The unreliability of AF_UNIX datagram sockets

[Corinna Vinschen]

On Apr 29 17:05, Corinna Vinschen wrote:
> On Apr 29 10:38, Ken Brown wrote:
> > Sounds great.  Thanks.
> 
> Don't start just yet.
> 
> I'm still not quite sure if that's really the way to go.  As I see it we
> still have something to discuss here.
> 
> For one thing, using native AF_UNIX sockets will split our user base
> into two.  Those who are not using a recent enough Windows will get the
> old code and no descriptor passing.  However, if an application has been
> built with descriptor passing, it won't work for those running older
> Windows versions.  I don't think we want that for the distro, or, do we?
> 
> Next problem... implementing actual STREAM sockets.  Even using native
> AF_UNIX sockets, these, too, would have to encapsulate the actual
> payload because of the ancilliary data we want to send with them.
> Whether or not we use native AF_UNIX sockets, they won't be compatible
> with native applications...

While searching the net I found this additional gem of information: 

Native AF_UNIX sockets don't support abstract sockets.  You must bind to
a valid path, so you always have a visible file in the filesystem.
Discussed here: https://github.com/microsoft/WSL/issues/4240

We could workaround that with our POSIX unlink semantics, probably,
but it's YA downside.


Corinna