Re: Question on select() and sockets

David Schwartz <davids@xxxxxxxxxxxxx> writes:
On Jun 13, 2:47 am, Rainer Weikusat <rweiku...@xxxxxxxxxxx> wrote:
David Schwartz <dav...@xxxxxxxxxxxxx> writes:
On Jun 11, 4:15 am, Rainer Weikusat <rweiku...@xxxxxxxxxxx> wrote:
The only 'relevant standards' here would be RFC768 ('user datagram
protocol') and RFC791 ('internet protocol'). Neither of both prohibits
cannibalism. Hence, anyone coming too close to a UDP implementation
runs the very real danger of being eaten by it.

Actually, no, since the semantics of things like 'select' and
'recvmsg' are specified by POSIX.

You were refering to an 'UDP standard', and that's what I was writing
about.

But I never claimed that was the only relevant standard. That was your
claim, and it's false.

| You were refering to an 'UDP standard', and that's what I was writing
| about.

In particular, the 'only relevant standards' was meant to only refer
to UDP.

[...]

If you mean dropping a datagram, this should
never be any kind of big deal. One of IP's main points is that
implementations are free to drop datagrams,

That's one of your ideas about IP-implementations.

If you're going to resort to "that's what you think", don't bother
replying. If you have some kind of actual response to that, go for
it.

I already posted all the 'actual responses', including quoting a part
of the IP-RFC. Actually, my sentence above is such an 'actual
response', too: The behaviour you were writing about is not specified
by these RFCs, which describe the respective protocols and the
services offered (or not offered) by them. Starting from the protocol
behaviour, you came to the conclusion that 'a UDP-implementation may
elect to be as useless as technically possible, eg by randomly
dropping data it has already received'. But the only applicable thing
which is actually defined in the standard regarding this is that the
UDP- and IP-protocol modules provide no help to an applications which
would need to deal with an implementation behaving in this way.

.

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