rs::context set_devices_changed_callback does not always notify of a sensor disconnect

[banuprathap]

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Required Info
Camera Model	D435
Firmware Version	05.12.09.00
Operating System & Version	Ubuntu 14.04
Kernel Version (Linux Only)	4.4
Platform	Intel Com Xpress
SDK Version	2.48.0
Language	C++
Segment	Robot

When use the set_devices_changed_callback to detect device connect and disconnect events. We noticed that this mechanism does not always invoke the registered callback of disconnect events. We have not come across any issue with a subsequent connect. In other words, even if the callback was not invoked for disconnect, it gets invoked when the sensor is connected back.

Is there a recommended way to reliably detect the sensor disconnects?

[MartyG-RealSense]

Hi @banuprathap Did you build the librealsense SDK using the RSUSB backend method or with the kernel patching method, please?

If you are using RSUSB (which is known to have issues with timing when polling) then you could either use a kernel-patched librealsense build instead or reduce the time period between each polling of the device under RSUSB, as described in the comment linked to below and the comments beneath it.

#6921 (comment)

[MartyG-RealSense]

Hi @banuprathap Do you require further assistance with this case, please? Thanks!

[MartyG-RealSense]

Case closed due to no further comments received.