CON(1) CON(1)
NAME
con, telnet, cu, rx, xms, xmr - remote login, execution, and
XMODEM file transfer
SYNOPSIS
con [ -dCrvs ] [ -l [ remuser ] ] [ -c cmd ] [net!]machine
telnet [ -dCrn ] [net!]machine
cu number
rx [ -n ] [net!]machine [ command-word ... ]
xms file
xmr file
DESCRIPTION
Con connects to the computer whose network address is
net!machine and logs in if possible. With no options, the
account name used on the remote system is the same as that
on the local system. Standard input and output go to the
local machine.
Options are:
-l with an argument causes remuser to be used as the
account name on the remote system. Without an argument
this option disables automatic login and a normal login
session ensues.
-C forces cooked mode, that is, local echo.
-c runs cmd as if it had been typed as a command from the
escape mode. This is used by cu.
-v (verbose mode) causes information about connection
attempts to be output to standard error. This can be
useful when trying to debug network connectivity.
-d causes debugging information to be output to standard
error.
-r suppresses printing of any carriage return followed by
a new line. This is useful since carriage return is a
printable character in Plan 9.
-s strips received characters to 7 bits to forestall mis-
interpretation of ASCII with parity as UTF.
Page 1 Plan 9 (printed 12/21/24)
CON(1) CON(1)
The control-\ character is a local escape. It prompts with
the local machine name and >>>. Legitimate responses to the
prompt are
i Send a quit [sic] signal to the remote machine.
q Exit.
b Send a break.
. Return from the escape.
!cmd Run the command with the network connection as its
standard input and standard output. Standard error
will go to the screen. This is useful for transmitting
and receiving files over the connections using programs
such as xms.
Telnet is similar to con, but uses the telnet protocol to
communicate with the remote machine. If standard input is a
file or a pipe, the -n option causes telnet not to hang up
the connection when it receives EOF on its standard input;
instead it waits for the remote end to hang up. It shares
con's -C, -d, and -r options.
Cu is a shell script that uses telco(4) and con to connect
to a machine via a modem. If the machine is equipped with a
local modem, it is used. Otherwise, the call is placed
through Datakit.
Rx executes one shell command on the remote machine as if
logged in there, but with local standard input and output.
A rudimentary shell environment is provided. If the target
is a Plan 9 machine, $service there will be rx.
Network addresses for both con and rx have the form
network!machine. Supported networks are those listed in
/net.
The commands xms and xmr respectively send and receive a
single file using the XMODEM protocol. They use standard
input and standard output for communication and are intended
for use with con.
EXAMPLES
rx kremvax cat file1 >file2
Copy remote file1 to local file2.
rx kremvax cat file1 '>file2'
Copy remote file1 to remote file2.
eqn paper | rx kremvax troff -ms | rx deepthought lp
Parallel processing: do each stage of a pipeline on a
different machine.
SOURCE
Page 2 Plan 9 (printed 12/21/24)
CON(1) CON(1)
/sys/src/cmd/con for con, xms, and xmr.
/sys/src/cmd/ip for telnet.
/rc/bin/cu
BUGS
Under rx, a program that should behave specially towards
terminals may not: e.g., remote shells will not prompt.
Also under rx, the remote standard error and standard output
are combined and go inseparably to the local standard out-
put.
Page 3 Plan 9 (printed 12/21/24)