Re: [BEHAVE] (no subject)

Simon Perreault <simon.perreault@viagenie.ca> Thu, 27 June 2013 05:45 UTC

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Date: Thu, 27 Jun 2013 07:45:44 +0200
From: Simon Perreault <simon.perreault@viagenie.ca>
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Subject: Re: [BEHAVE] (no subject)
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Le 2013-06-26 15:51, ivan c a écrit :
>>> We have, for all UDP communications and all outbound TCP sessions:
>>> - one socket is bound to one local endpoint on the host. Additionally,
>>> two sockets have to bind to two different local endpoints.
>>
>> Not true. If you call connect() on a UDP socket, it behaves just like a
>> TCP socket.
>
> "Not true". interesting...
> Do you mind providing a counterexample, ie some pseudo-code that binds two
> sockets of the same protocol to the same local endpoint?

s1 = socket(..., SOCK_DGRAM, ...);
s2 = socket(..., SOCK_DGRAM, ...);
connect(s1, ...);
connect(s2, ...);

The kernel is free to use the same local endpoint for those two sockets 
as long as the remote endpoint is different.

If you really want to force reusing the same local endpoint, you do the 
SO_REUSEADDR+bind() dance before calling connect().

Simon
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