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Date: Thu, 12 Dec 2013 13:27:16 -0800
Subject: Re: [newbie] trying socket as a replacement for nc
From: Dan Stromberg <drsalists@gmail.com>
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On Thu, Dec 12, 2013 at 6:16 AM, Grant Edwards <invalid@invalid.invalid> wrote:

>> Sockets reserve the right to split one socket.send() into multiple
>> socket.recv()'s on the other end of the communication, or to aggregate
>> multiple socket.send()'s into a single socket.recv() - pretty much any way
>> the relevant IP stacks and communications equipment feel like for the sake
>> of performance or reliability.
>
> Just to be pedantic: _TCP_ sockets reserver that right.  UDP sockets
> do not, and do in fact guarantee that each message is discrete.  [It
> appears that the OP is undoubtedly using TCP sockets.]

I haven't done a lot of UDP, but are you pretty sure UDP can't at
least fragment large packets?  What's a router or switch to do if the
Path MTU isn't large enough for an original packet?

http://www.gamedev.net/topic/343577-fragmented-udp-packets/