--- a/svghmi/svghmi.py	Fri Jan 10 13:15:07 2020 +0100
+++ b/svghmi/svghmi.py	Fri Jan 10 17:00:01 2020 +0100
@@ -13,6 +13,7 @@
 from pprint import pformat
 import hashlib
 import weakref
+import shlex
 
 import wx
 import wx.dataview as dv
@@ -375,8 +376,9 @@
     <xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema">
       <xsd:element name="SVGHMI">
         <xsd:complexType>
-          <xsd:attribute name="enableHTTP" type="xsd:boolean" use="optional" default="false"/>
-          <xsd:attribute name="bindAddress" type="xsd:string" use="optional" default="localhost"/>
+          <xsd:attribute name="OnStart" type="xsd:string" use="optional"/>
+          <xsd:attribute name="OnStop" type="xsd:string" use="optional"/>
+          <xsd:attribute name="OnWatchdog" type="xsd:string" use="optional"/>
           <xsd:attribute name="port" type="xsd:string" use="optional" default="8080"/>
         </xsd:complexType>
       </xsd:element>
@@ -503,19 +505,37 @@
         target_file.close()
 
         res += ((target_fname, open(target_path, "rb")),)
+        
+        svghmi_cmds = {}
+        for thing in ["Start", "Stop", "Watchdog"]:
+             given_command = self.GetParamsAttributes("SVGHMI.On"+thing)["value"]
+             if given_command:
+                 svghmi_cmds[thing] = shlex.split(given_command)
 
         runtimefile_path = os.path.join(buildpath, "runtime_svghmi1_%s.py" % location_str)
         runtimefile = open(runtimefile_path, 'w')
         runtimefile.write("""
+# TODO : multi        
+svghmi_cmds = %(svghmi_cmds)s
+def svghmi_cmd(cmd):
+    if cmd in svghmi_cmds:
+        Popen(svghmi_cmds[cmd])
+
+def watchdog_trigger():
+    svghmi_cmd("Watchdog")
+
 def _runtime_svghmi1_%(location)s_start():
     svghmi_root.putChild('%(view_name)s',File('%(xhtml)s', defaultType='application/xhtml+xml'))
+    svghmi_cmd("Start")
 
 def _runtime_svghmi1_%(location)s_stop():
     svghmi_root.delEntity('%(view_name)s')
+    svghmi_cmd("Stop")
 
         """ % {"location": location_str,
                "xhtml": target_fname,
-               "view_name": view_name})
+               "view_name": view_name,
+               "svghmi_cmds": repr(svghmi_cmds)})
 
         runtimefile.close()
 

--- a/svghmi/svghmi_server.py	Fri Jan 10 13:15:07 2020 +0100
+++ b/svghmi/svghmi_server.py	Fri Jan 10 17:00:01 2020 +0100
@@ -9,6 +9,11 @@
 import errno
 from threading import RLock, Timer
 
+try:
+    from runtime.spawn_subprocess import Popen
+except ImportError:
+    from subprocess import Popen
+
 from twisted.web.server import Site
 from twisted.web.resource import Resource
 from twisted.internet import reactor

--- a/tests/svghmi/plc.xml	Fri Jan 10 13:15:07 2020 +0100
+++ b/tests/svghmi/plc.xml	Fri Jan 10 17:00:01 2020 +0100
@@ -1,7 +1,7 @@
 <?xml version='1.0' encoding='utf-8'?>
 <project xmlns:ns1="http://www.plcopen.org/xml/tc6_0201" xmlns:xhtml="http://www.w3.org/1999/xhtml" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns="http://www.plcopen.org/xml/tc6_0201">
   <fileHeader companyName="Unknown" productName="Unnamed" productVersion="1" creationDateTime="2019-08-06T14:23:42"/>
-  <contentHeader name="Unnamed" modificationDateTime="2019-11-14T13:42:40">
+  <contentHeader name="Unnamed" modificationDateTime="2020-01-10T16:48:16">
     <coordinateInfo>
       <fbd>
         <scaling x="5" y="5"/>

--- a/tests/svghmi/svghmi_0@svghmi/confnode.xml	Fri Jan 10 13:15:07 2020 +0100
+++ b/tests/svghmi/svghmi_0@svghmi/confnode.xml	Fri Jan 10 17:00:01 2020 +0100
@@ -1,2 +1,2 @@
 <?xml version='1.0' encoding='utf-8'?>
-<SVGHMI xmlns:xsd="http://www.w3.org/2001/XMLSchema"/>
+<SVGHMI xmlns:xsd="http://www.w3.org/2001/XMLSchema" OnWatchdog="echo Banana" OnStart="echo Whaaaa" OnStop="echo Hoooo"/>