Don't log to stderr if logfile cannot be opened.

Removes problem with make-logfile-rotator and closing stderr.

httpd-core.scm

@@ -114,6 +114,8 @@
 	  (force-output (http-log-port))
 	  (release-lock http-log-lock)))))
 
+
+;; does the logfile rotation on signal USR1
 (define (make-logfile-rotator logfile http-log-lock)
   (set-interrupt-handler interrupt/usr1 #f)
   (lambda ()
@@ -129,11 +131,10 @@
   (with-errno-handler*
    (lambda (errno packet)
      (format (current-error-port) 
-	     "[httpd] Warning: An error occured while opening ~S for writing (~A).
-                 Logging now to stderr.~%"
+	     "[httpd] Warning: An error occured while opening ~S for writing (~A).~%Send signal USR1 when the problem is fixed.~%"
 	     logfile
 	     (car packet))
-     (current-error-port))
+     (make-null-output-port))
    (lambda ()
      (open-output-file logfile 
 		       (bitwise-ior open/create open/append)))))