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Create a TCP/IP Connection

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# 1  
Old 05-12-2008
Create a TCP/IP Connection


I am trying to write a script in Perl which will send some data from a UNIX Box to a windows box. I am planning to create a TCP/IP communication port for the same. How do I go about this? Kindly help.

# 2  
Old 05-12-2008
this module would be of help to you: IO::Socket::INET
# 3  
Old 05-12-2008
The perlipc manual page basically has the stuff you need, although you might need to read up on the background info if you don't understand it on the first read; it really assumes you are familiar with basic socket programming. It all seems quite mysterious until you learn to ignore most of the lingo (-: But try the very simplest examples there; they should suffice for your needs.
# 4  
Old 05-12-2008
Can you please one such simple example. The ones I tried dont seem to work.For eg

#!/usr/intel/bin/perl -w
use IO::Socket;
$remote = IO::Socket::INET->new(
Proto => "tcp",
PeerAddr => "localhost",
PeerPort => "daytime(13)",
or die "cannot connect to daytime port at localhost";
while ( <$remote> ) { print }
# 5  
Old 05-12-2008
That one works here, do you get an error message? Maybe your server doesn't run a daytime service on port 13. Mine doesn't, so I get "cannot connect to daytime port", but adapting it to use a port number for which there is a server allows it to work just fine; there is certainly nothing wrong with the code. Changing it to use port 22, for example, it will print the SSH banner from the SSH server (and then nothing, because it obviously doesn't speak that protocol -- that's why they chose daytime, because it uses such a mind-bogglingly stupid, er, I mean, easy-to-understand demo protocol.)

If you don't have previous experience with network protocols, play around with netcat for a while. Maybe it's actually all you will ever need.


vnix$ nc windows 4343
Stuff I type here will be seen by my Windoze box!
Oh my^C

Last edited by era; 05-12-2008 at 03:42 PM.. Reason: Ctrl-C to break out of netcat
# 6  
Old 05-19-2008
Hello guys,

I can't get this to work. Can you please show me an example (or lead me to one) of how I can setup a TCP Port between 2 unix machines. The simplest of examples will help me build on it. Please help.

# 7  
Old 05-19-2008
It doesn't get much simpler than that. If you can't get the traffic to flow, you have a firewall or something in between the endpoints.

Try get it to work just from localhost to localhost on the Unix box for a start. Open two xterms, run nc -l -p 4343 in window 1 and connect to it with nc localhost 4343 from window 2. Now whatever you type into window 2 should appear at the other end in window 1. Press ctrl-C in window 2 to terminate both.

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