cu Description
--------------

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

   The `cu' program 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.

   The `cu' program takes a single non-option argument.

   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' options may be used to name a system
beginning with a digit, and the `-c' or `--phone' options may be used
to name a phone number that does not begin with a digit.

   The `cu' program 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.