Meaning of SOAPY_SDR_TIME_ERROR in readStreamStatus()

[schneider42]

I'm currently working with a LimeSDR and noticed that it is dropping samples, but gr-soapy is not reporting that.

Further investigation showed that in my case it was dropping samples inside the driver where USB transfers are handled. SoapyLMS7 does report that via readStreamStatus(): https://github.com/myriadrf/LimeSuite/blob/master/SoapyLMS7/Streaming.cpp#L503

My goal is to extend gr-soapy to at least print a warning when this happens. Now I'm wondering: what is the exact meaning of SOAPY_SDR_TIME_ERROR?

• On the lime it indicated dropped samples (specifically missed USB transfers).
• In the UHD implementation it maps to EVENT_CODE_TIME_ERROR (https://files.ettus.com/manual_archive/v3.11.0.1/html/structuhd_1_1async__metadata__t.html#a2be1b5c0351746c78fa3bcb74a8ff5daa7bfefebda6f394356f08f067d2752357).
• The bladeRF driver does something else yet: https://github.com/pothosware/SoapyBladeRF/blob/master/bladeRF_Streaming.cpp#L553

Is it possible that the SoapyLMS7 makes use of the flag in an unexpected way? Should this flag generally be treated as an indication of "lost samples"?