In my configuration,
udp sending (netsend -u)  from a linux machine to macOSX machine on a local ethernet network,
I experienced that the  udp connection  closed when trying to send data if the dest port was not reachable on target machine.
Jean-Yves

On 27/03/2019 12:00, pd-dev-request@lists.iem.at wrote:
Message: 2
Date: Tue, 26 Mar 2019 09:52:33 -0700
From: Miller Puckette <msp@ucsd.edu>
To: Dan Wilcox <danomatika@gmail.com>
Cc: Christof Ressi <christof.ressi@gmx.at>, pd-dev
	<pd-dev@lists.iem.at>
Subject: Re: [PD-dev] netsend/netreceive UDP ignore ECONNREFUSED
Message-ID: <20190326165233.GE27681@ucsd.edu>
Content-Type: text/plain; charset=us-ascii

Incidentally, I get the same behavior (send fails if to a nonexistent local
port, but keeps trying if non-local) on linux.

cheers
Miller

On Tue, Mar 26, 2019 at 05:41:58PM +0100, Dan Wilcox wrote:

That's good to know.

I think I have this working. I will do some cleanup and a push, then you can test.


On Mar 26, 2019, at 4:43 AM, Christof Ressi <christof.ressi@gmx.at> wrote:

sorry for spamming the list today. @Dan you have probably read this already: https://stackoverflow.com/questions/41231270/econnrefused-errors-on-udp-sendto

turns out that at least on my system (Windows 7) [netsend -u] only closes the socket when sending to a non-reachable port on *localhost*. sending to any other (existing or non-existing) host won't close the socket. this means that there's even less reason to consider this a feature and I'm not sure if there are really any patches out there which depend on this behaviour.

Christof

--------
Dan Wilcox
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