inetd linux command

inetd

inetd [option] [configuration_file]

TCP/IP command. Internet services daemon. inetd listens on multiple ports for incoming connection requests. When it receives one, it spawns the appropriate server. When started, inetd reads its configuration information from either configuration_file, or from the default configuration file /etc/inetd.conf. It then issues a call to getservbyname, creates a socket for each server, and binds each socket to the port for that server. It does a listen on all connection-based sockets, then waits, using select for a connection or datagram.

When a connection request is received on a listening socket, inetd does an accept, creating a new socket. It then forks, dups, and execs the appropriate server. The invoked server has I/O to stdin, stdout, and stderr done to the new socket, connecting the server to the client process.

When there is data waiting on a datagram socket, inetd forks, dups, and execs the appropriate server, passing it any server program arguments. A datagram server has I/O to stdin, stdout, and stderr done to the original socket. If the datagram socket is marked as wait, the invoked server must process the message before inetd considers the socket available for new connections. If the socket is marked nowait, inetd continues to process incoming messages on that port.

The following servers may be started by inetd: bootpd, bootpgw, fingerd, ftpd, imapd, popd, rexecd, rlogind, rshd, talkd, telnetd, and tftpd. Do not arrange for inetd to start named, routed, rwhod, sendmail, listen, or any NFS server.

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.

Option

-d

Turn on socket-level debugging and print debugging information to stdout.

Files

/etc/inetd.conf

Default configuration file.

/var/run/inetd.pid

inetd's process ID.