From: Joel VanderWerf <vjoel@...>
Date: 2007-09-05T08:05:41+09:00
Subject: Re: Socket send functions only allow you to send strings?

Ryan Parmeter wrote:
> I am writing a small TimeP (RFC 868) server to sync time with some
> networking equipment.  The equipment that shall go nameless requires the
> use of UDP.
> 
> As far as I can tell, my only option to write to a UDPSocket is to use
> the send method, which takes a string.  I need to send a 32bit integer
> representing the date in a UDP packet and I'd love to use something
> like:
> 
> myUDPsocket.send( Time.now.to_i, 0, host, port)
> 
> In my situation I can't change the receiving program to accept a string
> or I could do it that way. I can't convert the integer to a string
> either because that would blow my 32 bit requirement.  Does anyone have
> any idea?

Strings are just blobs of binary data, when they go through #send. The 
receiver doesn't know it started life as a ruby string.

If you want structure, use #pack. You'll need to know what byte-order 
the client and server should use to communicate. Assuming big-endian:

myUDPsocket.send([Time.now.to_i].pack("N"), 0, host, port)

-- 
       vjoel : Joel VanderWerf : path berkeley edu : 510 665 3407