LISTEN(8) LISTEN(8)
NAME
listen, il7, il9, il19, il565, il566, il17007, il17008,
il17009, il17013, il17031, tcp7, tcp9, tcp19, tcp21, tcp23,
tcp25, tcp53, tcp110, tcp113, tcp143, tcp513, tcp515,
tcp564, tcp565, tcp566, tcp567, tcp993, tcp17007, tcp17009,
tcp17013 - listen for calls on a network device
SYNOPSIS
aux/listen [-q] [-d srvdir] [-t trustsrvdir] [net [name]]
DESCRIPTION
listen announces itself to a network as name (by default the
contents of /env/sysname) and listens for inbound calls to
local services. Net is the network protocol on which to
listen, by default /net/il. The services available are exe-
cutable files in srvdir or trustsrvdir. If neither srvdir
nor trustsrvdir is given, listen looks for executable files
in /bin/service. Services found in srvdir are executed as
user none; services found in trustsrvdir as executed as the
user who started listen. Option -q suppresses affirmative
log information.
Service names are made by concatenating the name of the net-
work with the name of the service or port. For example, an
inbound call on the TCP network for port 565 executes ser-
vice tcp565.
The following services are available in /bin/service.
il19 tcp19 chargen service.
il17007 tcp17007 serve a piece of the name space using the
Plan 9 file system protocol, with authen-
tication (typically used by cpu(1)).
tcp564 like 17007, without authentication (used
by Unix systems to see Plan 9 files).
il17008 like 17007, but serves the root of the
tree, forgoing the negotiation for which
subtree to serve.
il17009 tcp17009 remote execution.
il17013 tcp17013 server for cpu(1) command.
il17031 server for ramfs(4).
il565 tcp565 report the address of the incoming call.
tcp21 FTP daemon
tcp515 LP daemon; see lp(8).
tcp23 telnet terminal connection.
tcp25 mail delivery.
tcp513 rlogin terminal connection.
il7 tcp7 echo any bytes received (bit mirror)
il9 tcp9 consume any bytes received (bit bucket)
tcp53 TCP port for DNS.
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LISTEN(8) LISTEN(8)
tcp110 POP3 port.
tcp143 IMAP4rev1 port.
tcp113 Ident port (always reports none).
tcp567 Plan 9 ticket service.
The following services are available in /bin/service.auth.
tcp566 check a SecureNet box.
il566 authentication requests.
tcp993 Secure IMAP4rev1 port.
FILES
/net/il by convention, IL device bind point
/net/tcp by convention, TCP device bind point
/env/sysname default announced name
SOURCE
The source to listen is in /sys/src/cmd/aux/listen.c. The
other commands are rc(1) scripts in /rc/bin/service.
SEE ALSO
auth(6), dial(2)
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