Convert multi-LETREC to internal definitions in thread.scm.

diff --git a/src/runtime/thread.scm b/src/runtime/thread.scm
index a03d5639a163188f1064dcc1a0b6b4146d9ab75b..d030a2925296d0c0d23a7ebeff5ab24ca60a24a0 100644 (file)
--- a/src/runtime/thread.scm
+++ b/src/runtime/thread.scm
@@ -674,30 +674,28 @@ USA.
 (define (permanently-register-io-thread-event descriptor mode thread event)
   (let ((stop? #f)
        (registration #f))
-    (letrec ((handler
-             (named-lambda (permanent-io-event mode*)
-               (if (not stop?)
-                   (event mode*))
-               (if (not (or stop? (memq mode* '(error hangup #f))))
-                   (register))))
-            (register
-             (lambda ()
-               (deregister)
-               (if (not stop?)
-                   (set! registration
-                         (register-io-thread-event descriptor mode
-                                                   thread handler)))))
-            (deregister
-             (lambda ()
-               (if registration
-                   (begin
-                     (deregister-io-thread-event registration)
-                     (set! registration #f))))))
-      (register)
-      (cons 'deregister-permanent-io-event
-           (lambda ()
-             (set! stop? #t)
-             (deregister))))))
+    (define handler
+      (named-lambda (permanent-io-event mode*)
+       (if (not stop?)
+           (event mode*))
+       (if (not (or stop? (memq mode* '(error hangup #f))))
+           (register))))
+    (define (register)
+      (deregister)
+      (if (not stop?)
+         (set! registration
+               (register-io-thread-event descriptor mode
+                                         thread handler))))
+    (define (deregister)
+      (if registration
+         (begin
+           (deregister-io-thread-event registration)
+           (set! registration #f))))
+    (register)
+    (cons 'deregister-permanent-io-event
+         (lambda ()
+           (set! stop? #t)
+           (deregister)))))
 
 (define (register-io-thread-event descriptor mode thread event)
   (guarantee-select-mode mode 'register-io-thread-event)