inetd(1M)                                               inetd(1M)



NAME
     inetd - starts Internet servers when needed

SYNOPSIS
     inetd [-d]

ARGUMENTS
     -d   Turns on debugging traces for connection-oriented
          Transmission Control Protocol (TCP) servers.

DESCRIPTION
     inetd is the Internet superserver that invokes all Internet
     servers when needed. The inetd daemon is started from
     /etc/inittab by init when the system is started up.

     When started, inetd reads /etc/services and supports the
     services that are listed there.

     The format of entries in /etc/servers for Remote Procedure
     Call (RPC) services is as follows:

        rpc protocol program RPC-program-number version-number

     where protocol can be udp or tcp, program is the full
     pathname of the program that implements the server, and
     RPC-program-number and version-number are the RPC program
     and version numbers, respectively, of the service.

     If the same program handles multiple versions, the version
     number can be specified as a range:

        rpc udp /usr/etc/rstatd 100001 1-2

     Each time a request for a connection arrives, inetd invokes
     the appropriate connection service by creating a process and
     passing to it a file descriptor of 0 and an argument of the
     form sourcehost.sourceport.  The sourcehost part of the
     argument is hexadecimal and sourceport is decimal.

     When a datagram arrives, inetd invokes the appropriate
     datagram-oriented service by creating a process and passing
     to it a file descriptor of 0.  The inetd daemon does not
     check the socket where datagrams arrive for a new datagram
     until the process completes.  Such processes read the
     incoming datagram and then fork and exit or handle the
     arriving datagram and then time out.

Writing an RPC server
     You can use inetd to start an RPC server.  The first
     difference from the usual code is that the function
     svcudp_create should be called as shown here, because inetd
     passes a socket file as descriptor 0:



January 1992                                                    1

inetd(1M)                                               inetd(1M)



        transp = scvudp_create(0)

     The second difference is that svc_register should be called
     as shown here:

        svc_register(PROGNUM, VERSNUM, service, transp, 0)

     The last argument is 0 because the program is already
     registered by inetd.  You must explicitly exit from the
     server process to return control to inetd, because scv_run
     never returns.

LIMITATIONS
     There is no way to invoke TCP debugging-packet tracing on a
     per-service basis.

     The inetd daemon should reread the /etc/servers file on
     receipt of a SIGHUP signal.

     The /etc/servers file can have no more than 26 entries.

FILES
     /etc/inetd
          Executable file
     /etc/servers
          File containing the list of Internet server processes

SEE ALSO
     fingerd(1M), ftpd(1M), init(1M), remshd(1M), rexecd(1M),
     rlogind(1M), talkd(1M), telnetd(1M), tftpd(1M)

     servers(4) in A/UX Programmer's Reference























2                                                    January 1992