diff --git a/src/mzscheme/src/port.c b/src/mzscheme/src/port.c
index 190a2cd1c3..bea8dd121d 100644
--- a/src/mzscheme/src/port.c
+++ b/src/mzscheme/src/port.c
@@ -6483,10 +6483,10 @@ static void init_sigchld(void)
   }
 }
 
-int scheme_check_child_done()
+static void check_child_done()
 {
   pid_t result;
-  int status, did_one = 0;
+  int status;
   System_Child *sc, *prev;
 
   if (scheme_system_children) {
@@ -6511,15 +6511,11 @@ int scheme_check_child_done()
               prev->next = sc->next;
             } else
               scheme_system_children = sc->next;
-            
-            did_one = 1;
           }
         }
       }
     } while (result > 0);
   }
-
-  return did_one;
 }
 
 #endif
@@ -6679,6 +6675,7 @@ static int subp_done(Scheme_Object *sp)
 
 #if defined(UNIX_PROCESSES)
   System_Child *sc = (System_Child *)sci;
+  check_child_done();
   return sc->done;
 #endif
 #ifdef WINDOWS_PROCESSES
@@ -6717,6 +6714,8 @@ static Scheme_Object *subprocess_status(int argc, Scheme_Object **argv)
 #if defined(UNIX_PROCESSES)
     System_Child *sc = (System_Child *)sp->handle;
 
+    check_child_done();
+
     if (sc->done)
       status = sc->status;
     else
@@ -6789,6 +6788,8 @@ static Scheme_Object *subprocess_kill(int argc, Scheme_Object **argv)
     {
       System_Child *sc = (System_Child *)sp->handle;
 
+      check_child_done();
+
       while (1) {
 	if (sc->done)
 	  return scheme_void;
diff --git a/src/mzscheme/src/thread.c b/src/mzscheme/src/thread.c
index caedd074cf..9ee76d7270 100644
--- a/src/mzscheme/src/thread.c
+++ b/src/mzscheme/src/thread.c
@@ -95,10 +95,6 @@ extern HANDLE scheme_break_semaphore;
 
 #include "schfd.h"
 
-#if defined(UNIX_PROCESSES)
-extern int scheme_check_child_done();
-#endif
-
 #define DEFAULT_INIT_STACK_SIZE 1000
 #define MAX_INIT_STACK_SIZE 100000
 
@@ -3458,11 +3454,6 @@ static int check_sleep(int need_activity, int sleep_now)
     if (needs_sleep_cancelled)
       return 0;
 
-#if defined(UNIX_PROCESSES)
-    if (scheme_check_child_done())
-      return 0;
-# endif
-
     if (post_system_idle()) {
       return 0;
     }
@@ -3859,10 +3850,6 @@ void scheme_thread_block(float sleep_time)
   /* Check scheduled_kills early and often. */
   check_scheduled_kills();
 
-#if defined(UNIX_PROCESSES)
-  scheme_check_child_done();
-#endif
-
   if (!do_atomic && (sleep_end >= 0.0)) {
     double msecs = 0.0;