( --
char )
Receive one character
char, a member of the
implementation-defined character set. Keyboard events that do
not correspond to such characters are discarded until a valid
character is received, and those events are subsequently
unavailable.
All standard characters can be received. Characters received by
KEY are not displayed.
Any standard character returned by
KEY has the numeric
value specified in
3.1.2.1 Graphic characters.
Programs that require the ability to receive control characters
have an environmental dependency.