EVFILT_SYSCOUNT
if (filter < EVFILT_SYSCOUNT) /* it's a system filter */
filter < EVFILT_SYSCOUNT + user_kfilterc)
kfilter = &user_kfilters[filter - EVFILT_SYSCOUNT];
if (user_kfilterc > 0xffffffff - EVFILT_SYSCOUNT) {
kfilter->filter = (kfilter - user_kfilters) + EVFILT_SYSCOUNT;
for (i = 0; i < EVFILT_SYSCOUNT; ++i) {
km.filter = EVFILT_SYSCOUNT;
for (size_t i = 0; i < EVFILT_SYSCOUNT; i++) {