PERL sockets

bahadur · 05-07-2005, 11:03 PM

i have this code on the server side

Code:

#!/bin/perl -w
use strict;
use IO::Socket;

		print "Hello welcome to the Fs server\n";
		
		my $sock = new IO::Socket::INET (
		   LocalHost => 'charlie',
		   LocalPort => '7073',
		   Proto => 'tcp',
		   Listen => 1,
		   Reuse => 1,
						);
		die "Could not create socket: $!\n" unless $sock;		
		print " Great just created a socket\n";
		
		my $new_sock = $sock->accept();
				while(defined(<$new_sock>)) {
						print $_;
						}
          
	        close($sock);

and this code on the client side

Code:

#!/bin/perl -w
use strict;
use IO::Socket;


		print " Hello welcome to the fsclient\n";
		
		my $sock = new IO::Socket::INET(
                   PeerAddr => 'charlie',
                   PeerPort => '7073',
                   Proto => 'tcp',
                                  );
		die "Could not create socket: $!\n" unless $sock;
		print $sock "Hello there!\n";
		close($sock);

when i run this server followed by the client this is the error i get

[jnsahibz@charlie assignment2]$ fsserver.pl
Hello welcome to the Fs server
Great just created a socket
Use of uninitialized value at ./fsserver.pl line 19, <GEN1> chunk 1.

Vookimedlo · 05-08-2005, 04:05 AM

just remove defined construction

Code:

#!/bin/perl -w
use strict;
use IO::Socket;

		print "Hello welcome to the Fs server\n";
		
		my $sock = new IO::Socket::INET (
		   LocalHost => 'charlie',
		   LocalPort => '7073',
		   Proto => 'tcp',
		   Listen => 1,
		   Reuse => 1,
						);
		die "Could not create socket: $!\n" unless $sock;		
		print " Great just created a socket\n";
		
		my $new_sock = $sock->accept();
				while(<$new_sock>) {
						print $_;
						}
          
	        close($sock);

bahadur · 05-08-2005, 04:12 AM

thanks a lot it worked.

i was scratching my head on it for the whole day.

i ll be posting more questions on this thread. cause so plz visit this thread when ever i bump it back to the top.

thanks.

bahadur · 05-08-2005, 04:45 AM

and by the way can u explain why this code is working in the first case.

i havent binded it to a address.

i havent used the listen functions either?

every single article i read instructed me to use bind and listen before accepting connections.

so why is this connection working?

as u can see in the code u pasted their is no bind and listen

Code:

#!/bin/perl -w
use strict;
use IO::Socket;

		print "Hello welcome to the Fs server\n";
		
		my $sock = new IO::Socket::INET (
		   LocalHost => 'charlie',
		   LocalPort => '7073',
		   Proto => 'tcp',
		   Listen => 1,
		   Reuse => 1,
						);
		die "Could not create socket: $!\n" unless $sock;		
		print " Great just created a socket\n";
		
		my $new_sock = $sock->accept();
				while(<$new_sock> ) {
						print $_;
						}
          
	        close($sock);

Vookimedlo · 05-08-2005, 05:01 AM

There are two basic ways how you can use sockets.

1) (use Socket;)
Bind and listen are used in low level access.

2) (use IO::Socket;)
Higher level programming with object oriented approach. All bind and listen operation are hidden in the object, so you haven't to call them manually.