LISTEN(8) LISTEN(8)
NAME
listen, dkcpu, dkcpunote, dkdiscard, dkecho, dkexportfs,
dkexportfs0, dkrexexec, dkwhoami, dksmtp, dkdcon, dklogin,
dkfsauth, dkrexauth, dkchal, dkchangekey, dkcheck, dkguard,
il7, il9, il565, il17005, il17006, il17007, il17009,
il17020, il17021, il17022, il17023, il17024, tcp7, tcp9,
tcp21, tcp23, tcp25, tcp513, tcp565, tcp17007, tcp17008,
tcp6000 - 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 device on which to lis-
ten, by default /net/dk. 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, while a call on the Datakit network for service
whoami executes service dkwhoami. Services are executed
with the name of the service, the network name, and the
stream directory of the incoming call as arguments.
The following services are available in /bin/service.
dkcpu il17005 server for cpu(1) command.
dkcpunote il17006 /proc/pid/notify forwarding for
cpu(1).
dkexportfs il17007 tcp17007
serve a piece of the name space using
the Plan 9 file system protocol, with
authentication (typically used by
cpu(1)).
dkexportfs0 il17008 tcp17008
like 17007, without authentication
(used by Unix systems to see Plan 9
files).
dkrexexec il17009 remote execution.
dkwhoami il565 tcp565 report the address of the incoming
call.
tcp21 FTP daemon
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LISTEN(8) LISTEN(8)
tcp6000 X-window callback
dksmtp tcp25 mail delivery.
dkdcon research Unix terminal connection.
dklogin generic terminal connection.
tcp23 telnet terminal connection.
tcp513 rlogin terminal connection.
dkecho il7 tcp7 echo any bytes received (bit mirror)
dkdiscard il9 tcp9 consume any bytes received (bit
bucket)
The following services are available in /bin/service.auth.
dkfsauth il17020 file system authentication.
dkrexauth il17021 remote execution authentication.
dkchangekey il17022 change a user's password.
dkchal il17023 SecureNet CPU authentication.
dkcheck il17024 check a user's password.
dkguard check a SecureNet box.
FILES
/net/dk by convention, Datakit device bind point
/net/il by convention, IL device bind point
/net/tcp by convention, TCP device bind point
/env/sysname default announced name
SEE ALSO
dkconfig(8), auth(6), dk(3), dial(2)
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