How implementation details become ABI: a case study

Whoever it had been, the whole point is that this ship has long sailed. Perhaps the main lesson is that single-use APIs tend to suck. "It's just for fuser and lsof" should've been a major red flag. For _those_ this (deleted) thing was probably more convenient - no need to do anything with the string on the userland side. And it wouldn't be a problem, except that there's no miracles and it *had* gained other users. Worse, now we can't change it without breaking existing userland, as this story has demonstrated.