Re: Socket doesn't get EOF

[carlsonj@workingcode.com]

K-sPecial writes:
> Hey, i've got an irc bot of over 3000 lines of perl. I test for EOF on 
> occasion and do a reconnect if eof is detected. This works greatly for 
> instances as when the socket times out or is disconnected in most 
> manors. It doesn't although register an eof when pppd dies. I realy 
> don't know if this might be specific to perl or if even in C this is an 
> issue.

This is a frequently-asked question about TCP/IP.

No, you won't get EOF.  No, it's not a bug.  It's a feature, and it's
by design.  The TCP layer sees IP as a connectionless datagram
service, and tries its best to deliver the data the application
provides.  IP sees the datalink layers as unrelated to any particular
transport, so when a datalink layer goes down, the transport (such as
TCP) isn't involved.  If IP can route around the problem, it does so.
If it can't, it drops the packets and hopes that either (A) the link
comes back 'soon' or (B) the transport gives up eventually.

If you want a shorter timeout, set a timer in your application.

-- 
James Carlson                                 <carlsonj@workingcode.com>