One-shot semantics in GHC event manager

[Kazu Yamamoto (=?iso-2022-jp?B?GyRCOzNLXE9CSScbKEI=?=)]

>> Q: Since registerFd uses OneShot and threadWait uses registerFd, basic
>>    IO functions use OneShot by default. No changes from GHC 7.8.3. Do
>>    I understand correctly?
>>
> That is the idea. That being said adding another variant of registerFd
> (which as far as I know has three users) for backwards compatibility
> seems a bit silly. If we decided to punt on this patch until 7.10 I'd
> say we should just change the interface of registerFd. If we are going
> to put it in 7.8.4, however, then this isn't as clear.

Understood. Thanks.

>> Q: dbus library will use registerFd' to specify MultiShot, right?
>>
> I'm not sure about dbus but this is how usb will use it, yes. Does dbus
> also use the event manager directly?

Never mind. I meant usb, not dbus.

--Kazu