Re: defying original 4.3BSD sockets constraint

On Sat, Apr 18, 2026 at 08:35:58AM +0200, Michael Tuexen wrote:
M> > https://reviews.freebsd.org/D56489
M> > 
M> > I've been thinking of this for almost a week already and I don't see any cons.
M> > Pros are listed in the review - clean way to improve parallelism of connect(2).
M> > Maybe I am missing something?  Decided to post for a wider audience than just
M> > the reviews.f.o.  Please speak up if you think I am missing something!
M> I think the sequence of bind() operations is not important.
M> 
M> If I understand you correctly, you say bind(specific) after bind(wildcard)
M> is bad, since the instance of bind(specific) is stealing packets.
M> 
M> The same applies (in my view) for bind(wildcard) after bind(specific).
M> If bind(wildcard) succeeds, the caller assumes that it gets all packets,
M> but that is not true.
M> 
M> The only difference is when the "stealer" took action.

I see your point.  With current code the victim would get EADDRINUSE and thus
will learn that a stealer exists.  With my change that would not happen.  Of
course 99% of software set SO_REUSEADDR and thus bypass this check.

-- 
Gleb Smirnoff