From: "Iñaki Baz Castillo" <ibc@...>
Date: 2010-01-12T22:32:24+09:00
Subject: Re: How to close a TCP socket? (TCPSocket#close doesn't close it)

El Martes, 12 de Enero de 2010, Brian Candler escribió:

> When I run this code, substituting a 'www.google.com' and port 80, I see
> the socket in TIME_WAIT state if I go to another terminal.
> 
> This is with
> ruby 1.8.6 (2007-09-24 patchlevel 111) [i486-linux]
> built from source, running under Ubuntu Hardy.
> 
> It appears to be consistent: i.e. I can ctrl-C out of the program and
> start it again, and each time I get another TIME_WAIT socket.

I really sorry, I was doing a "grep ESTABLISHED" in my netstat command...
Of course the TIME_WAIT appears after closing the connection :)
Sorry.


 
> Whilst what you're doing is probably allowed, it's a bit ugly: one
> thread is waiting to read data from a socket at the same time as another
> closes it.
> 
> There is a more graceful way which might be useful. In the writing
> thread you can half-close the socket (@socket.close_write). If the other
> side notices this and then closes from its side, you can then finish
> reading what it sends you and  close the read side.
> 
>   require "socket"
>   @socket = TCPSocket.new('smtp.example.com', 25)
> 
>   Thread.new do
>     while res = @socket.gets("\r\n")
>       STDERR.puts res
>     end
>     @socket.close_read
>   end
> 
>   @socket.close_write
>   sleep 120

Yes, this works much better :)
Thanks a lot.


-- 
Iñaki Baz Castillo <ibc@aliax.net>