Clean up error handling in epoll_apply_one_change() a little The old code was more or less: if (op == X && errno == FOO) { ... } else if (op == Y && errno == BAR) { ... } but really we wanted to do a switch (op) to avoid needless checks and branches. This patch leaves the indentation a little weird so as to make it easier to see what changed; the next patch will fix the indentation.