Device 1 Details

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Output. Device 1 output is similar to device 0 for output, but form feeds and tabs are not handled. They are displayed as characters instead.


Input. For device 1 input, keystrokes are not echoed on the screen, although a flashing cursor is displayed. There is no buffer, so keystrokes are sent to the program as soon as they are struck. If a non-ASCII key is struck, such as F1, a zero is returned. If ChIn(1) is called a second time, it returns the key's DOS scan code. This is the scan code described in the standard XPL0 manual. Typing Ctrl+C aborts the program.


(Note: Intrinsic 104 GetScanCode is also available, which captures all scan codes including those for the Ctrl, Shift and Alt keys.)


Initialization. OpenI(1) discards any pending keystrokes.