simple echo server

[Peter Hansen]

Haris Bogdanovic wrote:
> 
> I removed firewall from my computer but I still get "Permission denied"
> message. I'm not really an expert on firewalls so can you tell me some
> things :
> Does firewall works with both sides i.e. will firewall block me from
> sending something from inside of remote host to my localhost ?
> If that's the case how do I lookup for open ports on that remote host
> through which I can send data ?

Haris, the best way to deal with technical problems like this is to
start simple.  Shut off the firewall, turn off anything else that might
interfere, and try the program.  If you get the same error message(*)
you are obviously not dealing with a firewall problem, so you can
cross that off your list and move on to the next potential cause.

You should also simplify the program to the point where "it cannot
possibly fail".  Make it so simple that if it doesn't work, there 
is almost nothing left to blame.  Usually you'll find something 
laughably trivial, some tiny bug, and once you've fixed it and 
proven that was the cause, you can apply the same fix to the full
(unsimplified) program and continue troubleshooting additional
problems.

Two more pieces of advice: 

These are not necessarily Python problems, at least not based on your 
description, so you should be working *very* hard to help those helping 
you, since they are not really here to provide basic PC training or 
troubleshooting for problems unrelated to Python.  The participants in this 
group are quite generous with their time, for the most part, but at 
some point if it becomes clear that you aren't really trying, they'll 
just give up.

Item two, and *this is very important*.  You've been asked before, 
yet still have not acted on this.  You MUST provide the *actual*
error message, cut and pasted, using your mouse, from the window 
where you see it, into the newsgroup posting or email message.  If
you don't do this, but merely type "permission denied" over and
over, nobody will be able to help you.

Python always produces a "traceback" when a program raises an
exception, complete with line numbers and module names, showing the
failing lines in detail.  If there is one, include it.

If this is not a Python traceback, but rather an operating system
error message, cut and paste the actual *command and response* that
you see in your console window.  Include the prompt, include the
previous command, include anything that might help.  If you don't
do this, please don't expect much help since you're forcing everyone
to guess.

-Peter