I recently ran into a situation where I need to have many many raspberry pi's running all over the country and I need to "talk" to them from a central computer to tell them when to run a particular program I have pre-loaded on them. However the people that will be "hosting" them if you will are very very NON-computer savvy people, so I really can't have them configure their routers to set up VNC or the like connections, so I thought, I can solve this with "Sockets" right? :-) So what I want to do is have the pi's talk to my computer and say "I'm on and running, what do you want me to do?" and then I can send back to them what to do. Problem is I can't get the dang things to connect. :-( I have my router set to forward port 7777 to my computer and I have a no-ip service that hosts a name for my router.

But every time the connection times out and won't connect . What am I doing wrong? Here is my code:

Server Code

use IO::Socket::INET;
 
# auto-flush on socket
$| = 1;
 
# creating a listening socket
my $socket = new IO::Socket::INET (
    LocalHost => '127.0.0.1',
    LocalPort => '7777',
    Proto => 'tcp',
    Listen => 5,
    Reuse => 1
);
die "cannot create socket $!\n" unless $socket;
print "server waiting for client connection on port 7777\n";
 
while(1)
{
    # waiting for a new client connection
    my $client_socket = $socket->accept();
 
    # get information about a newly connected client
    my $client_address = $client_socket->peerhost();
    my $client_port = $client_socket->peerport();
    print "connection from $client_address:$client_port\n";
 
    # read up to 1024 characters from the connected client
    my $data = "";
    $client_socket->recv($data, 1024);
    print "received data: $data\n";
 
    # write response data to the connected client
    $data = "ok";
    $client_socket->send($data);
 
    # notify client that response has been sent
    shutdown($client_socket, 1);
}
 
$socket->close();
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Client Code

#!/usr/bin/perl

use IO::Socket::INET;


$| = 1;

my $socket = new IO::Socket::INET (
PeerHost => 'theaddressofmycomputer.com',
PeerPort => '7777',
Proto    => 'tcp',
);
die "Cannot connect to the server $!\n" unless $socket;
print "Connected to the server!\n";

my $req = "Hello World\n";
my $size = $socket->send($req);
print "Sent data of length $size\n";

shutdown($socket, 1);

my $response = "";
$socket->recv($response, 1024);
print "Recieved response: $response\n";

$socket->close();
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OK, I got it working, thank you to everyone for all your help, it was the windows firewall. I simply had to create an inbound and outbound rule allowing communication on the port I want and it worked like a charm!

I am NOT new to Perl but I am VERY new to "forking" or "threading". What I am trying to do is have a certain number of processes running continuously and when one finishes another one takes it's place... I almost had it this morning then after trying SO MANY different things, I can't even find the original code!! ARG.... But it's driving me crazy.. I know I am so close...

So let's say I have 33 clients, and I want to process 10 of them at a time, I open one then the next, etc until I reach 10, then I want to wait until "any" one of those ten is finished, then start client 11, and so on so forth...

#!/usr/bin/perl

use feature qw/say/;


my $count = 1;

CLIENT:
for my $i (1..33){
  
  if ( $count > 10 ) {
    
    say "waiting for open process";
    while (1) {
      
      if ( wait() ){
        $count = 1;
        redo CLIENT;
      }
    }
  }
  else{
    
    # Stagger the initiating to help CPU
    sleep(5);
  }
  
  $count++ and next if( my $pid = fork() );
  
  unless( $pid ){
    
  say "Processing client $i process count $count";
  # Emulate the time it would take to process..
  sleep(60);
  
  exit;
    
  }
}
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Processing client 1 process count 1
Processing client 2 process count 2
waiting for open process
Processing client 3 process count 3
Processing client 4 process count 4
Processing client 5 process count 5
Processing client 6 process count 6
Processing client 7 process count 7
Processing client 8 process count 8
Processing client 9 process count 9
Processing client 10 process count 10
waiting for open process
Processing client 11 process count 1
Processing client 12 process count 2
Processing client 13 process count 3
Processing client 14 process count 4
Processing client 15 process count 5
Processing client 16 process count 6
Processing client 17 process count 7
Processing client 18 process count 8
Processing client 19 process count 9
waiting for open process
Processing client 20 process count 10
Processing client 21 process count 1
Processing client 22 process count 2
Processing client 23 process count 3
Processing client 24 process count 4
Processing client 25 process count 5
Processing client 26 process count 6
Processing client 27 process count 7
Processing client 28 process count 8
Processing client 29 process count 9
Processing client 30 process count 10
Processing client 31 process count 1
Processing client 32 process count 2
Processing client 33 process count 3
[download]

What's going on here?

What am I missing?

I've also tried implementing it with Parallel:ForkManager and Thread::Queue ... Just seems that I'm missing something very simple yet elementary.

Any help would be greatly appreciated!! All I doing now is opening 10 clients and waiting an hour to open the next set using:

In a loop, but it's wasting SO MUCH time, I think I could increase my productivity by 2-3 fold if I could maintain a constant number of processes...

I humbly pray for the wisdom of the Monks...

open (FIL, "+<stuff.txt") or die "$!";
 
foreach $line (<FIL>){
 
if($line =~ m/David/){
$line =~ s/David/Josh/;
}
print $line;
}
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