cu(1)                                                       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  trans-
       fers with no error checking.

       cu  takes  a single argument, besides the options.  If the
       argument is the string "dir" cu will make a direct connec-
       tion  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 char-
       acter,  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  continues
            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 session.

       ~%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  print-
            ing  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  carriage
            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 default
            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).

       -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 num-
            ber 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 options.

       -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.

FILES
       The file name may be changed at compilation time, so  this
       is only an approximation.

       /etc/uucp/config - Configuration file.
       /etc/uucp/oldconfig/  -  Alternative configuration (HDB or
       V2 format)

AUTHOR
       Ian Lance Taylor <ian@airs.com>

                         Taylor UUCP 1.06                       1