java socket problem

[Francois Tigeot]

On Mon, Jan 12, 2015 at 04:07:24PM -0800, javan malachi wrote:
> I was running 4.0.1 and all was well, I jumped over to master a few days
> ago (which fixed my iwn driver reset problem)  However now all java related
> network options just refuse to work.
> Eclipse won't update, gradle can't fetch anything. I tried a few common
> solutions (maybe related with ipv6)
> 
> -Djava.net.preferIPv4Stack=true (doesn't change anything)
> 
> All operations end with
> 
> java.net.SocktException: Operation not supported
> 
> Any clues?

I see the same thing with tomcat6 on -head

ktrace sample:

313643:1    java     CALL  socket(PF_INET6,SOCK_STREAM,0)
313643:1    java     RET   socket 43/0x2b
313643:1    java     CALL  setsockopt(0x2b,0x29,<invalid=27>,0x7fffffbfdcfc,0x4)
313643:1    java     RET   setsockopt -1 errno 45 Operation not supported


I guess this has something to do with the magic IPv4 in an IPv6 socket thing
which was just removed.
Java is known to create IPv6 sockets and try to use IPv4 addresses with them.

A brave soul has written a web page to explain this madness:
http://diario.beerensalat.info/2008/10/12/java_and_ipv6_on_bsd.html

-- 
Francois Tigeot