[baskerville]

Originally Posted by NiLuJe

I was under the impression only the ioctl return value was effectively checked, since rotation() only pulls the "cached" rotate value, it doesn't do a new GET.

The ioctl call mutates self.var_info.

I've attached a test binary that takes a different approach: if writing n fails, then I write (n+1)%4 and finally n.