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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Hello,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I posted about this issue a week ago, and Ian was kind enough to explain this to me. Search the maillist for “Managed ESL: AccessViolationException”.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>In short, yes, accessing the same eslConnection from multiple threads causes this exception. I created a single object which listens for all the events and sends them to all other objects which subscribe to receive events.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>This way you have only 1 thread listening for events on the socket, and can have multiple threads processing the events.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I believe you can send and receive on the same socket from 1 thread, since .net sockets are bi-directional.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> freeswitch-users-bounces@lists.freeswitch.org [mailto:freeswitch-users-bounces@lists.freeswitch.org] <b>On Behalf Of </b>Ferenc Sárközy<br><b>Sent:</b> Thursday, May 29, 2014 4:40 PM<br><b>To:</b> FreeSWITCH Users Help<br><b>Subject:</b> [Freeswitch-users] ESL C# Accessviolation<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hi,<o:p></o:p></p><div><p class=MsoNormal>My C# app uses ESL to interact with FS. It plays wav files via bgapi and receives and processes the events of the playbacks. The listening thread is started like ManagedESLTest program:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>ThreadPool.QueueUserWorkItem(new WaitCallback(getFsEventsInboundMode));<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>this thread ends up in a while loop where the events are received:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><div><p class=MsoNormal> while (eslConnection.Connected() == ESL_SUCCESS && !stopConnection)<o:p></o:p></p></div><div><p class=MsoNormal> {<o:p></o:p></p></div><div><p class=MsoNormal> eslEvent = eslConnection.RecvEventTimed(50); <o:p></o:p></p></div><div><p class=MsoNormal> if (eslEvent != null)<o:p></o:p></p></div><div><p class=MsoNormal> {<o:p></o:p></p></div><div><p class=MsoNormal> onFreeswitcEvent(eslEvent );<o:p></o:p></p></div><div><p class=MsoNormal> }<o:p></o:p></p></div><div><p class=MsoNormal> }<o:p></o:p></p></div></div><div><p class=MsoNormal>onFreeSwitchEvent calls ends up in an other thread.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>bgapi commands is sent via the same eslConnection, I assume that the occasional Accessviolation at RecvEventTimed is caused by sending bgapi commands via the same eslConnection from an other thread. Could that be the cause?<o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Other related questions:<o:p></o:p></p></div><div><p class=MsoNormal>Is it safe to pass eslEvent to an other thread, or it should be serialized? If so is there a best practice to serialize?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Is there some kind of event buffer in eslConnection, or the RecvEvent misses all the events which "arrived" before the call?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Thank you in advance:<o:p></o:p></p></div><div><p class=MsoNormal>Ferenc<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></div></body></html>