update

Task/Keyboard-input-Keypress-check/Racket/keyboard-input-keypress-check.rkt

@@ -0,0 +1,15 @@
+#lang racket
+(define-syntax-rule (with-raw body ...)
+  (let ([saved #f])
+    (define (stty x) (system (~a "stty " x)) (void))
+    (dynamic-wind (λ() (set! saved (with-output-to-string (λ() (stty "-g"))))
+                       (stty "raw -echo opost"))
+                  (λ() body ...)
+                  (λ() (stty saved)))))
+
+(with-raw
+  (printf "Press a key, or not\n")
+  (sleep 2)
+  (if (char-ready?)
+    (printf "You pressed ~a\n" (read-char))
+    (printf "You didn't press a key\n")))