Chapman Flack wrote:
>> -.Fn powerhook_establish "void (*fn)(int why, void *a)" "void *arg"
>> +.Fn powerhook_establish "void (*fn)(void *a, int why)" "void *arg"
> 
> I don't suppose there was any practical way to avoid the wholesale
> reversal of argument order? Is that for consistency with the FreeBSD

Oh, here it was in the original message, which escaped my notice:

> and use the eventhandler lists instead, most of the diff is modifying
> the hook functions to reorder their arguments into a standard order.

Was it only powerhooks that needed reversal, while all the other hooks
use a common order that the new powerhook order now conforms to?

How would it be to provide a new function for establishing powerhooks,
deprecate the old one, and provide the old one in a version that simply
enqueues a trivial argument-reversing wrapper for the passed hook
function?

-Chap