Re: UDP recvmsg blocks after select(), 2.6 bug?

From: Mark Mielke
Date: Sat Oct 16 2004 - 08:28:22 EST


On Sat, Oct 16, 2004 at 12:24:33PM +0200, Willy Tarreau wrote:
> On Fri, Oct 15, 2004 at 03:42:55PM -0700, Robert White wrote:
> > > As I asked in a previous mail in this overly long thread, why not
> > > returning zero bytes at all. It is perfectly valid to receive an
> > > UDP packet with 0
> > Zero bytes is "end of file". Don't go trying to co-opt end of file.
> > That way lies madness and despair.
> Please explain me what "end of file" means with UDP. If your UDP-based app
> expects to receive a zero when the other end stops transmitting, then it
> might wait for a very long time. As opposed to TCP, there's no FIN control
> flag to tell the remote host that you sent your last packet.

He means zero byte packet. :-)

mark

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