see discussion on sctp-dev: http://mail.openjdk.java.net/pipermail/sctp-dev/2010-January/000151.html
Essentially, on Linux SO_SNDBUF/SO_RCVBUF aren't symmetric. This stems from additional socket structures in the send and receive buffers. Net_GetSockOpt handles this by dividing the retrieved values by 2.
CR 6916922: SO_RCVBUF & SO_SNDBUF returns twice the value set Webrev: http://cr.openjdk.java.net/~chegar/6916922/webrev.0/webrev/ -Chris.
