Re: tcludp - bug when closing 1-of-2 listening ports

On Nov 4, 11:35 am, Vera <vera_s...@xxxxxx> wrote:

The packet "exit" shall simulate an eof on logical layer, because IMHO
udp (other than tcp?) has no eof or other notification, that the sender
closes the sending port.

Correct. EOF is a stream-oriented concept (TCP, pipes, files,
devices). UDP packets are just independent datagrams.

You did observe an empty packet on tcp, too?

No. "Empty" packets do occur in TCP, but they are normal, since they
carry acknowledge and flow control information, and they certainly
don't bubble up to the client program.

Moreover, TCP sockets are built into Tcl, while UDP is in an
extension. Different numbers of users, and of maintainers. That
explains why one is more polished than the other ;-)

Is there an unknown-feature/bug on tcl's close?

The problem is in TclUDP's channeltype-dependent closeProc and
fileevent handling code. Not in the generic channel layer's [close].
That why I keep suggesting you to turn to the author ;-)

-Alex
.

Relevant Pages

  • Re: UPD better than TCP in streaming video/audio ?
    ... > UDP gains speed over TCP because it carries no information that would ... it doesn't even know that packets were lost. ... which is perfect for UDP. ... > Finally, there's the possibility of multicast data - for instance, a live ...
    (microsoft.public.win32.programmer.networks)
  • Re: NTP and Firewall help needed.
    ... >>port 123 for udp and tcp. ... The action here is applied for packets that fall off ... > - ACCEPT any and all traffic coming from the localhost interface ...
    (comp.os.linux.setup)
  • Re: Old SUN NFS performance papers.
    ... > also just generally a good idea, since UDP frags act as a fixed ... > you may be copying all your packets over again ), ... With TCP, you ... >> FreeBSD NFS servers, and therefore always looking for tweaks and nobs ...
    (freebsd-performance)
  • Re: NTP and Firewall help needed.
    ... >port 123 for udp and tcp. ... Also the idea of combining rules for packets arriving at the local machine ... ACCEPT any and all traffic coming from the localhost interface ...
    (comp.os.linux.setup)
  • Re: UDP vs TCP
    ... I understand that UDP doesn't guarantee proper delivery of the message, that's why we have to add the CRC to the message to check if the message received is correct. ... TCP for instance will break up a large packet into smaller ... > into the packets and then the receiving app would have to read ...
    (microsoft.public.vb.enterprise)