DOS Command Ctty
Syntax:CTTY (device)
Purpose: Changes the standard I/O (Input/Output) device to an auxiliary device.
Discussion
The CTTY command is used only for I/O (input/output) devices such as a monitor. It cannot be used for peripheral devices such as a printer. However, DOS does not check to make sure you have entered a valid device name. If, for example, you specify a printer, DOS will attempt to read from the device, producing an error condition.Affects only programs that use standard DOS calls. BASIC and other programs that do not access I/O devices with DOS calls will not recognize device changes reset using this command.
Valid device names are:
AUX LPT
CLOCK$ LST
COM NUL
CON PRN
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