issue with SB-BSD-SOCKETS:SOCKET-CLOSE
Reported by Lorenz Mösenlechner:
If the client has already dropped connection:
It first tries to close the stream, without the abort parameter, and invalidates its stream slot in a unwind-protect protection form.
That means the 'broken-pipe' condition will be raised but the stream will stay open and even worse will be not bound to a slot anymore.