[plt-scheme] basic question about display + read + threads

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let's say in mzscheme I've got one thread displaying some stuff every so
often. well, here, a more concrete example:

lessay I do this:
(define (blah) (sleep 5) (display "HI!\n") (blah))
(thread blah)
(read)

is there any way to do something like that, but in such a way that
instead of, say, when typing text on the read line, ending up with
"ThHI!is is the teHI!xt I aHI!m enteHI!ring", all the text entry line
and all the text already on it gets "pushed down" a line each time text
is displayed, so that instead the text in the display thread will always
display above the input line, as opposed to in the middle of it?

Thanks.

Psy-Kosh

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