[Boost-users] Linux TCP session stays ESTABLISHED when interface is removed

Subject: [Boost-users] Linux TCP session stays ESTABLISHED when interface is removed
From: Chris Verges (cverges_at_[hidden])
Date: 2013-09-25 17:36:42

Hi all,

I'm experiencing an odd phenomenon when using Boost ASIO 1.46.1.  (I know
it's older, but this was inherited.)

Under normal operation, everything is fine.  I can create a TCP server
socket, listen, and accept as expected.  If I disconnect the TCP client
gracefully, everything resets as expected.

However, if I physically remove the network interface -- such as yanking
the USB adapter out of its socket -- the TCP session stills reports as
ESTABLISHED via netstat and the application receives no read error.

I'm at a bit of a loss how this is possible when the underlying OS shows
that the interface no longer exists yet the socket is blocking away
happily.  Has anyone else experienced similar symptoms?  Any advice?

Thanks in advance,
Chris