CTTY (Change Console) COMMAND

Purpose:   Changes standard input/output from a console for an auxiliary one
           or sets a keyboard and a screen as a standard device of
           input/output.

Syntax:    CTTY device's name

Type:      Internal command

Parameters:
     The name of a device defines the type of the device, used as a system
console. Specifying AUX, COM1 or COM2, makes these devices to be the system
ones. Specifying the CON device restores the keyboard and the screen as the
system I/O  devices.

Notes:
1. The CTTY command adopts the name of any character device, providing the
   possibility to use inhouse device servicing programs. Nevertheless, it is
   important to make sure that a given device may be used both for input and
   output. For this reason, a printing device may not be specified, as it
   can't be used for input.
2. The CTTY command runs only in programs, that use standard DOS functions.
   Other programs, like BASIC (i.e. those, where there are no DOS functions
   call ) can not use the CTTY command for changing the standard I/O
   device.

Examples:
1. The following command defines the AUX device to be the standard I/O
device:

     A>CTTY AUX

2. The CTTY command restores the keyboard and the screen, as the standard
I/O devices:

     A>CTTY CON