From: Eliezer Croitoru <eliezer@...>
Date: 2012-07-10T01:53:01+09:00
Subject: sock.setsockopt how?

i want to use specific tcp\dup socketopts.
in my case i want to use IP_TRANSPARENT SOCKET.
this is the page of tproxy documentation:
http://www.mjmwired.net/kernel/Documentation/networking/tproxy.txt

the option in the kernel ic constant number 19.

i have seen some examples on with setsockopt like this 
http://pastie.org/314914 or the code in bottom.
but i am unable to understand how am i suppose to set the constant?
i have looked at the ruby source code and didnt found anywhere the word 
IP_TRANSPARENT so i suppose it wasnt integrated into the source.
any suggestions?

Thanks,
Eliezer

require 'socket'

opt = [1, 500_000].pack("I_2")

sock = Socket.new(Socket::AF_INET, Socket::SOCK_STREAM, 0)
sockaddr = Socket.pack_sockaddr_in(3232, '192.168.1.10')

sock.setsockopt(Socket::SOL_SOCKET, Socket::SO_RCVTIMEO, opt)
puts "sockopt = #{sock.getsockopt(Socket::SOL_SOCKET,
Socket::SO_RCVTIMEO).inspect}"

sock.connect(sockaddr)

#this tells the server at 192.168.1.10:3232 to wait 10 seconds before
responding, so we should get a timeout on our socket
sock.write("10\r\n")

start_time = Time.now
result = sock.gets
time = Time.now - start_time

puts "read: #{sock.gets} after: #{time} seconds"
#no timeout occured, this read returns after 10 seconds




-- 
Eliezer Croitoru
https://www1.ngtech.co.il
IT consulting for Nonprofit organizations
eliezer <at> ngtech.co.il