Provided by: cu_1.07-24_amd64 bug

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 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
            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 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).

       -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
            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.

AUTHOR

       Ian Lance Taylor <ian@airs.com>

                                                Taylor UUCP 1.07                                           cu(1)