diff --git a/racket/src/io/sandman/main.rkt b/racket/src/io/sandman/main.rkt
index 8d9bd41c08..495b92edbf 100644
--- a/racket/src/io/sandman/main.rkt
+++ b/racket/src/io/sandman/main.rkt
@@ -96,6 +96,7 @@
                                         [(eqv? v RKTIO_OS_SIGNAL_HUP) 'hang-up]
                                         [(eqv? v RKTIO_OS_SIGNAL_TERM) 'terminate]
                                         [else 'break]))
+           (wakeup #f)
            (check-signals)))
        (when (fd-semaphore-poll-ready?)
          (wakeup #f))