Unix domain datagram based messaging

[Volker Lendecke]

On Thu, Apr 10, 2014 at 12:02:13PM -0700, Jeremy Allison wrote:
> On Thu, Apr 10, 2014 at 08:46:58PM +0200, Volker Lendecke wrote:
> > On Thu, Apr 10, 2014 at 10:05:31AM -0700, Jeremy Allison wrote:
> > > In fact the only thing I can see that
> > > might be an issue here is how does
> > > unix_dgram_recv_handler() handle
> > > a it if we get a geniune error that
> > > causes recv() to return -1. Won't it
> > > keep getting called ? I'll do some
> > > more digging here..
> > 
> > Yep, that's what I thought as well. ENOMEM is one that might
> > hit us like the Solaris socket problem, but there retry
> > should not hurt and might be the right thing. The only thing
> > I can really imagine to happen here is that someone else
> > closes the socket behind our back, but then we deserve a
> > 100% loop, right? :-)
> 
> Errr, well - maybe :-). Can't you have
> the struct poll_watch->callback return
> an int to tevent_watch_handler(), and
> have it remove the fde if it comes
> back with -1 ? That at least would
> protect us from horrible CPU loops :-).

Question: Why would the event loop call a handler on this
kind of error? I can see the 100% loop in poll itself, but
do we call the callback if we just see POLLERR or the epoll
equivalent?

Volker

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