diff --git a/lib/libc/sys/kqueue.2 b/lib/libc/sys/kqueue.2 index 72b3e544391c..f80c89f75d78 100644 --- a/lib/libc/sys/kqueue.2 +++ b/lib/libc/sys/kqueue.2 @@ -267,16 +267,17 @@ Causes .Fn kevent to leave unchanged any .Fa udata -associated with an existing event. This allows other aspects of the -event to be modified without requiring the caller to know the +associated with an existing event. +This allows other aspects of the event to be modified without requiring the +caller to know the .Fa udata value presently associated. This is especially useful with .Dv NOTE_TRIGGER or flags like -.Dv EV_ENABLE. +.Dv EV_ENABLE . This flag may not be used with -.Dv EV_ADD. +.Dv EV_ADD . .El .Pp The predefined system filters are listed below.