TTYPROMPT - output a prompt to the terminal.

$*$TTYPrompt : stringexp

displays the value of the string expression "stringexp" on the terminal. EXEC does not start a new line after outputting the string; therefore, this can be used to prompt for input. For example,

$*$ttyprompt : now()+"> "

prompts for input using the current time and ">", as in

hh:mm:yy>

If an error occurs as EXEC evaluates the string expression, EXEC outputs an error message and sets the prompt to the null string "".