Socket usage in PlainSocketImpl.initProto()

[Jeffrey Sinclair]

hotspot-dev,

I've been looking at the lsof output of my hotspot process and noticed
the following:

java    14429 jeffsinc    8r  sock     0,4             3932632 can't
identify protocol

The above appears on the first ServerSocket that is ever opened and
remains after all ServerSockets have been closed. After a little
investigation I've found that the socket is opened in the initialization
of the PlainSocketImpl class, specifically in the native initProto()
method.

I'm curious to know what is done in the network stack initialization
phase that requires a socket to be opened as well as for the socket to
remain open thereafter.

Jeff