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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-GB">In the liveMedia FAQ section it is written:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">“(Note that "triggerEvent()" is the only LIVE555 function that may be called from an external (i.e., non-LIVE555) thread.)”.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">We use this possibility and trigger an event from a non-LIVE555 thread. Sometimes an the event “disappears” ie. it is signalled using triggerEvent() but the eventHandler is not called. The LIVE555 changelog has the following
entry:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:DA">2015.03.16:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:DA">- Made a small change to the "BasicTaskScheduler" implementation to reduce the likelihood of<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:10.0pt;font-family:"Courier New";color:black;mso-fareast-language:DA"> a race condition with external thread(s) calling "triggerEvent()".<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Is it correct that there is a non-zero possibility, that the event will disappear due to the variables BasicTaskScheduler0::fTriggersAwaitingHandling and BasicTaskScheduler0::fTriggeredEventClientDatas being accessed
concurrently by the LIVE555 thread and a non-LIVE555 thread?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">The behaviour is not immediately obvious from the FAQ and the function description, but we think it is what we “see” and a workaround to re-trigger the event at a later time seems to work for now.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Do you also see an issue here?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> virtual void triggerEvent(EventTriggerId eventTriggerId, void* clientData = NULL) = 0;<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // Causes the (previously-registered) handler function for the specified event to be handled (from the event loop).<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // The handler function is called with "clientData" as parameter.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // Note: This function (unlike other library functions) may be called from an external thread<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // - to signal an external event. (However, "triggerEvent()" should not be called with the<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> // same 'event trigger id' from different threads.)<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D;mso-fareast-language:DA">Best Regards<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span lang="EN-GB" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:#1F497D;mso-fareast-language:DA">Jan Rørgaard Hansen<o:p></o:p></span></b></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">Lead Software Developer</span><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D;mso-fareast-language:DA"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-AU" style="font-size:8.0pt;font-family:"Arial",sans-serif;mso-fareast-language:DA">Communication Solutions<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-AU" style="font-size:8.0pt;font-family:"Arial",sans-serif;mso-fareast-language:DA">Business Area Surveillance<i><o:p></o:p></i></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">Tel.: + 45 3638 3000<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-GB" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:#1F497D;mso-fareast-language:EN-GB">Call me on:
<a href="skype:jan.r.hansen@dk.saabgroup.com?call"><span style="color:blue">Skype</span></a></span><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">E-mail:
</span><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;mso-fareast-language:DA"><a href="mailto:jan.r.hansen@dk.saabgroup.com"><span style="color:blue">jan.r.hansen@dk.saabgroup.com</span></a><span style="color:black"><o:p></o:p></span></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span style="mso-fareast-language:DA"><img border="0" width="113" height="36" style="width:1.175in;height:.375in" id="Picture_x0020_1" src="cid:image001.jpg@01D993CF.50665F60" alt="Saab_rgb_150px"></span><span lang="EN-US" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span style="font-size:9.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">Saab Danmark A/S<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">Porten 6<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">DK – 6400 Sonderborg
<o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span style="mso-fareast-language:DA"><a href="http://www.saabgroup.com/"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:blue">www.saabgroup.com</span></a></span><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p></o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA"><o:p> </o:p></span></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><i><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">This e-mail is private and confidential between the sender and the addressee.
<o:p></o:p></span></i></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><i><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">In the event of misdirection, the recipient is prohibited from using, copying
or <o:p></o:p></span></i></p>
<p class="MsoNormal" style="line-height:12.0pt;text-autospace:none"><i><span lang="EN-US" style="font-size:8.0pt;font-family:"Arial",sans-serif;color:black;mso-fareast-language:DA">disseminating it or information in it. Please notify the above if any misdirection.<o:p></o:p></span></i></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
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