1 files changed, 5 insertions, 29 deletions
diff --git a/nuttx/sched/task_vfork.c b/nuttx/sched/task_vfork.c
index 7008a016e..58b4152ed 100644
--- a/nuttx/sched/task_vfork.c
+++ b/nuttx/sched/task_vfork.c
@@ -54,6 +54,9 @@
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
+/* vfork() requires architecture-specific support as well as waipid(). */
+
+#if defined(CONFIG_ARCH_HAVE_VFORK) && defined(CONFIG_SCHED_WAITPID)
 
 /****************************************************************************
  * Private Functions
@@ -220,9 +223,7 @@ pid_t task_vforkstart(FAR struct task_tcb_s *child)
 #endif
   FAR const char *name;
   pid_t pid;
-#ifdef CONFIG_SCHED_WAITPID
   int rc;
-#endif
   int ret;
 
   svdbg("Starting Child TCB=%p, parent=%p\n", child, g_readytorun.head);
@@ -279,8 +280,6 @@ pid_t task_vforkstart(FAR struct task_tcb_s *child)
    * after the parent thread again?
    */
 
-#ifdef CONFIG_SCHED_WAITPID
-
   /* We can also exploit a bug in the execv() implementation:  The PID
    * of the task exec'ed by the child will not be the same as the PID of
    * the child task.  Therefore, waitpid() on the child task's PID will
@@ -299,31 +298,6 @@ pid_t task_vforkstart(FAR struct task_tcb_s *child)
   (void)waitpid(pid, &rc, 0);
 #endif
 
-#else
-  /* The following logic does not appear to work... It gets stuff in an
-   * infinite kill() loop and hogs the processor.  Therefore, it looks
-   * as though CONFIG_SCHED_WAITPID may be a requirement to used vfork().
-   *
-   * Again exploiting that execv() bug: Check if the child thread is
-   * still running.
-   */
-
-  while (kill(pid, 0) == OK)
-    {
-      /* Yes.. then we can yield to it -- assuming that it has not lowered
-       * its priority.  sleep(0) might be a safer thing to do since it does
-       * not depend on prioirities:  It will halt the parent thread for one
-       * system clock tick.  This will delay the return to the parent thread.
-       */
-
-#ifndef CONFIG_DISABLE_SIGNALS
-      sleep(0);
-#else
-      sched_yield();
-#endif
-    }
-#endif
-
   return pid;
 }
 
@@ -349,3 +323,5 @@ void task_vforkabort(FAR struct task_tcb_s *child, int errcode)
   sched_releasetcb((FAR struct tcb_s *)child);
   set_errno(errcode);
 }
+
+#endif /* CONFIG_ARCH_HAVE_VFORK && CONFIG_SCHED_WAITPID */