Great thanks for your reply.
I have no knowledge about what api Steam uses.
I have been played with HIDAPI, Raw input, Windows.gaming.input, but gyro sensor can be detected when only HIDAPI is included.
So far no difference in result on HIDAPI alone or HIDAPI + Raw input , and so on. :(
I wish I could capture gyroscope signal by Raw input alone.
yeah, I have tested while Steam client was off.
Thanks for suggesting SDL3. I will definately look for it. Also at the moment, I might also try USBPcap + Wireshark combination which seems capturing data without HIDAPI, hopefully it's not that difficult, and able to grab.
But apparently your amazing app still helps to solve my interest.
Thanks!