On Tue, 23 Jan 2007 16:44:10 +1100
Herbert Xu <[EMAIL PROTECTED]> wrote:
> dean gaudet <[EMAIL PROTECTED]> wrote:
> > in the test program below the getsockname result on a TCP socket changes
> > across a write which produces EPIPE... here's a fragment of the strace:
> >
> > getsockname(3, {sa_family=AF_INET, sin_port=htons(37636),
> > sin_addr=inet_addr("127.0.0.1")}, [17863593746633850896]) = 0
> > ...
> > write(3, "hi!\n", 4) = 4
> > write(3, "hi!\n", 4) = -1 EPIPE (Broken pipe)
> > --- SIGPIPE (Broken pipe) @ 0 (0) ---
> > getsockname(3, {sa_family=AF_INET, sin_port=htons(59882),
> > sin_addr=inet_addr("127.0.0.1")}, [16927060683038654480]) = 0
> >
> > why does the port# change? this is on 2.6.19.1.
>
> Prior to the last write, the socket entered the CLOSED state meaning
> that the old port is no longer allocated to it. As a result, the
> last write operates on an unconnected socket which causes a new local
> port to be allocated as an autobind. It then fails because the socket
> is still not connected.
Why does write cause an autobind? One would think that on a
SOCK_STREAM socket, the write should just fail with ENOTCONN
>
> So any attempt to run getsockname after an error on the socket is
> simply buggy.
>
> Cheers,
--
Stephen Hemminger <[EMAIL PROTECTED]>
-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at http://vger.kernel.org/majordomo-info.html