harvesting external-process output in OpenMCL 0.13 broken

Beginning with OpenMCL 0.13, a lisp process (the value of
CCL::*EXTERNAL-PROCESS-WATCHDOG*) is supposed to watch for the termination
status of external processes (created via #'RUN-PROGRAM) and to handle
redirected I/O to and from those external processes.

The lisp watchdog process is supposed to only be active (considered by
the scheduler) when it "has something to do"; in 0.13, it deactivates
itself prematurely in some cases.  This in turn can cause RUN-PROGRAM
to wait indefinitely for pending output; the example from the "run-program"
documentation page:

(with-output-to-string (stream)
  (run-program "uname" '("-r") :output stream))

will often hang as a result.

Interrupting it via ^C, calling

1> (ccl::watch-file-descriptors)

and

1> (continue)

in the break loop will "harvest" the pending output and allow the
call to RUN-PROGRAM to return.

The enclosed patch should cause the watchdog process to remain active
as long as it has some work to do.

Index: level-1/l1-boot-3.lisp
===================================================================
RCS file: /usr/local/publiccvs/ccl/level-1/l1-boot-3.lisp,v
retrieving revision 1.3
diff -u -r1.3 l1-boot-3.lisp
--- level-1/l1-boot-3.lisp	7 Aug 2002 07:46:44 -0000	1.3
+++ level-1/l1-boot-3.lisp	31 Aug 2002 05:34:40 -0000
@@ -26,12 +26,10 @@
   (process-preset *external-process-watchdog*
 		  #'(lambda ()
 		      (loop
-			(process-wait "external-process"
-				      #'(lambda ()
-					  (not (null *external-processes*))))
 			(watch-file-descriptors)
 			(check-all-pids)
-			(when (null *external-processes*)
+			(when (and (null *external-processes*)
+				   (null *watched-fd-handlers*))
 			  (process-enable-arrest-reason *current-process*))))))
 
 (catch :toplevel