My application check /sys/class/net/eth0/carrier for ethernet status;
it works great on RPI 3B but broken on RPI 3B+.
If I plug out the RJ45 cable from both RPI 3B/3B+ :
the RPI 3B will change the carrier status from 1 to 0
but RPI 3B+ won't change anything.
Is there any attribute that my application can check for RPI 3B+ ethernet status?