[jeffbee]

Right, doing interfaces that support DI would also force Linux to grow up and learn how to build and ship a peak-optimized artifact with de-virtualization and post-link optimization and all the goodies. It would be a huge win for users.

The fact that it would be hard to test certain edge cases does not in any way excuse the fact that the overwhelming bulk of functions in Linux are pure functions that are thread-hostile anyway, and these all need tests. The hard cases can be left for last.