PutCode1
Implements ISO's put_code/1: writes the character coded by the integer argument to the current output stream (see IOPrimitiveUtils.currentOutputChannel).
Throws
if the argument is unbound.
(character_code) if it is bound but not an integer.
(character_code) if it is an integer outside the representable character-code range.
Fails, rather than erroring, if the channel is closed.