cu

cu(1) General Commands Manual cu(1)

NAME

   cu - Call up another system

SYNOPSIS

   cu [ options ] [ system | phone | "dir" ]

DESCRIPTION

   The cu command is used to call up another system and act as a dial in terminal.  It can also do simple file transfers with no error checking.

   cu takes a single argument, besides the options.  If the argument is the string "dir" cu will make a direct connection to the port.  This may only be used by
   users with write access to the port, as it permits reprogramming the modem.

   Otherwise, if the argument begins with a digit, it is taken to be a phone number to call.  Otherwise, it is taken to be the name of a system to call.  The -z
   or  --system  option may be used to name a system beginning with a digit, and the -c or --phone option may be used to name a phone number that does not begin
   with a digit.

   cu locates a port to use in the UUCP configuration files.  If a simple system name is given, it will select a port appropriate  for  that  system.   The  -p,
   --port, -l, --line, -s and --speed options may be used to control the port selection.

   When  a connection is made to the remote system, cu forks into two processes.  One reads from the port and writes to the terminal, while the other reads from
   the terminal and writes to the port.

   cu provides several commands that may be used during the conversation.  The commands all begin with an escape character, initially  ~  (tilde).   The  escape
   character  is only recognized at the beginning of a line.  To send an escape character to the remote system at the start of a line, it must be entered twice.
   All commands are either a single character or a word beginning with % (percent sign).

   cu recognizes the following commands:

   ~.   Terminate the conversation.

   ~! command
        Run command in a shell.  If command is empty, starts up a shell.

   ~$ command
        Run command, sending the standard output to the remote system.

   ~| command
        Run command, taking the standard input from the remote system.

   ~+ command
        Run command, taking the standard input from the remote system and sending the standard output to the remote system.

   ~#, ~%break
        Send a break signal, if possible.

   ~c directory, ~%cd directory
        Change the local directory.

   ~> file
        Send a file to the remote system.  This just dumps the file over the communication line.  It is assumed that the remote system is expecting it.

   ~<   Receive a file from the remote system.  This prompts for the local file name and for the remote command to execute to begin the file transfer.  It  con‐
        tinues accepting data until the contents of the eofread variable are seen.

   ~p from to, ~%put from to
        Send a file to a remote Unix system.  This runs the appropriate commands on the remote system.

   ~t from to, ~%take from to
        Retrieve a file from a remote Unix system.  This runs the appropriate commands on the remote system.

   ~s variable value
        Set a cu variable to the given value.  If value is not given, the variable is set to true.

   ~! variable
        Set a cu variable to false.

   ~z   Suspend  the  cu session.  This is only supported on some systems.  On systems for which ^Z may be used to suspend a job, ~^Z will also suspend the ses‐
        sion.

   ~%nostop
        Turn off XON/XOFF handling.

   ~%stop
        Turn on XON/XOFF handling.

   ~v   List all the variables and their values.

   ~?   List all commands.

        cu also supports several variables.  They may be listed with the ~v command, and set with the ~s or ~!  commands.

   escape
        The escape character.  Initially ~ (tilde).

   delay
        If this variable is true, cu will delay for a second after recognizing the escape character before printing the name of the local system.   The  default
        is true.

   eol  The  list of characters which are considered to finish a line.  The escape character is only recognized after one of these is seen.  The default is car‐
        riage return, ^U, ^C, ^O, ^D, ^S, ^Q, ^R.

   binary
        Whether to transfer binary data when sending a file.  If this is false, then newlines in the file being sent are converted to carriage returns.  The de‐
        fault is false.

   binary-prefix
        A string used before sending a binary character in a file transfer, if the binary variable is true.  The default is ^V.

   echo-check
        Whether to check file transfers by examining what the remote system echoes back.  This probably doesn't work very well.  The default is false.

   echonl
        The character to look for after sending each line in a file.  The default is carriage return.

   timeout
        The  timeout to use, in seconds, when looking for a character, either when doing echo checking or when looking for the echonl character.  The default is
        30.

   kill The character to use delete a line if the echo check fails.  The default is ^U.

   resend
        The number of times to resend a line if the echo check continues to fail.  The default is 10.

   eofwrite
        The string to write after sending a file with the ~> command.  The default is ^D.

   eofread
        The string to look for when receiving a file with the ~< command.  The default is $, which is intended to be a typical shell prompt.

   verbose
        Whether to print accumulated information during a file transfer.  The default is true.

OPTIONS

   The following options may be given to cu.

   -e, --parity=even
        Use even parity.

   -o, --parity=odd
        Use odd parity.

   --parity=none
        Use no parity.  No parity is also used if both -e and -o are given.

   -h, --halfduplex
        Echo characters locally (half-duplex mode).

   --nostop
        Turn off XON/XOFF handling (it is on by default).

   -f, --nortscts
        Do not use hardware flow control.

   -E char, --escape char
        Set the escape character.  Initially ~ (tilde).  To eliminate the escape character, use -E ''.

   -z system, --system system
        The system to call.

   -c phone-number, --phone phone-number
        The phone number to call.

   -p port, --port port
        Name the port to use.

   -a port
        Equivalent to --port port.

   -l line, --line line
        Name the line to use by giving a device name.  This may be used to dial out on ports that are not listed in the UUCP configuration files.  Write  access
        to the device is required.

   -s speed, --speed speed
        The speed (baud rate) to use.

   -#   Where # is a number, equivalent to --speed #.

   -n, --prompt
        Prompt for the phone number to use.

   -d   Enter debugging mode.  Equivalent to --debug all.

   -x type, --debug type
        Turn  on particular debugging types.  The following types are recognized: abnormal, chat, handshake, uucp-proto, proto, port, config, spooldir, execute,
        incoming, outgoing.  Only abnormal, chat, handshake, port, config, incoming and outgoing are meaningful for cu.

        Multiple types may be given, separated by commas, and the --debug option may appear multiple times.  A number may also be given, which will turn on that
        many types from the foregoing list; for example, --debug 2 is equivalent to --debug abnormal,chat.  --debug all may be used to turn on all debugging op‐
        tions.

   -I file, --config file
        Set configuration file to use.  This option may not be available, depending upon how cu was compiled.

   -v, --version
        Report version information and exit.

   --help
        Print a help message and exit.

BUGS

   This program does not work very well.

AUTHOR

   Ian Lance Taylor <ian@airs.com>

                                                                      Taylor UUCP 1.07                                                                     cu(1)