On Thu, May 29, 2008 at 05:40:16PM +0200, Valery Kholodkov wrote: > Greetings! > > Since discovering libevent for myself I've been wondering > why where is still no support for Edge-Triggered behaviour, which > from my point of view could be easily implemented.
Basically, because nobody had written it yet. Thanks for writing it! :) [...] > The patch itself is submitted into SF's patch tracking system: > > http://sourceforge.net/tracker/index.php?func=detail&aid=1968284&group_id=50884&atid=461324 Thanks for reminding me; I've just added a few questions there. > This patch introduces EV_ET flag. Whenever you specify EV_ET in event_set > call a specific module will try enforce Edge-Triggered behaviour. Well, not exactly. The way the patch is written now, when EV_ET is set, *and* you're using the epoll backend or the kqueue backend, you'll get edge-triggered behavior. Otherwise, you get regular behavior. I'm not sure whether this is the right API or not; it might make more sense for event_add to give an error when you try to add an EV_ET event to a backend that doesn't support EV_ET. Alternatively, we could define the semantics of EV_ET so that instead of meaning "make this event edge triggered" it means "make this event edge triggered if possible." (This is one of the comments on the sourceforge patch; I'm hoping we can discuss this more there. Niels: what do you think?) [...] > I hope that maintainers will agree to integrate the patch in future > versions of libevent. I'd definitely like to merge functionality like this into Libevent 2.0. The code looks clear enough, and the functionality certainly seems valuable enough. -- Nick _______________________________________________ Libevent-users mailing list Libevent-users@monkey.org http://monkeymail.org/mailman/listinfo/libevent-users
