.TH LISTEN 8
.SH 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
.SH SYNOPSIS
.B aux/listen
.RB [ -q ]
.RB [ -d
.IR srvdir ]
.RB [ -t
.IR trustsrvdir ]
.RI[ net
.RI [ name ]]
.SH DESCRIPTION
.I listen
announces itself to a network as
.I name
(by default the contents of
.BR /env/sysname )
and listens for inbound calls to local services.
.I Net
is the network protocol on which to listen, by default
.BR /net/il .
The services available are executable files in
.I srvdir
or
.IR trustsrvdir .
If neither
.I srvdir
nor
.I trustsrvdir
is given,
.I listen
looks for executable files in
.BR /bin/service .
Services found in
.I srvdir
are executed as user
.BR none ;
services found in
.I trustsrvdir
as executed as the user who started
.IR listen .
Option
.B -q
suppresses affirmative log information.
.PP
Service names are made by concatenating the name of
the network with the name of the service or port.
For example,
an inbound call on the TCP network for port 565 executes service
.BR tcp565 .
.PP
The following services are available in
.BR /bin/service .
.TF il17005\ tcp17005
.TP
.B il19 tcp19
.B chargen
service.
.TP
.B il17007 tcp17007
serve a piece of the name space using the Plan 9 file system protocol,
with authentication (typically used by
.IR cpu (1)).
.TP
.B tcp564
like 17007, without authentication (used by Unix
systems to see Plan 9 files).
.TP
.B il17008
like 17007, but serves the root of the tree, forgoing the negotiation for which subtree to serve.
.TP
.B il17009 tcp17009
remote execution.
.TP
.B "il17013 tcp17013"
server for
.IR cpu (1)
command.
.TP
.B il17031
server for
.IR ramfs (4).
.TP
.B il565 tcp565
report the address of the incoming call.
.TP
.B tcp21
FTP daemon
.TP
.B tcp515
LP daemon; see
.IR lp (8).
.TP
.B tcp23
.B telnet
terminal connection.
.TP
.B tcp25
mail delivery.
.TP
.B tcp513
.B rlogin
terminal connection.
.TP
.B il7 tcp7
echo any bytes received (bit mirror)
.TP
.B il9 tcp9
consume any bytes received (bit bucket)
.TP
.B tcp53
TCP port for DNS.
.TP
.B tcp110
POP3 port.
.TP
.B tcp143
IMAP4rev1 port.
.TP
.B tcp113
.B Ident
port (always reports
.BR none ).
.TP
.B tcp567
Plan 9 ticket service.
.PD
.PP
The following services are available in
.BR /bin/service.auth .
.TF il565\ tcp565
.TP
.B tcp566
check a SecureNet box.
.TP
.B il566
authentication requests.
.TP
.B tcp993
Secure IMAP4rev1 port.
.SH FILES
.TF /env/sysname
.TP
.B /net/il
by convention, IL device bind point
.TP
.B /net/tcp
by convention, TCP device bind point
.TP
.B /env/sysname
default announced name
.SH SOURCE
The source to
.I listen
is in
.BR /sys/src/cmd/aux/listen.c .
The other commands are
.IR rc (1)
scripts in
.BR /rc/bin/service .
.SH "SEE ALSO"
.IR auth (6),
.IR dial (2)
