[REBOL] Re: retrieving data from TCP port
From: gscottjones:mchsi at: 22-Oct-2002 5:54
Hi, Francois,
From: Francois Prowse
> hmmm, all looks good to me...however
>
> >> result: copy port
> ** Access Error: Network timeout
> ** Where: halt-view
> ** Near: result: copy port
> >>
Bummer.
> I'll have to fire up tcpdump and see if data is
> really comming back in....either that or adjust the
> time outs.
May not be a need to fire up tcpdump nor adjust the time outs. My program
samples suffer from not being able to test a nd adjust. Of course, if you
want to fire up tcpdump, then fire away! :-)
> What does copy wait for before terminating/closing the port
I may not be able to provide the best answer to this question. Basically
copy is waiting for a none to be returned, but in my first example, it tried
to read the response in one chunk, didn't receive the right signal. So copy
stalls on the port. Everything stays open, and finally the network
connection times out. I suspect a tcp/port-ologist could give a much better
answer (in fact my dog on a bad day could probably give a better answer ;-).
What we need is the no-wait refinement and loop that will catch fragments
until the port finally returns a none (I have never figured out how anything
can "receive" a "none"; I guess it is like the sound of one hand clapping.
;-)
Try this variation:
initial: read %initial.xml
port: open/no-wait tcp://x.x.x.x:3221
insert port initial
fragment: copy ""
result: copy ""
while [
wait port
fragment: copy port
] [append result fragment]
close port
either find result "</rpc-reply>" [
print "success!!"
][
print "ooh, got an error..."
]
If that doesn't work, then, yes, I would be happy to try a direct connection
to a machine of your choosing. My guess is that the server might be line
oriented, and that adding a /lines refinement would help. Again, just a
guess...
Good luck!
--Scott Jones
