How to check how many events/callbacks have been queued in Matlab

I have a daq session that runs by startBackground(). It continuously samples analog channels and keeps firing an event and cause a DataAvailable callback whenever sampled data exceeds a pre-set size. However, sometime DataAvailable takes longer to execute, causing the event to be queued up. My question is:

Is there a way to check how many events are queued up?

Thank you!

Answer 1

[Sangeetha Jayaprakash]

It looks like you are trying to check how many scans are still queued after using "startBackground". Try using the functions 'ScansOutputByHardware' and 'ScansAcquired' below:

https://www.mathworks.com/help/daq/ref/scansoutputbyhardware.html

https://www.mathworks.com/help/daq/ref/scansacquired.html

[Tao Cui]

Thanks, what I want to do is more general: for example, I can trigger an event using "notify(h, eventname, eventdata)". Assume there is a listener function added to that event. To my understanding, if that event triggered too fast and too frequently for a short period of time, it will be queued up for the listener function to process in a callback fashion. I am asking, is there a way to check how many event has been queued up for the listener to process?