Different error on socket while connecting to a box behind firewall

Corinna Vinschen corinna-cygwin@cygwin.com
Thu Sep 8 13:49:00 GMT 2011

On Sep  5 08:08, Andrey Repin wrote:
> > However, even with this fix, you might not get EHOSTUNREACH either.  In
> > my testing, the error returned by the underlying Winsock getsockopt
> > function is not WSAEHOSTUNREACH, but WSAETIMEDOUT.  This will be
> > translated into ETIMEDOUT == "Connection timed out".
> To clarify, and what I think is important to understand, is that the "Host
> unreachable" error status could only be triggered by the parent router
> returning an explicit "not reachable" reply to a connection attempt. But since
> this reply is an ICMP message, many poorly configured intermediate routers,
> like home firewalls, could block it and you will get the WSATIMEDOUT for no
> apparent answer from the remote host in time.

This was a pure local test, trying to connect to an unused port on a
Linux machine.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
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