[Swan-dev] Question on writefds fd

[Paul Wouters]

On Thu, 15 Jan 2015, D. Hugh Redelmeier wrote:

> | From: Paul Wouters <paul at nohats.ca>
>
> | So only the adns code is using the writefds fd in pluto. Since that code
> | is now being removed and replaced with a libevent variant, there is
> | nothing left in the writefds. Is there any reason to not completely
> | remove it? (I'm a little confused why we had a readfds and writefds)
>
> My understanding is that the ADNS code is being replaced by an unbound
> variant, not a libevent variant.  Unless I misunderstand.

unbound events hooks into libevent.

> If nobody is using writefds, surely it can be removed.  I haven't
> looked at this code in a long time (because it worked).

We justed wanted to make sure there was no design principle behind
writefds (versus readfds) that we were missing.

> I would have thought that we are either 100% libevent or 100% select.
> I don't see how they can be mixed: each needs to be in control.

It's being converted now :)

> Does a set of file descriptors (writefds, readfds) even have any use
> in a libevent world?  Note: I'm asking from ignorance, not knowledge.

No. We were not asking to keep writefds/select, but whether by removing
this now empty fd, we were removing something in the design that we
missed porting. We didn't think so but we wanted to make sure.

Paul