--- plugin/down-root/down-root.c.orig	2009-12-11 00:35:04.000000000 +0100
+++ plugin/down-root/down-root.c	2010-08-16 13:44:45.754293154 +0200
@@ -44,12 +44,14 @@
 /* Command codes for foreground -> background communication */
 #define COMMAND_RUN_SCRIPT 0
 #define COMMAND_EXIT       1
+#define COMMAND_PING       2
 
 /* Response codes for background -> foreground communication */
 #define RESPONSE_INIT_SUCCEEDED   10
 #define RESPONSE_INIT_FAILED      11
 #define RESPONSE_SCRIPT_SUCCEEDED 12
 #define RESPONSE_SCRIPT_FAILED    13
+#define RESPONSE_PING_REQUEST     14
 
 /* Background process function */
 static void down_root_server (const int fd, char *command, const char *argv[], const char *envp[], const int verb);
@@ -388,6 +390,28 @@
 	  return 0; /* NOTREACHED */
 	}
     }
+  else if (type == OPENVPN_PLUGIN_UP && context->foreground_fd >= 0) /* no need to fork a second process */
+    {
+
+      /* Check process communication */      
+
+      if (send_control (context->foreground_fd, COMMAND_PING) == -1)
+	{
+	  fprintf (stderr, "DOWN-ROOT: Error sending ping request signal to background process\n");
+	}
+      else
+	{
+	  const int status = recv_control (context->foreground_fd);
+	  if (status == RESPONSE_PING_REQUEST) 
+	    {
+	      return OPENVPN_PLUGIN_FUNC_SUCCESS;
+	    }
+	  else
+	    {
+	      fprintf (stderr, "DOWN-ROOT: Error receiving ping reception confirmation from background process\n");
+	    }
+	}
+    }
   else if (type == OPENVPN_PLUGIN_DOWN && context->foreground_fd >= 0)
     {
       if (send_control (context->foreground_fd, COMMAND_RUN_SCRIPT) == -1)
@@ -527,6 +551,15 @@
 	    }
 	  break;
 
+	case COMMAND_PING: /* allows to check if process is listening */
+
+	  if (send_control (fd, RESPONSE_PING_REQUEST) == -1)
+	    {
+	      fprintf (stderr, "DOWN-ROOT: BACKGROUND: write error on response socket [4]\n");
+	      goto done;
+	    }
+	  break;
+
 	case COMMAND_EXIT:
 	  goto done;