; it does not start a client. For example, assume that you
run inetd. When a user uses Telnet to connect to your
computer, inetd starts telnetd(1)
so that the remote user can connect to your computer. The remote
user must already be using a Telnet client.
This section covers: